Before I get any "asleep at the light" or "my gerbil can run 60ft quicker," remarks these were just MPH runs, with no tire heating, no water box, 1/2 tank gas, car exactly as it drives on the street no mods whatsoever, except I was wearing a helmet :D
Car weight is 4020 with 1/3 tank of gas so probably like umm 4060 with a 1/2 tank (including me). Met a nice TC guy at the track, I'm tired now and his name has wiped off my brain, but I tried to track "Lenny" down but couldn't find him to ask a question to.
I am a little dissapointed but I won't get into that now until I verify if there is a line pressure or transmission/aux trans slip issue.
I will post 2 of three runs. I forgot to try a run with the vac advance disconnected, but I can do that another day.
.901
2.369
5.668
8.308
93.03
10.590
12.520
116.62

Run 2

1.003
2.554
5.881
8.528
92.80
10.814
12.423
116.61

R/T is usually not pathetic but I find on street nights at NED they don't give you enough time to settle in once both staging lights are on.

So here is the kicker:
I have a TH400, 1:1 3rd, 3.90 rear gears, except the I was bouncing off the 6500rpm rev limiter for the last 1/4-1/5 (I really wish I knew how far for sure, a playback tach would rule at this point) of the track.
So something behind the engine is not working correctly.
OTOH using the 225(flywheelhp/wt)^(1/3) gives me 116.529 which is pretty darn close to 116.61.
OTOH, there is *no* reason why I should be getting near 6500 at the end. I should be doing like 112-113 @ 6000 and 122 @ 6500.

Whadya alll think?

matt

If your trans is slipping you should be able to smell burnt fluid just after one run, check your trans fluid. I would suspect a converter problem. My wifes camaro runs 121MPH at 6300 RPM but has 3.73's.

Lee

i think when you get the car to 60' youll be mid 11's atleast. with that mph. also by inproving your 60' times you mph should get alittle better then that.

I know there are 11's written all over it in pink magic marker, but thats not what I am trying to figure out here.
Is there any other way to check for drivetrain slip % other than a chassis dyno? Thats accurate as a chassis dyno...?
With a 4000-4100lb car that made 564hp on a water brake engine dyno through its air filter, with 37* timing, my alternator and water pump, my 2" headers, my 3" exhaust with a 3" x-pipe, 20" case mufflers and tailpipes that showed a zero-hp difference between any small, loud performance muffler of different makes.
So somewhere from behind the crankshaft something is missing.
I can check overall slip % on a chassis dyno.
From there I am unsure where to go.
And on the toasted trans smelling the fuild thing, I was driving around for 1/3 of last summer with my 2nd and 3rd gears smoked and never smelt anything.
Don't get me wrong 116.6mph is great, but it bites to work your butt off to be able to try to "buy some speed" and have it never work out.

Too bad the MPH beat Harolds old UDHR4 by 3mph, no valve adjustments and for whatever reason that cam and I just got along well. From a 9.6:1 to a 10.14:1 jump a "similar" grind from another gigantic cam manufacturer company lost 10hp and 25 ft-lbs.

You'd think its easy but I don't know how you guys drive all across the country for a few runs at the strip, its a 2hr drive for me each way, plus loading up the trailer, gassing up the car and trailer, strapping the car down, getting it on and off.. ladada I'm beat.
If I could drive 55mph on the highway and not get beeped at AND I-495 did not look like the Korean demilitarized zone I'd drive up.

Matt

Matt,

Congrats on the times and finally getting the car to the track ;) As for checking the slip... I use a playback tach to verify my converter slippage. Not the cheapest tool, but very accurate assuming you know the gearing and can accurately account for tire growth. With a playback tach you can plot the RPMs relative to the ET. Then you can work the RPM/MPH info out to determine the actual ammount of converter slippage. I will say that your front and back half MPH look pretty proportionate to one another. You're pulling 23-24 mph on the second half ot eh track which is pretty darn good. I'd say you should be happy for your first outing. With a good bite you can run 11.50's and then some more with track tuning.

MadMarv, We had a similar situation with my son's Chevelle which had a 482" BB at the time. He had an enexpensive converter in it that had a little over 3000 stall speed but seemed to slip a lot on the big end. The car ran about 116 MPH @ 6400 RPM thru the lights. We changed the converter to one with a higher stall speed and the car picked up to the 120 MPH range but ran about the same 6400 RPM. Next came an even better converter and we found some more power and the car picked up some more but the MPH stayed relatively unchanged 124 @ 6500. I'd say your problem is Torque Converter related.

Matt,
Just for grins, either pull the chip for one pass or put a 7000 RPM chip in.
I have found on the dyno that running a chip just over what I want to run kills the pull with some chips.
I normally give it a minimum of a 500 RPM cushion so this doesn't happen.
It is not all chips but some are off & it's a pain to get to 8700 with a 9000 chip & have the engine go nuts graemlins/sad.gif
Just went through this again a couple of weeks ago & this isn't the way I prefer to test chips :D

Mike,

This is the softest hitting rev limiter I've ever noticed. Its just a regular MSD but it just kinda stops the engine 100rpm below the chip.
On a second note, if I were to yank the chip (which I was about to do when some guy was like "man your nuts," even though it shifted perfect 1-2,2-3 twice before. The third run I broke traction mid track and did an on-then-off so it wasn't worth posting that slip.
But if I pull the chip, and were to go to the track again, (or get a higher chip whatever, I have a long-rod forged 454 its good for 7k I expect, even with the kinda soft valvesprings) would I just get the same MPH and go to a higher RPM?
Because the way my mind is seeing this is that some sort of slip is "eating" power and it wouldn't make a difference.
Plus my HP peak was at 5700/5800 RPM I see no point in ramming it to 6.8k just because it can?
Or would I *know for sure* that if I ran it with no RPM chip and let it go all the way to 6.8kish rpm where I figure it would at the end of the track that my car has no more power left if the MPH is the same?
Or would it be better to try to see if I have slip/converter issues via a chassis dyno? I almost sprung for the playback tach and I wish I had did, it would be nice to make sure all my shifts and stuff are happening when and where I want them to be.
The guy who put the cam in said it would pull like a freight train until 7.5-8k but I would actually be better off staying in its true power band which is 2800-6200, or from a torque converters perspective, 4400-6300rpm.
A 3-run chassis dyno run here is $75 which isn't bad at all, I could check total slip percent from there.
Think I should do it?
Yeah Ken there is def 11.50's power here, which NED happens to be an IHRA track but I prefer LVD but thats an 11.99 roll bar track.
My goal is 11.99 or under in street trim and I think if I work some kinks out.. I dunno.
I can run 1.8's on my dinky 26" ET streets which should toss me down to the well-mid 11's.
I want to find out if there is a slip issue worth investigating and if there is, fix it.
Ken if you don't mind whats your slip at the end of the track?


Matt

Matt,

My converter (8" ATI) slips 8%-9%, usually closer to 8%. I think that you'll find that pretty common amongst race type converters. 7k should be no problem for your engine. I've spun mine to 7,400 on the dyno (just to see what the power curve would do).

I'd really hate to have to change converters again, its a pain in the arse and this time I think I'd just darn pay someone else to do it.
When they thought metal had come from inside my converter I and I sent it back, I specifically asked what what sort of slip I would expect from his unit and he said "5% or less."
My mumbo-jumbo not perfecto math says I'm slipping at like 9 or 10% now, which isn't unheard at all but if you factor that missing 4-5% in, there is my 119 or 120 MPH run, which is what I had been striving for all along.
The car runs sweet as a song and is a pleasure to drive, I miss the true dual rumble that would shake the sunglasses off a state trooper from a 1/2 mile away, but with it toned down and this rev happy solid cam that seems milder than my hyd roller (except for 1200-1400 park idle, 1000-900 drive idle), if I could crank that 120mph I'd be satisfied. Thats my goal.
Now if someone could tell me why my rubber bumper pad melted off in the sun as I assumed the prepped surface and correct adhesive should last longer than 8 years, why the speckle pain in my trunk is peeling right near the wheelweels, and why a rust bubble is coming through my door just about 7 years after completetion of the ouside paint job..
Maybe its a good thing I have to miss NH super chevy this year..
I need to develop some sort of timer that that lets me use the computer for a certain amount of time for fun if I do other productive things on or off the computer for a certain amount of time.. typing quick and a rambling brain don't mix.

Thanks everyone!

Matt

Matt,
I think 9 or 10% with your weight is probably pretty damn good as converters go but I ain't a converter guy.
Never had or drove anything without a clutch in it for about 35 years except once.
The only car with a converter I ever drove was a friends 48 Anglia a few years ago & it took me about three runs to figure out what to do with that stupid button :D
Every time the lights flashed my left foot wanted to jump up in the air graemlins/clonk.gif
Told the guy that owned the car to put a clutch peddle in with the button under the peddle so I could feel at home ;)

Anyway,,, What I was getting at is the chip could be killing you at say 62-6300 instead of 6500

Matt, I too wished that I could have run the number right out of the box - but that's not the way it usually works.

I didn't see your tire size/diameter listed, from your math it would apparently be ~ 26" in diameter. Am I right?

With those 60' times your 120 mph goal becomes very difficult. Think about it: if on the early part of the track you were ~ .500 of a second slow, how would that translate in e.t. and mph?

Matt, My son runs a 8" ATI expensive converter and it slips 700 RPM at the finish line. It goes 7200 with 4.10 gears and 29.5 M/T Drag Slicks @ 140 MPH. Oddly enough it slipped more when the car had less power.

Hi Matt, it was nice to finally meet you and be able to tell you in person to forget all these dyno numbers and just bring it up and race it! Just kidding- you have one sharp looking chevelle there, and it was running pretty good out the top end. Not as well as you probably hoped, but respectable none the less. I have a solution to your slippage problems, but if you think changing a converter is a PITA, you probably won't like my idea- add the third pedal option! Seriously though, if you ever need any help with anything when you're up visiting the track, let me know. I have one fully equipped shop 2 miles from the track, another under construction, and enough spare parts on hand to build you a whole new car if necessary... Later- Bill

Any car that cuts crappy mid 2.5 60 fts and runs low 12's/at almost 117 MPH is pretty cool in my book graemlins/thumbsup.gif If you could get those 60 fts down the 2.10-2.20 on streets tires you'll be knocking on a 12.00/11.99

...I would say hell with it and bolt on some DOT slicks and go for a real 60 ft.

MadMarv,

Nice dyno numbers. can you post your engine combo? I'm finishing a 462 and I'm hoping for your kind of HP/TQ numbers and was wondering about your cam/heads/compression.... thanks.

I'm with Chris, Matt. Don't even fret about it until you get some real tires on there, heat them up and stab it!

117 is fine. Making the same level of power my 440 is, which I think is damn good for a street car. Don't fret, with slicks you'll smoke me!

Solid cams ROCK!, huh!? smile.gif

If I didn't drive my car so much ( well, I used to but things are really busy right now), I would have went SR as well.

Something tells me you have more MPH in that thing, but since you did the dyno test, assume they tweaked jetting to get A/F ratios right and all that.

Nevertheless, its a cage car bud, >11.99. And if 454Vette says it's a sweet ride( and I trust his opinion), caging it will ruin it's value ( and asthetics imho).

BTW, 454, did you 'row' the Goat up there, How's it running!? I LOVE stick cars! ESPECIALLY with tripower and nitrous! graemlins/thumbsup.gif

I mean, how cool is that?

Originally posted by MadMarv:
I will post 2 of three runs. I forgot to try a run with the vac advance disconnected, but I can do that another day.
.901
2.369
5.668
8.308
93.03
10.590
12.520
116.62

Run 2

1.003
2.554
5.881
8.528
92.80
10.814
12.423
116.61

R/T is usually not pathetic but I find on street nights at NED they don't give you enough time to settle in once both staging lights are on.

So here is the kicker:
I have a TH400, 1:1 3rd, 3.90 rear gears, except the I was bouncing off the 6500rpm rev limiter for the last 1/4-1/5 (I really wish I knew how far for sure, a playback tach would rule at this point) of the track.
So something behind the engine is not working correctly.
OTOH using the 225(flywheelhp/wt)^(1/3) gives me 116.529 which is pretty darn close to 116.61.
OTOH, there is *no* reason why I should be getting near 6500 at the end. I should be doing like 112-113 @ 6000 and 122 @ 6500.

Whadya alll think?

matt Do you have numbers transposed in these runs? The difference in 1/8 to 1/4 times is unusually high, almost 7 tenths with the same gain in mph. There is even a 3 tenths difference in the last 320', and to go 320' in 1.61 seconds you have to average well over your trap speed.

was it on short radial tires? thats why you're revving high.

It will kill some RPM to use 28" tall Bias Ply tires.

To answer a few questions..

The numbers I posted are exactly as is on the slip, but .01 mph change? Something odd here? I have no clue.
Thrid yeah I was running on 25.6" tall p315/35s that I launched easier on at the track than I do on the street when I do my little backroad practice 0-40's.
I can't/won't cage a matching #LS5 so 11.99 or better is useless until I can do standing, as is, 11.99 or under in street form. I also have been really considering the stick idea, a solid roller 6spd would be a blast, but I couldn't bear with cutting the car up for a stick if its matching #s.
Would be fun though :D
I talked to the guy who installed my cam today and he told me that my slip #'s seem correct, and that he said if I am never going to 60' the car (which I won't because of a cage is to ditch the 3400rpm converter, ditch the 3.90's , stick in a tighter more efficent converter and some 3.42s or something.
That being said, he also said what Bomber said if I am reading this right: If I am not going to 60' a heavy car, I've already shorted myself 10mph or whatever (just an example) because the car is now trying to play catch up to itself for the rest of the track.
He also noted my point that at 6500 or 6800 my motor is making easily 100 or 200 ft-lbs less than it does in its "prime" 4400-62/300 powerband, or even the 2800-6300 powerband, the torque difference is like.. 502 ft-lbs min to 550 ft-lbs max.
So I am gaining absolutely nothing by over-reving the bleep out of it and the car can't really be pulling.
NED is an 11.50 track and although I prefever LVD 11.50 vs 11.99 gives me alot of breathing room :D
Seeing as I tow it anyway atleast until the never-ending 495 project is fixed, I can
1) Buy some 28" MT ET Streets and sell my 26" tall ones and learn to pull a decent 60' out of my converter
2) tone down the gear and converter
or
3) both(?)

The carb was tuned on the engine dyno, not chassis dyno.
Whats has the potential to get me those 120mph traps I have been grabbing for, or is this, to borrow from John ashcroft "operation pipe dreams?"

Matt

you DEFINEYLY need taller tires! :D

As for my engine combo I am part of the rectangle crowd, not a serious drag racer, and not as old (in a good way) or experienced as 4/5's of the people on this board. Judging by the crowd at NED last night there won't be too many guys know these cars like they grew up with them and work on them still in a few years...
That being said: (IMHO for everything)
1) Solids are more fun, tad more powerful.
2) Hydraulics are easier.
3) Rollers always make better power.

If you do a roller, keep the lift under .640-.650 or lower if you actually drive the car. I have talked with an think are decent cam companies, bullit, cammotion and UDLunati, I do run a mega large cam corporation grind but that was not my choice.

If you want a budget build do stock ovals al-la Racer1320 style, if you can dip into the newer, higher end stuff, I say do it.

The rect port combo I would make at this point:

Holley 950HP
performer RPM rect port
AFR 305 or Canfield 310cc rect port heads
4 bolt or splayed 2 bolt block Mark IV block
electrical or carter 172 (if mech need big line)
10:1-10.3:1 static compression forged pistons
forged 4.00 stroke crank
decent, quality forged rods
balanced
1 3/4" coated headers
full roller rockers or ask around about those ball tipped long slots with crane kool nuts? out of my league here.
cam:
all depends on if your gonna do it roller or not.

Like I said-- I'm probably the wrong person to ask.

My combo is the abobe with 10.2:1 a holley 750DPw/ 850 base, and a (too) large solid roller, and (too) large 2" primary headers.
4060lb with me, a helmet and a 1/2 tank of gas. 3.90s (dislike!!) and a 12 bolt.

Err this is a litte off the thread here, but before I even consider buying a 2800 stall or whatever converter, IF I was to go that option, can they even get the slip down to 4 or 5 % ? or is it always going to be 9%?

I had a cheapo 11" converter that was a loaner on my car when I did the chassis dyno, and it slipped at 9% @ 110mph..?

Matt

and a (too) large solid roller, Matt,
Another possibility if you think your cam is too large (you probably don't want to hear this) is take your new cam out and have re-ground. If I remember correctly, your cam is something like 256 / 260, .643 / .643" lift(???) you could take out about 10 degrees of duration and keep the lift the same. I recently had Isky re-grind my cam, it only cost $110.

Should help low / mid range power. You could then (if you wanted) take some converter and gear out.

Matt,I don't think any performance convertor could be that tight % wise (4/5%)

Your ET/MPH with street tires is very impressive,even with a terrible 60 ft.
Its very obvious its a solid 11 second car with the right tire...
So what are you NOT happy with and what do you expect?

Chris,

I called back the torque converter company and talked with a woman on the tech line for about ten minutes.
She told me 9% slip is fine and that it can get as bad as 15 or even in wicked bad cases 20%.
She said whomever I talked to on the phone didn't hear my question right or was flat-out wrong.
I'm not unhappy. Lets just call it a case of "less than you expected itis." I was hoping to trap around 119 or very very low 120.
After some explanation that my car may be hurting its MPH (which I had never heard before) because its playing "catch up" for the rest of the track, then I may be able to do it.
So for right now nothing is going to change. The converter slip is fine, the trans is fine, the rear end is fine, the engine makes decent power for a 462, especially considering the weight of the car (and chevelles in general).
I am just going to have to decide over the summer and with some help from you guys on what if any changes I should make.
Now that I know for sure my converter isn't slipping excessively, is there any reason why switching to a lower-stall converter would help mph? I know I talked to some guy about fin angles and stuff like that that can magically seem to make a car mph faster but nothing in fact has really changed, he was basically saying its not just stall speed its fin angles and whatever and whatever.
I'm just wondering if there is any possibility of gaining MPH through a converter change?
I've gotten my 60's on those p315s down to like a 2.1ish which could put me in the 11's as is, and that would be the frosting on the cake. I'd be happy.
My goal for this car has basically always been (because I can't cage it) sub 12 ET @ 120 in absolute as is street form.
Can I do it? Looking for ideas..

But overall I'm happy. The car cooks, on the street I launch it alot harder since I don't have to wait in line again to try to not blow the car sideways to practice 0-40.
My only problem right now that I want fixed is the transmission kickdown, I floor it and the thing just hits the rev limiter.. nobody so far has had a suggestion about it..

I need to break a finger with a ball peen hammer so I don't type messages that are so long..

matt

BTW, 454, did you 'row' the Goat up there, How's it running!? I LOVE stick cars! ESPECIALLY with tripower and nitrous!

I mean, how cool is that? Not sure if I did the quote thing right, but we'll see. How are you Gene? No, I was just stopping by to see if I could help out some buddies last night. Not racing. The guy who did the site work for my new shop is running a 77 T/A that is just on the very edge of the 10 second zone running 11.0/123MPH.Playing with timing and jetting looking for that oh so elusive 1st 10.99 or quicker. Another friend's 66 GTO is sorting through some problems coming out real strong but nosing over in 3rd gear 12.3(!)/95MPH(!). I just happened to notice Matt's nice chevelle and wanted to compliment him on it. I'm not much for the ghetto wheels on classic muscle, but his car looks good with them, kinda like the Hotwheels cars we used to play with as kids(or some of us still do...), or those newer toy cars with the oversize motors sticking out of the hood rat-fink style. I think he is just a little disappointed with the cars performance not running quite as high a MPH as he had hoped despite making some over-the-winter performance improvements. One thing you guys should note is a lot of you are telling him he needs a better 60 foot(stickier tires,etc..) to get some better ET's- I think his ET's are freaking phenomenal considering I watched his 1st run as he drove AROUND the water box, did NO burnout whatsoever, and just DROVE off the line. I was expecting a 13 flat, and was amazed to see a 12.4/117. Looked real fine playing catch up and stomping the car in the other lane for sure-

The only other thing I am sort of weirded out by is that (and maybe its because the 60's are so high it has no impact) but a change from a 2.554 60' to a 2.369 60' netted a .097 gain in ET.
Maybe that little for every .1th on the 60' you get like 1.25-1.5 on the top end doesn't apply until you are actually pressing the car on the 60'?
But I still would expect a greater difference?
As of now and the near future I am doing nothing to the car until I just kinda think here whats going on. I know you all hate numbers games but I should be able to muster a 118-121 with what I've got but its not adding up.
But the car drives great, the carter 172 did its job just fine.. I think I should sit back with a cup of newman's own lime-aid (if you like lime popsicles, try this stuff out) and put the car into the garage and let it rest for a bit.
454Vette-- Your name dropped from my head because I replaced its space in my limited brain with Lenny's-- but nice meeting you.


matt

bolt on some 28" tall slicks and go pick up your 11 second time slip. good luck mike

454Vette, yeah, you're absolutely right. I'd be happy as hell with such 'easy' ( no smoking/slicks) shakedown runs.

Matt don't change a thing. Save your pennies for some 275/60/15 BFG Drag Radials or equiv, and then you can think about sorting it out.

Dude, on street tires, sometimes ( and tracks are slipperier imho), the old red car will spin the hides midway through a gear, maybe 5500 or so. It **might be** that simple. Stealth spinning almost.

Anyway, I wouldn't dwell on it, nor change ANY parts until you get some track tires.

And you know what I think, a smaller SR like the 502A3 would have given you a bigger smile. But , hey, no way to prove it. That's one of those disconencts between dyno runs and actual performance. Smaller is bigger sometimes. Open the lash up 2-3 thou next time you're out and see if you feel the midrange pull pick up. See if your 'seat of the pants' is correct and track test it. You might want to go the other way to see if better high end power might ET better on street tires.

Guess that's the first changing I'd do. +/- 3 thou each way and see.

And remember one change at a time when you start monkeying with it. Don't monkey too dilligently until you get track tires.

STOP OBSESSING AND GO SMOKE SOME RICE!

So you've got 315/35's that are 25.6 in diameter - that means you have 17" wheels right? With the reduced sidewall distance and no heating of the tires you are doing fantastic. Some taller street tires on 15" wheels would do you good - and sticky drag tires would make you understand why launches can be so much fun smile.gif

Your slip is less than 9%, do the math.

Theoretical no-slip mph = (6,500 x 25.6 x 2.96)/3,900 = 126.29

Now subtract actual mph from theoretical, 126.29 - 116.62 = 9.67

Then divide lost mph by theoretical mph, 9.67/126.29 = .0765, or 7.65% which is on the upper end of efficiency for performance non lock up converter.

Yes, there are converters that get down in the 4-5% range, but for damn sure there is a HUGE pile of performance converters that never make it into single digit efficiency loss.

No two drag passes are likely to be the same, especially with less experience and a learning curve in effect. The guys on the forum that actually see consistency in how the numbers from one part of their run affect the other parts of the run are usually the guys with many passes under their belt. So, for the moment suspend all belief about how reductions in 60' times result in a multiple change of the total 1/4 mile e.t./mph. If you just bring the 60' down to 2 flat you will have yourt magic 11 second pass.

You'll get there, just start making the simple changes that you know you need - like the tires, and everything will all come together.

Thomas

Thanks for the simple and good words bomber.
I have shot off 1.80 60's on 26*10.5R15 ET streets (which is like an 8" tread tire...).
I don't know if its just me but I can def. launch the car harder on the street on my radials than the track, I honestly think the track can get quite a bit more slippery. People seem to disagree with me though.. but my butt-o-meter says I'm taking off alot hard.
Anyone out there using the BFG p315/35DR? I know it has a tiny sidewall too, but in theory I could run that on the street as my normal street tire and hopefully (?) (sidewall too small)? get a 2.0 60'?
I was considering the other end, a new set of welds, 28*12.5R15 ET Streets. Its a shame I have these 15" rims with 5.5" BS that don't clear my brake calipers by like 1.5mm MAX-- I can slide the wheel on and not notice it, but when I put the car in drive its like I left the parking break on. They are the right size and were a steal, but they don't fit. A set of DOT drags like that and I think this engine has the power for 11.2x ET's at 116-118 mph.
The reason I hesitate on the tall by big ET streets is that I want this car to pull off the 11sec pass in as-is form, which maybe if I could justify replacing my p315/35gforce tires with the p315/35DRs. I just wonder if I could actually get an improved 60' out of them vs the gforces with a legal tread depth on the BFG's.
If anyone is wondering, gforce or not, small sidewall radials+drag= slow start. But! Great for highway onramps :D
Yeah I know I goofed on the math, but the 9% was just a head-calculator deal at that point.
I also wonder if I don't go the big DOT drag route if I should de-gear the car, because my torque difference at 6300 vs 6500 is 150ft-lbs.
I suppose I could slip it into overdrive? .78 ratio to keep it in its power band? Anything over 6300 is pointless for the motor, all dyno runs were stopped at 6200 because the torque was starting to fall off very quickly although HP was still there (but not going up, just dropping alot slower).
I should have thought of that while at the track? I'd hit about 4800 mathematical, with some slip like 5000-5200 and I'd be at 545tq-510-520hp vs 559hp @ 6200 but 473tq?
Point being I am doing myself no good going through the traps pushing the motor beyond its useful rpm range, would using another gear help or hurt?
(GV, stab the little thing, if the fluid level is right it shifts pretty quick..)

matt

Matt

Do you have a lockup converter? I found that with my car, locking the converter in third gear was worth about 2 tenths and 3 mph in the quarter, from 11.90's@114 to 11.70's@117.

To post a 10.81 1000' time and a 12.42 finish line time a car would have to average 135 mph for the last 320' of the quarter mile. How fast is your engine turning at 135 mph?

According to (rpm*overall tire height)/(R&P ratio*336)
I get (6900*25.6)/(3.9*336)=134.779
But I wasn't anywhere near 6900 ? How do they do the trap speed averaging?
6900 is whizzing my motor so far out of its useful range...
about the lockup converter.. I have a TH400 w/ gear vendors OD.. had it been easy to get strong 2004R's without being in the know or cheap for what you get computer control and all 4L80E's I would have done that, but that stuff came out just a little while after I did my GV-- and now there is a hole in my floor because of it!
I know you can buy lockup converters for TH400's but they are $$$$ I think. I haven't really checked to be sure but they looked expensive..
I'd love to lock my converter in 3rd..
But where does this 6900 rpm come in?
If I don't bungle the math if I click into 3rd+OD I get .78 which gives me a 3.042 overall gear ratio ? Should drop me back down to around 5k but maybe the bettter option here is to down the gears a little? I have 3.31's still but that seems like a very drastic change from 3.90's for a motor that seems like it adds 4 cylinders at 2800 rpm...
This is all based on the assumption that my tires are 25.6", someone suggested to me that I actually measure them by drawing a line on the tire and on the road then rolling it because a few thou off the diameter could screw with the circumfrence big time..

matt

matt

but my last outing pre-cam swap had basically the same 1000ft?

.664 rt
1.850 60'
5.037 330
7.750 1/8
90.40 mph
10.104 1000
12.095 1/4
113.16 mph

new run:

1.003
2.554
5.881
8.528
92.80
10.814
12.423
116.61

but I cam nowhere near the RPMs I am now at the end of the track-- the cam and incorrectly installed valesprings would have nuked the engine.
I don't ever recall even coming close to 6500 with that motor, 6350 was the highest it ever saw and thats because the darn thing just plain wouldn't rev any higher and 3rd gear was cooked (found out the hard way).
btw, 113.16 to 116.62 is what.. 35hp?
Seems like I went to alot of trouble to be bouncing off the rev limiter at 116 but not even touching it at all before?? what changed here now I'm confused as heck.

matt

To post a 10.10 1000' time and a 12.09 1320' time you will have to average about 108 mph in that 320', quite a bit different than the 135 you would need for the other run posted.

The 12.09 run shows you ran the last 660' in 4.34 seconds, an average speed of 103 mph, which looks believable, given the 113 trap speed.
The 12.42 run has you completing the last 660' in 3.90 seconds, an average of 115 mph. In order to clock 92.8 at the 1/8 and 117 in the 1/4 you must have either exceeded 117 by a large margin or increased your speed almost instantaneously to 115+ at the 1/8.

Matt, the people that I've known with rear disc brakes being too close on their 15" wheels used wheel spacers to solve the problem. Of course it all depends on where the interference is.

There is no secret to the fact that at street car drags the track may be slippier than on a public road. Let's see: many hard street tires tearing off the good track surface traction, street tire cars tracking water up to the line.

Also, pay attention to pressure on low profile tires. When run too low, a low profile tire will cup the center tread section - resulting in a loss of traction. In a heavy car with low profile tires, even the BFG Drag Radials, I have seen more people run quicker with 27 to 30 psi. The natural thing "everyone" does is to (wrongly) lower their low profile tire pressure at the drags.

You'll get there, you have too many of the right things going - now you just need to dial it all in.

Thomas

Matt, The second time slip has to have something wrong in the finish line ET. At every other point on the track you were eight tenths off due to poor traction. I've seen bogus E.T.s caused by something blowing in front of the finish line timers and tripping them prematurely and this is what must have happened on the second run as three more MPH isn't going to change your time very much, a couple of hundredths maybe. Your REAL E.T. must have been more like 12.80.

Nah Harold I think the ET is correct.

I don't think the 2.5 second 60's were doing this motor justice.
I did three runs, and my et for all 3 were 12.423, 12.520, and the run I goofed on 12.652.

all with 60ft from 2.554 to 2.369. The goof run was a shifting mistake and I went from 116.6x to 116.09.

Onovakind, I sent you an email at your address in case you don't check it. You lost me along the way.
I have wheel spacers-- in 2 different sizes too, maybe I can get away with using those15" wheels (cheap, black, steel, but pretty light and just fine for what I'd be doing with them).

All in all for a 4020+ lb car with rectangles and true to street form the car did some arse whipping. I think the absolute max potential for the car is like 11.0x but in reality I could get it down to 11.3 without any other work than bolting real tires on and trying a few different ways to see how and how hard to hit it at the line.
The real question is can I get it to 11.99 in this mode but heating my p315 g-force road race tires or if I need to lay a 700 ft strip and then buy p315 drag radials..
I wish they made the g-force drag radial in the p315/35 size, I don't know what the difference is in performance but the tread design is so much more pleasant than the BFG drag radial.. talk about an ugly tire..

But if you didn't catch it the whole 320/660 ft speed average thing doesn't make any sense to me and I don't understand what message you are trying to convey with it..
best of both worlds here would be to see if I can nail an 11.99 with my regular street tires and then bolt on some slicks to show the true potential, but I have a feeling that even though NED is 11.50 ET for a rollbar/cage whatever I *think* I could go right past an 11.50 after a few trips to the strip.

matt

Speed average means what speed you must average in order to get from A to B in X amount of time. If I want to travel 1 mile in one minute, I have to average 60 mph. If I cover the first half mile at 45 mph, I will have 20 seconds to finish the mile. This means that I will need to average 180 mph for the last half mile in order to get to the end of the mile in one minute.

Look at your time slip, the 12.42 run you posted.
If you pass the 1000' mark at 10.814 seconds into your run, then pass the 1320' mark at 12.423 seconds, you have gone 320' in 1.609 seconds. If you do the math, divide 320 by 1.609 to get 198.881 feet per second. To convert ft/sec to mph, multiply by .68181818. This will produce an answer of 135.6 mph average speed for the last 320' in the quarter. I don't think you can accomplish this.

If you look at the previously posted run, the average speed required to cover the last 320' in 1.93 seconds is 113.05 mph, a much more reasonable task. I am not sure which numbers to believe, but I don't believe your car will run 135+.

I understood about the a to b in x amount of time and speed necessary (hate spelling that word) but my question is really what does what you are saying mean in terms of my car and what it does performance wise. Does it indicate something is wrong, or that there is a piece missing from the equation of my timeslip (like, for example, the timeslip is wrong somehow, which I doubt because both runs where I didn't goof are similar enough to not make me think one is bogus.

I appreciate your time and thought into this-- I find it interesting. And also, according to my math mph = (rpm *tire diameter)/(gear ratio * 336) = 126 with no slip? unless bungled that equation (6500*25.6)/(3.9*336)= 126.something

That run is some sort of anomaly. I did it with my 12.520 run and got 113mph average, which seems ok, and on the run I goofed on 112.407?
Is this average speed an indicator of potential ? or just something to look at.
I still don't see how my 1st run broke the laws of physics.. hehe something must have been screwed up on their equipment that time.
matt

Matt, Get out your calculator for a second and see how many feet per second your car is traveling at your terminal velocity of 116.6 MPH. 116.6 x 5280 / 3600 MPH x feet per mile devided by seconds in an hour. ( 171 feet per second at the speed trap) At the speed of your terminal velocity it would take 1.87 seconds to cover the last 320 feet. My soms car can't make it in the time your slip shows and it's going almost 20 MPH faster than yours at every point from the 1/8 mile on. trap speed is generally 138.5 on his 9.6-9.7 second Chevelle. (9.74-8.12) 1/4 vs. 1000 ft. times.

Harold I don't know as much about racing as you, but I have three time slips from the track, and they all of them except for the one that is obviously wrong (135mph average 320') but its pretty darn unlikely that that the machine recorded my info wrong or incorrectly or some oddity like that, its a timeslip, its there, the other cars I was racing were nowhere near me by the time we were at the finish line...
I did the math... my other two slips showed an average of 113 (1.93 320') and on my goof run 112.4(1.941 320') for the last 320'.. with a trap speed of 116.6, those numbers seem perfectly logical.
If its not possible its not possible, I will be heading to the track again but this time maybe just heat the tires a little and see if I can start to learn to 60' those p315's...
If the slips come out the same again, then thats that..

I mean I suppose I could call new england drag way and ask them if any other racer noticed massive discrepancies in their timeslips or if their "compulink starTrack" was off that night, and I bet they would say no.
There were guys there running pretty quick and pretty serious cars, not as fast as your sons but I think guys who have been racing long enough to notice these sort of things off the bat and say something.
My time slip with a different cam, at a different dragstrip, shows me going the last 320' at LVD doing a 12.09 with a 10.104 1000' is 1.991 seconds.
I don't see the huge issue here, and it doesn't seem like anyone else on the board is picking up on it.
There was obviously a problem with one slip because it is impossible for my car to travel at 135mph without me kicking the gear vendors switch.
Going back to 1998 my first time racing ever, on different wheels, p245 radials with a 2.25 60', 460, UDHR 4 left in drive did the last 320 feet in 2.034 seconds. 12.703-10.669
I don't see the issue here?

Matt

I'm not trying to tune your car or select a converter, I'm just pointing out some obvious discrepancies in the timeslip numbers.

In the first one you are at the 660' marker 8.803 seconds into the run doing 93.03 mph, arriving at the 1320' marker at 12.52 seconds doing 116.62 mph. This requires an average speed of 106.83 mph during this distance, very likely given your 116 mph top speed.

If you look at the second run, the last 660' occurs in 3.892 seconds, requiring an average speed of 115.6 mph, not likely for your 116 mph top speed.

If you're trying to tune your car, you need believable numbers.

Matt, Im only saying that since you were eight tenths behind on the run you spun badly on that your finish line E.T. should also show about an eight tenths loss in E.T. or close to it. You will find that most cars that spin a little generally pick up some MPH at the end of the run, that part is normal. I think that something tripped the E.T. timers besides your car. I've seen this happen many times in my 40 years of drag racing. If any time slip shows obvious discrepancies just discard the results unless the car felt better or all the way down the track and good luck as i think 11s are only a matter of good traction for you.

Harold/Onavakind/anyone who reads my dribble/

Do you think all the timeslips are wrong? Or just the one with the 12.4?
I need some sort of reference point here...
Is my car a 12.5 w/ a 2.36x 60' @ 116.6?
Or should I disregard all the timeslips this time?
The next time I was planning to try to use my ET streets at NED, but I have never been able to get under a 2.0 with them there, but I can easily do it at LVD. Maybe NED gets too watery and I should just dry-heat the ET streets and try a run..
Or should I go back up on my regular tires for another series of reference points?
I know you guys are sick of me moaning at least to some degree, but I am not thrilled with the 116.6. I was hoping and was told that this cam would finally get me that magic 11.99 on street tires at or near 118-120. If I dry-heat the p315 street hides and get more agressive with the throttle, I can def. pull a better 60' I've done it before, but I've also gotten too aggressive blown it sideways and junked a run, so my tendency this time was to go as light as possible on takeoff.
I can't cage a matching # LS5 and I can't afford to buy a race oriented velle yet and I'm not letting this one go. So I figured the way to do it was to power myself there.
I got talked out of a moderate hydraulic roller into this solid roller, and now I have to worry about lifter failure valve lash and overall engine life, for what amounted to 3.5mph with the same trans, converter, tires, etc..
Its a quick car but for all the work I went through this winter to get 3.5mph..
You'd think you would see more of a difference going from a 286 @ .006 230 @ .050 .639 single patten hydraulic roller to a 287/291 @ .020, 256/260 @ .050 .643 solid roller. I would expect to see at least 50 hp..
Yet when he dyno'd my old engine, he called me up and said "what did this thing run in the 1/4? you should be near 120mph" and that was with the 540hp on his dyno (560-570hp on the guy who built its dyno) and when he installed the solid roller he got 565hp, and that was including the x-pipe, but then again there was a 25hp loss from the 1st dyno (engine shop) to 2nd dyno (cam shop) which I guess was just the addition of the accessories and exhaust. Then I get 25hp from a solid roller and an x-pipe..? the problem is these are just numbers and its patentely obvious from my experience alone they vary from dyno to dyno and operator to operator, so the track was to be my dyno and now it looks like I have bunk slips?
Now I tried to placate myself by saying well its going through the air filter, running the alternator and water pump, going through my headers, my mufflers, my tailpipes, and telling myself that had to suck up 40hp and the new cam was really making 605.
I know its a quick car and people are sick of hearing about it, but 454Vette hit the nail on the head when he said I was a little dissapointed with what I got for MPH given the work that was done-- true duals to x pipe, small hyd roller to medium+ solid roller..

I mean.. from carb to oil pan to tailpipe.. even with 4000lbs.. I don't see why I am not hitting 120 or even 118 with this car.

holley750dp w/ 850 baseplate, choke horn milled
edelbrock perf rpm rect port
dart 320cc rectangles, 116.5cc combustion chambers
comp 933 springs (off my head, could be wrong)
lunati titanium retainers
crower SS roller rockers
manley pushrods
4.00 GM forged crank
6.385" eagle rods
10.14:1 CR
isky red zone lifters
comp CR lift rule 287/291 256/260 .643 112LS 104.75ICL
2" hookers
3" x-pipe
20" case turbo muffs (equal HP to other tested muffs)
tailpipes

4020lbs with a 1/3 of a tank.


The real question if anyone actually read this far is whether my MPH will pick up if I can bring my 60' down to 2 flat or even 2.1 on street tires(bad pinion angle)? or is 116 what I go? I was really under the impression you can spin the car pretty darn hard and get the same MPH, so I wonder where mine went? Or should I roll those timeslips up and smoke them? I think if I go back to the track I will do it again on the street radials, but smoke them a little with no water, and do my runs but try one shifting into overdrive instead of buzzing the engine.
I know the car is quick but I didn't hit my goals that I have been going for all along. Times like this I want to roll the car into a rock quarry or put some moth balls in it, a cover on it, and put the thing up on cinder blocks. I know ken runs a nutty converter and canfields, but his flat out amazing 127mph runs say he is making over 100hp more than me with a cam that has almost the same seat timing and mine just has some more at .050 with more lobe sep. I am not saying I expected 127, 125, or 123, but 120. AFAIK don't we have some flat tappet UD288/296's running 11.2's @ 120 on the board?
and I managed to miss the first 15 min of the sopranos so I will have to wait till 11pm tomorrow for it.. anyone have some tranq darts?

matt

Here's a link to a 4075# 470" Pontiac wagon with some example timeslips. There's a timeslip at the bottom of the page, and another one linked under 2001 Performance Update.

http://www.pontiacstreetperformance.com/psp/rebuild455jh00.html

The 11.32@117 timeslip takes 4.17 seconds to complete the last 660', an average of 107 mph.

The 11.77@113 run takes 4.33 seconds to run the last 60', an average of 103 mph.

Note that last 660' average speed is about 10 mph less than the trap speed.

I don't think that your timeslips provide much useful information. Is the 660' time correct? Is the 1000' time correct? Can you believe the other numbers? I certainly don't think that you ran over 135 mph during one run.

Take a good look at the specifications on the Pontiac wagon. How does your setup differ and would you be better off with something closer to the specs of the Pontiac?

Paralysis by analysis. Get some rubber under there and get a few more datapoints before you infer anything.

Oh, and not-for-nothing, but you are probably 200 lbs heavier than any of the other cars you refer to, that in and of itself, is worth what 2 mph?

i read most of the posts and a few years ago i built a street car but my goal was to have a car that ran low 12's in street trim and would mph over 115 mph........i built the car and it worked.........i ran a bbc in it as well......and to launch on street tires which i did i knew i had to kill the low end torque to allow for the traction to happen and let the motor rev up thru the rpms to allow a constient hard pull thru the lights..............

i ran 3.70 gears in a 10 bolt rear end........and i killed the torque of the motor down low with a wild solid cam.......262/273 @ .050 this along with a chassis set up i was able to run consistent 1.70's 60 ft times with a best of 1.72 with your everyday run of the mill BF tires that was 275/60-15...........

to me and my thinking is this.....you have limited yourself on the rpms and you have way to much toque down low to even think about trying to hook on street tires.........if you was to kill the torque down low either via bigger cam or smaller convertor (to allow some lag time before the power comes on to fast to over power the tires) and to gear the car so you can reach your mph goal as you cross the finish line............


even the cam i had in my car was way to big for the streets but it allowed me to hook and i let the rpms carry me to the speeds i was was looking for.........even thou the cam was 4500 to 7500 i only took my bbc to 7000 rpms and thats were i crossed the finish line ...........

so your goal can be done but you have to break the normal trend of building a car for all out everything.......hope some this helps.........

Gene.. Onovakind.. et al.. thanks for you patience with my insane attitude.
Believe it or not, (LOL) I spent the last 45 minutes analyzing the average mph for every foot-distance on the timeslip that timeslip data allowed.

My conclusion is that the runs from NED are likely all invalid, however, by linking the run that I assume to be good (the 12.520) with the run I assume to be bad (the 12.43whatever) and re-calculating it all step by step, the 12.43whatever run with the 2.5x 60' should have been a 12.74, extremely similar to the 12.80 Harold Sutton said it was probably.
My brain-wracking analysis says 28" tall tires should produce a sub 11.99 or better ET with a corresponding slight mph increase.
My alternative is to kick the overdrive switch at 6200 in 3rd gear to prevent buzzing the engine, dropping the engine to somewhere between 4850 and 5200 (no slip-8% slip) and hope it does the same thing at the tall tires.
For continuity's sake, I won't be doing this attempt on my 26" tall ET Streets. I am going to do an actual physical measurement of my street radials when hot from high speed driving to simulate their actual size after a run.
Either way, if the weather is good expect to see me at NED on Friday. I have a 2pm job interview but if the weather is good and I can get out of my suit in time, I'll be there. I'll have the trailer and car ready to go, and pray I can get out of my suit quick enough.

I don't expect very different data, but I need data to work with here. The problem with the 28" tire solution is it violates my 11.99 or quicker on street tires rule. Obviously a pair of DOT slicks would send the car into the 11's, but I am going to try a combination of a dry heat of the p315/35s (I use the same normal air pressure as I do on the road as on the track) and shifting into overdrive to see if a 6200 to probably 5100rpm change is better than buzzing the engine that high. It makes no power at anything beyond 62/300 rpm.

Thoughts?
Should I go about this different?
(aside from tires at the moment)

Hi Matt, I sincerely believe only the run with the terrible loss of traction is flawed. Everything seems to correspond up to the 1000' mark so if you add the average amount of time of the other 116 MPH runs for the last 320' you should have the true time of that run also. The taller tires will cut into the gear a lot and will probably cost you some 3-4 MPH. Do you have a posi-trac and is it working properly? Do a burnout with the street tires and have a friend check the pattern to see if both tires track the same (10-15 feet). You definately have enough power to run 11s but its hard to do on street tires. Some tires work better with more air pressure and some don't. I think BFG Drag radials work well and Mickey Thompson E.T. streets are sticky but are not as good as all out Slicks which can even be had in your present diameter. Any increase in diameter will probably slow the car down and your running pretty good for a tank. P.S. Do the traction testing at a remote site so as to not get busted.

Matt, One final thought, I just saw the post that said you were getting 26" E.T. Streets and they were nearly the same size as your street tires. These should be as good as you'll get as far as the gear remaining the same so disreguard where i posted about the loss of speed as i thought you were going up several inches in diameter rather than just 1/2 inch or so. These tires require some heating up just like slicks. Good luck and keep us informed of your progress.

Thanks Harold and everybody else...

I am going to try to hit the track on wednesday, but I will be there again without a bumper pad.. stupid thing fell off! makes me look like a twit.
I am unsure if I will do ET streets, I might do them and shift into overdrive to see if I can get what I want, that 120mph ticket-- eer slip.
Seeing as my boss's 03 cobra is doing 117 with cat back x pipe and cold air, I don't want to know what he is going to do with more boost. Stupid new cars..
I broke his roto tiller today and I know zero about putting together recoil starters and its driving me nuts..

If I hit the track, I'll be sure to post and tell everyone what happened.
I might skip the water box and just dry heat them, I have big radials up front and don't like to go through the water box with them. Whatever.. The tires are old and I need to expose fresh rubber :D

Matt

why are you going to use Overdrive? Overdrive is for cruising, not for accelerating.

Motor Mart because with a a 25-26" tire I am hitting my 6600 rev limiter for the last bit of the track, a good distance.
My peak HP is at 5800, the engine starts to fall real fast past 6300. I am down so much torque at the 6800 rpm it took me to go through the lights w/o a rev limiter that shifting into overdrive will put me back at 5000.
If I am going to stick with a 26" tire, the best thing to do would be to de-gear it some so I come through the traps at around 6200 with my 8-9% slip converter.
Since the motor is no good at that RPM I can't be doing myself any possible benefits for acceleration. So I if I kick it into the next gear, then I will still be in the power band. I make alot more torque at 5000-5200 which is where a shift from 1.00 to .78 would put me than I do at even 6200, and with it falling at 20 ft-lb chunks per 100 rpm past 5900 torque is probably dead at 6500, never mind the actual 6800 I really needed to hit the traps.
My motor will pull right past 7500, but I am not making power, the power in my motor is done at 6200-6300.
So there is no sense in revving it and going nowhere.. just cus its spinning doesn't mean I am accelerating.. so I think there is a possibility that I could get better acceleration by shifting into a 4th gear instead of bouncing off a 6600 chip (at 6500 rpm) or installing a 6800 or 7000 chip and bounce at 6700-6800 for a microsecond or let it go all the way and have 7000 there for just safety.
I was surprised to see hp peak so early for what I consider to be such a large cam with such a wide lobe separation, but that is how it came out.
Ideally a 28" tire solves this problem, but I run a 26" tall tire on the street and my ultimate goal is 11.99 or quicker in street trim. I might try to ET streets to see if I can 60' at all for *once* at NED (meaning sub 2.00).
I am just going to pass the water box and heat them up until I see a bit of smoke in the mirror and then go to the line. I did that at LVD except I backed into the water box so I would avoid my huge front radial tires going through the water and bringing it back. Since I don't care about these ET streets, getting them hot w/o some water doesn't bother me.

make any sense to you?
matt

Matt, Go ahead and drive around the water then back into spin once to get the water all the way the tires, pull forward and do a normal slicks type burnout as dry spinning won't get the tires up to max traction temp. Should easily go 11s. My sons '71 Chevy truck with 3.73 gears went 11.32 @ 116.9 MPH at 4080 lbs. so i know your car can.

with the tire issue when i was dealing with my street car and running 1.70's 60 ft times with regular 275/60-15 bfg tires it took sometime on our little pad way off the track to see where the tire pressure needs to be.

i first started out with 32 psi as i would run on the street but to come to find out this pressure was to much.......when i did a small burn out you can see when you get out of the car that the whole tread pattern wasnt getting laid down.

so i lowered the pressure til i got an even wear pattern on the cement.........and the tire felt warm all the way across........and when i went to far down i could see the center of the burn out fadding away.........

so i ended up with a final 18 psi that worked the best made a big difference on how the car hooked.........

i myself drove around the water box and backed into the edge of the water and pulled just forward.........i then would run the motor to 6000 rpms in first then shifted into second gear and took it to 6000 rpms and lifted on the brake and stayed into the gas then hit the brake in time to roll into the stage lights...........

this produced the best traction for my set up and i could launch almost full throttle and hook.

with a street car with tires it takes some practice on how to get the feel for when the car is just on edge of breaking loose.........

getting a car to hook on street tires didnt happen over night but months of tunning the suspension and learning how the car can take the power with out blowing the tires.........

at one time i did change my tires to a 29" tall tire it just killed the 60 ft times and my trap speed fell about 3 mph...........so that was not to my likings and i just learned to do it on the smaller street tires.........

I think that Matt's idea of using the extra gear has a lot of merit. Speed is only measured the last 66 feet of track. If he is already on the rev limiter, then he is probably starting to slow down. I am sure all of us have seen a really fast ET with a speed that seemed out of wack. By gettingback into the power band of his engine, he might be able to put some more of hi HP to use. If he is past the torque band, then his HP is probably flattened out or dropping as well. I say give it the OD.

BTW a Bias Ply tire grows with speed, that'll kill more RPM.

Having peak power at 5800rpm doesnt mean you shift at 5800rpm.

I shift at 6200 rpm...

But if you see my dyno charts, 6500 is flat-out useless. HP is down some, but torque is down well over 150 ft-lbs vs. 5000rpm.

If it works, it works. If it doesn't, it doesn't.
Don't think of it was "overdrive' think of it as another gear-- if your motor is falling flat on its face at 6500 (never mind the actual 6800 it took me to go through the traps all the way w/o a rev limiter), why rev the engine to where its making no power, and it can't possibly be accelerating faster than where you may be down 20hp but up 150 ft-lbs.

I am going to give it a try.
And as Harold pointed out, I paid my 17 bucks too so I am gonna ttake my sweet time backing and rolling through then out of the water box, then smoking them into 2nd.
I am going to leave the sway bar on, even though I took it off at LVD.
I don't think its worth the 15 minutes (heh) that it takes when I am still trying to get a baseline tune out of this thing.

Matt

Matt,how about a taller tire? Like a 275/60/15 ?

Chris I'd like to do it but as 454Vette noted I have "ghetto wheels" on the car meaning 17" rims. He said they look tasteful though, and I do too.

I could in theory go back to my 15 wheels except that my brake system won't let a 15" wheel go over it in the front.
And the brakes are the best thinng I've done on that car consdering the # of stupid and unesc. things I've done.

A taller tire would fix RPMs and I could probably get a 2-2.1 60' out of them..

It looks goofy with a 15" wheel on back and 17s up front except when they see the M/T painted over...

Slicks never look stupid. Haven't we taught you anything. Its not all show and no go man, it's GO AND SHOW!

gene (or anyone who enjoys the misery of others.., or enjoyment of the mal) (there is a german word for that, schadenfreude "A malicious satisfaction in the misfortunes of others" check my post in bench racing... what a day...

matt

Nein shaUDENFREUDE! Dare I check it??? I don't want to hear anyone's bad news man. But it wouldn't look silly wirh track tires on and rubber bands in front.

Nah I not about the tires..
I drove to the track today in a wicked hurry after a job interview (set up the car + truck in the morning, ET streets and all, *awesome* weather for track runs), came back, ditched the suit, drove to the track and realized I left my wallet and money at home when changing in a frenzy..
matt....

Schadenfreude, defines my mother-in-law to a T. Well, with a heealty dose of intolerance thrown in. :rolleyes: graemlins/sad.gif

To all you young lovers out there, get to know your future wifes mother, because in 15-20 years your wife will be just like her. This is a common fact from someone who is 60 and wiser now. Former wife is long gone now, Thank God and Greyhound.

Speak of young lovers, the 'velle and I are taking a break until next wed. I haven't touched it since I parked it last wed after my goof.
Next wed I am driving back from the cape after delivering a washer and dryer for my mom down there, then gas up again ($44.10 for 20 gallons tonight..) then I am going to try my luck again.
I broke a 20 year old rototiller this week, finally fixed it, it seems I have the midas touch of a broken mirror and a black cat.

If I am not too tired or not on time enough to hit the track wed, or the weather looks bad, I am heading to the track, dropping the tires to 18psi (ran 16 at LVD- but had more practice with that cam.. none whatsoever with this one.. I do know this cam will overpower these DOT slicks right past 2nd gear in drive at 1/2 throttle stab when they are at 28 psi (drove to gas station to fill car up), old friend who was into cars there asked for a little jab, usually I don't but its a little side street so I goosed 1/2 throttle and the rear end of the car went two different directions I cut back and forth and I saw my shift light go off.. This thing revs so fast its unreal.. I couldn't do that with either of my hydraulics if I tried..
Makes me wonder if I should reinstall my pass side airbag before going to NED.. I had it in @ LVD at like I think a pretty low PSI-- should I stick it back in or leave it out?
When I was at LVD I had a disconnected (but not removed) front sway bar, and rear air bag at like 16? PSI. I should write more stuff down..
The one thing that drives me nuts about my car is that it goes schizo when it spins--- it never spins in a straight line, the rear end always kicks its butt around one way or the other, there have been times where it felt like I have seen the back of my car through the window it was so sideways.. if that thing would spin in a straight line, I'd be alot more confident about trying more agressive launches. The problem is compounded by the fact that it does not always spin to one side-- it picks a side, then I usually overcorrect a tiny bit and it blows to the other side but in a less severe fashion, as I am easing off the gas quickly. I know the airbag thing is supposed to help but I hear all this conflicting info about chassis preload etc etc..
because I can't hold my car at 2500 anymore, I am holding it at 1800 then getting on the gas. With the ET streets I should be better prepared to take advantage of my torque converter, but those 10.5" (ET street measure style, more like 8.8 tread or something) I can break them loose at the 330 mark if I am not careful.
I don't run tubes so won't go under 16 with the pressure, plus I read somewhere with a heavy car (4000-4100lb car) that I should use more PSI for a better takeoff.
And I am going to slow things down at NED.. I hate how they rush me there, I know some may think I"m a nitwit/dork/scared kid but I feel like I am getting run through there like the buffet at foxwoods..
Like harold sutton said, I paid, so I should be able to back through the waterbox, drive out slowly, then do a correct burnout, prestage, take a deep breath, stage, and go.
The other cars at NED don't even have the common courtest of waiting for you to prestage before thye finish totally staging. I'm not sure if if its a rule or not but I thought you were supposed to pre stage, then wait for the other car to pre stage, then you could both stage.
Most of the cars up there are running sub-100 mph passes, like 93-94mph, or I'd say so anyway. Not that my 117 rounded up makes me special, but its a different sensation to knock off 117 than it is 94 mph.. (drove a buds stock mustang 5.0 down the track, did a 14 something @ like 94?) Different ball game.. and the thing was a stick and I usually don't drive sticks, but at 14 seconds it seems like I've been driving a stick my whole life.. I learned to drive on one but dont own one.
Wish I had an old impala convertible with a 6spd and a EFI 502 for a cruiser.. Sitcks are just plain fun but my car is an auto and its stayin that way..

thanks everyone for their support on this group-- I'd have probably put the car up on storage blocks and unregistered it by now if it wasn't for you all..

Matt