Well tonight was my 1st trip to ATCO with the new set up. For thos of you that forget my combo is as follows
1970 Nova..3200 lbs with driver
90/10s shocks and 50/50 rears
400sbc .060 over
350 crank 3.48 stroke
14.5:1 TRW forged pistons
Weiand TEAM G Intake
Comp Cams Solid lift 288 advertised, 259 @ .50 ground on a 106. 550/570 lift
Holley 800 DP
150 shot of NOS
Heads are na 1971 aftermarket GM head. I think is a 373 casting. 2.02's ported and polished and intake matched.
suppose to be a 3800 stall...i think its more like 3400
TH-350
4.56 gears...
Micky thompson E/T drags 15/8.5 I think 26 inches tire
1st run 2nd 3rd
R/T .153 -.104 .130
60' 1.895 1.772 1.798
330 5.235 5.095 5.111
1/8 8.066 7.869 7.882
MPH 86.73 88.31 88.29
990 10.477 10.218 10.213
1/4 12.726 12.363 12.370
MPH 102.16 106.68 108.35

Temp was 79, 78, 77
Humidity was 77, 84, 98%

For my 1st time i think i didnt do too bad. Spun realllly bad the 1st time with 14 lbs in slicks. 2nd and 3rd at 12 lbs i spun about 10 ft so my friends said. Theres more there with tuning...hopefull i can get the 11's
What do ya guys think?!?!?!?

Ummmmm....all that and not very good e.t.??? way too much gear and too short tire...and a 150 shot too? something is amiss :confused:

Congrats on the first passes!

Robert is happy for you too, he just has a hard time showing it tongue.gif

There is a ton left in tuning your combo, or you are running on broken parts.

With 14.5:1 compression, iron heads, and a 150 shot I have to ask what kind of fuel is in the tank? Anything less than C-16 and it is likely that detonation was occuruing, even if you couldn't "hear" it. I would expect fractured rings for sure. Time to do a leakdown test. You should also inspect the engine oil for metal content - detonation tends to pound the bearings.

Another avenue to pursue if the engine is healthy is the trans and converter. With what should be a rocking engine all on its own PLUS nitrous, you may easily be overpowering the converter and/or transmission itself. If the torque that SHOULD be there is being followed by a low performance converter, then you most likely have "ballooned" the torque converter. Ballooning is like a hydraulic explosion, it radically increases the internal clearance from stator to turbine, and will devastate the converter's efficiency. TH350's are great transmissions - but all bets are off if it is a stock type build. Your potential power level will make a stock type TH350 slip.

Race on, Thomas

Is that manifold even in your rpm range?Aren't they good for only 6500 rpms?

Originally posted by Bomber '67:

Robert is happy for you too, he just has a hard time showing it LMAO!! Good one :D

Bomber 67 said what I was thinking about the compression ratio and fuel type. I'm hoping your passes were just on the motor . . .

With your compression ratio and small cam I'm a little concerned about detonation here. Even on race fuel.

Well as far as the 150 goes. 150 is what its suppose to be. Theres no way to know it may be a smaller shot. i pulled my plugs and there was no sign of detonation what so ever. everything is brownish to darker.

The Weiand Team G is good to 7200 RPMS

Eric68, Small cam? everyone i talked to said it was rather large for my motor. i'm confused.... :confused:

I think he means it does not have a lot of duration for a 14:1 motor. Also, a 106LSA is not a nitrous cam.

Ed,
These are spray passes?
Look into buying a set of bigger slicks.

Yea, i can't get any more duration due to valve to piston contact...

Bigger slicks are out of the question unless I mini Tub the car.

What can i do to get into the 11's? This is my one goal...Just to get that 11.99 on the slip.

I havent checked my cam lash since break in, like 5 months now...I'm sure this would help if it was loose. im going to try to lighten it up as best i can and maybe even try another track next time because people say its hard to hook at ATCO.

Maybe a smaller carb? 750 DP...less air makes a snappier car?

more stall?

What was your engine temp when you made these passes,you should try to go into the box at 140° or so?
If you have power steering remove the belt its worth a tenth.

Looking at your mph it looks like your not running it out of the lights.
What did you shift at and where did you hit the spray at?
With those small tires,4.56's and spray your rpms must be pretty high in the lights?

graemlins/thumbsup.gif Bomber :D I didnt catch the part about first time to the track and went right into diagnostic mode ;) now comes the fun part,,,,working out the bugs and going faster :eek:

Okay, here's how you get from "here" to "there".

First off you need to eliminate any "I think" from what you have. I.E., either your tires are 26" tall or they are something else. Guesses on anything will not help you in your quest for quicker e.t.s

Not prepping your car, like a checkup on valve lash, is just like asking for disappointment.

Detonation is not always easy to spot on the plugs, depending on your total tune. Do not fool yourself about iron heads, 14.5:1 compression, AND nitrous. If you find it too much bother to do a leakdown test then re-read the part about guesses and disappointment. And then re-read it again.

Since you have not yet said anything to the contrary, I can propbably safely wager that you have a low dollar torque converter without an anti-ballon plate. You would be in good company, there are lots of guys that load their engine for bear and then back it up with a converter from Wal-Mart. What you will find from many of the guys who run really well is that the converter was a very important part of getting the power to the ground. $150 or $200 torque converters will not get the job done at the track, but cheapies are just fine for the cruiser crowd.

Along with converter/transmission questions you need to asses the rpm efficiency of what you have. Easy to do: compare theoretical "no slip" rpms against actual rpms through the lights. Math is: (mph X gear ratio X 336) all divided by tire diameter. So at 108.45 = 6,385 rpm, 106.68 = 6,286 rpm, 102.16 = 6,020 rpm. Now then what was your indicated rpms through the traps? Divide theoretical rpms by indicated rpms to calculate rpm efficiency. Most good converter/transmission would be 92% or greater efficient. If you are down in the 80's or lower then you have a converter/transmission issue.

Nothing to it, now just get it done.

Doing things like a leak down, or checking converter/trans efficiency are where you need to start if you are serious about reaching your goals - or you can be happy with it like it is. You can always throw some more parts at it and it'll either go, or it'll blow.

That cam may not be ideal for nitrous, but I would not lay that part down as the reason for the car's performance.

Good Luck, Thomas

I think the heads are probably holding you back. But with a 150 shot that should be way into the 11s on an off day. Keep us informed on what you find.

1968 hot rod, My Temp was about 160 after the burn out...At the end of the track it was about 180 190, then on the retuen rd was up to 200. then cooled down from there...stayed around 180 all night pretty much. My power steering belt was removed previously.
I Foot braked the car to about 2500, anymore and i was scared it would push across the line and trip the light, when the last yellow came up, i let off brake, mashed gas, and pressed NOS. I sprayed it right in 1st gear.
I was crossing the line about 7000 rpms

Rapid, haha its cool...i'm a rookie...eveyone laughs at us ;) I think my first trip to the track at 22 years old having a low 12 second car is pretty damn good tho!

Bomber67, I agree with you 100% and i thankl you all for helping me out with my problems with this car. Its really a great experience!!
My Slicks are 26.0/8.5/15. So yes the yare 26's.
My builder was suppose to come buy and help me lash my cam but got into an accident on the way over...so i didnt want to screw it up...so i didnt do it. I'm sure they need it, then again yes...my mistake :(
I will do a leakdown check asap, i'm not doubting you i just read on here that you would see detonation on plugs.
My Converter is a Trans Specialities Converter. Box and part number are suppose to be 3600-3800, flash around 4000. It just doesnt seems like it flashed that hight at all. Non ballooning tho... :(

I know i'm 22...and i dont have aloyt of money right now...but throwing this money into my car kept me going, like something to do besides being out drinking or shooting up. I know i dont have the best of stuff on this car...but my 1st time to the track being a rookie abnd running a 12.3. I'm hoping i can tune my car better, drive it better, and make better selection of parts to get my car into the 11's. My heads are pretty damn stock, just ported. I'm doing all this with the help of you TC'ers...and I thank you all very much!!!
Ed Fletcher

Ed,
Here's why I think that you are doing well: a lot of enthusiasts TALK about how much power they have - you have taken the next step and hung it all out for the whole world to see. Your car will only get faster, meanwhile the cruise night jockeys will still only be YAKKING up the speed that they dream of, while secretly fearing trackside embarrasment.

Let me improve your e.t. without making a single component change on your car: do NOT load it up against the torque converter as you prepare to launch. Seriously, have the engine just above idle, then mash the gas and release the brake as soon as you see the last amber light go down the tree. You will have quicker 60 ft times, which multiply in e.t. savings over the whole quarter mile.

Which run was right at 7,000 rpm accross the traps? If the 108 mph run then 6385/7,000 = 91%+ efficient, not too bad. If it was on the 102 mph pass then 6,020/7,000 = 86% efficient, then you have issues.

Leave those heads on if you are on a budget - compression and N2O make up a lot for lack of flow. Let us know how the leakdown goes. I like to see maybe ~ 3% leakdown, although I would continue running at twice that.

Thomas

Sounds like a good start.
First of all how are you comming up with 14.5 to one. I usually takes pistons custom shaped to the chambers to get that kind of CR.
What cc are the chambers? What part # are the pistons? Dome volume? Head gasket? Zero deck?

Personally I would not be hitting the bottle tell you get it ironed out on the motor. You should be running at least those times or better with no N2O.

Keep us updated.

Originally posted by Bomber '67:


Let me improve your e.t. without making a single component change on your car: do NOT load it up against the torque converter as you prepare to launch. Seriously, have the engine just above idle, then mash the gas and release the brake as soon as you see the last amber light go down the tree. You will have quicker 60 ft times, which multiply in e.t. savings over the whole quarter mile.
I disagree, most of the people i race with bring the engine up on the converter to leave. There are a select few that leave off idle.

Even with the 6 cylinder pulling up on the starting line RPMs typically made for better 60ft's and corresponding ET's, as well as quicker R/T's.

Going up against the converter works great with a transbrake. Doing that while foot braking will load the suspension and hurt 60' times. All the foot brakers I know do not go on the converter. I leave at 1500-1800 rpm. At 2100 my suspension starts to react. I don't want this and you don't either.

one thing about nitrous it doesnt like high rpms i have used the stuff for years in all kinds of different motors and even though your motor will take 7000 rpms doesnt mean to shift it there with nitrous ingaged.......take the car out for a spin try the nitrous say at 35 mph ( wow what a rush) now try it at 70 mph ( not much of kick)put the torque to use is all im saying.....

example: 396 bbc shifted at 7200 rpms in street trim ran 12.20's @ 110 mph on street tires with 1.72 60 ft times.....3.70 gears

with nitrous 150 hp shot with 29.5" MT slicks and open headers..nitrous engaged at start line....first pass 7000 rpm shift points 11.55 @ 118 mph 2nd pass 6500 rpm shift point 11.32@ 120 mph and 3rd pass was at 6000 rpm shift points 11.21 @ 122.9 mph with a crappy 1.62 60 ft time.

nitrous shines in the lower rpm band i would try lowering your rpm shift points and you will see your 11 sec time slip......

with the foot brake comments this is ok if your not engageing nitrous at the start line....but when your running nitrous you need to have the rpms over 2500 rpms before hitting the button........and if your going to do this at the start line it needs to be 2500rpms or higher....just think what kinda serious load the convertor would have to take on and the drive line if you was to hit the nitrous say at 1200 rpms at the line not only maybe the damaged that could be done to the motor........this would be like doing a serious tranny drop......things will start to break.......

preloaded the suspension is a good way to reduce the breaking of parts and ballooning the convertor........im not against the lower rpm leave advice... dont get me wrong but from years of racing with this stuff and doing it on a limited budget i have not used those anti-balloning convertors nore have i ever left the track with broken ujoints or rearends or tranny's......

i have just seen to many people break on the lines at the track and im just one of those person that i would rather preload the suspension to some degree and save my cheap parts for another race.......

just a thought........

I've never use nitrous so my comments may not apply. But I still think traction will suffer if the suspension is used up before launch.

Bomber 67, The last run was the 7000 run, before that was 6800, then 6600 give or take 50rpms.

Gearheads78, The pistons are .060 over TRW part number L2311...377...12.5:1...64.0cc...7.8cc...500 dome
My heads actually checked out at 62cc. My deck was decked to zero and heads were milled. Builder did all the math to get 14.5:1. The head gaskets are a Fel-Pro High compression set. Part number FPP-1004, compressed thickness is .41, 9.2 cc. 4.190 bore

I borrowed my builders TRW/Speed Pro piston book. Maybe someone else can double check for me. It States....
L3211 at .060 over is 13.85:1 with 64cc head. Why is this different than jegs or summit?! Summit is saying 12.5:1 on the same part number... :confused:

By the way, i waa told to shift at 6800 with that cam. I had my light set at 6500...which lead to a 6800 shift. 300RPM marginal right?!

ANyone ever hear of a "Turtle"? My builder says to get it for my intake. It sits inside my weiand, and does something thats gains low end tq. Anyone use or have one?
Thanks again
Ed

All of my fellow racers in my particular crew go onto the converter, and many of them have very impressive 60ft's to say the least.

Ed,
Your comp ratio is 13.18 using a CR program and the numbers you posted,very stout to say the least.
Your 60's are way off for a car with a 150 shot and 377 cubes,next time you run have someone video tape the pass.

With the engine set up you have now you should run those numbers without spray.
Did you run the car past the last set of marker lights at the track,if not that may account for the low mph.

How about this: the next time he is at the track why doesn't he experiment with launch technique. I really want him to try the off idle launch, then hit the spray as the rpms come up as suggested by ddeennis. If the car has any sort of off idle stumble then that should be fixed first, then try the off idle launch.

Motor, not everyone here has an Alf Wiebe stock eliminator rear suspension. In a foot brake launch - no trans brake - the only reason to load up on the rpms is to soak up some of the torque multiplication and soften the initial hit to the tires. If you load up the converter and still get 1.35 60' times then that was exactly what was needed - just not what I think (emphasis on my best guess without any video) is needed here. When a car spins hard off the line, then loading up against the torque converter will lessen the hard spin. To the extent that traction and suspension comply, the greater the spread in a foot brake racers launch rpm and stall, the greater the momentary torque to the wheels. Torque gets heavy cars moving, tire spin slows you down.

Thomas

Well first off, i'm taking the shot of the game here. I was told it was a 150, i dont even know. So i'm just going to not use it next time and see what i come up with.

Bomber67, my friends in the stands said it car didnt Lunge or Launch like the other low 12 cars there. It kinda just glided out of the hole. Like you said I bet i loaded the suspension so the back squatted and the front lifted. Then when i launched, there was no weight transfer because most of it was already there....Hmmmmm

1968 hot rod, yes i ran full throttle untill i passed the thick white line with orange cones. I didnt see lights!?!?

Do you guys really think that i can break 11's with a 1971 Stock Iron head casting? they flow around 165 in stock form. 2.02 valves... and they are still ported but i'm sure they are just cleaned up.

13.18 huh....i'm guessin thats a good thing? lol, so now i'm not as scared about the NOS

Next week i'll go back and try the off idle launch. I'll also have it video taped...

Thanks again Ed

On my Nova (leaf spring rear suspension with slapper bars) leaving off idle (about 800-900 rpm) results in a better launch for me. Loading the converter in my car doesn't allow a hard launch. Can't comment on what works for a coil spring rear setup.

Whooaa, 165 cfm? On the intake? at max lift? That is actually less flow then I would expect even on the exhaust side. 'Dem anchors been holding you back - cylinder head flow is the gateway to power (and acceleration). Gotta go.

Let us know how the off idle launch works for you, post the video if you can.

Thomas

Oh yeah, have some fun no matter the results!