Well I finally got to run my 64 with the new Jegs/Canfield 197cc/64cc heads and to my amazment the car did not run any faster than it did with stock 461's on it! It didn't even mile an hour higher, what the @!?* Definately have to get the 60 foot time down but the car just doesn't have any top end. Here's combo - 355 ci, 9.5 comp., 284 energizer cam, 750 vac jetted to 69/71 (good plug read), Perf. RPM, Hooker Super comp 1 5/8, 2.5" pipe with 40 flows dumped at axle. Stock HEI (replacing today) 110 gph holley fuel pump. likes 36 degree timing (locked), shifted anywhere from 5500 to 6000 rpm didn't make much difference. I find it hard to believe that these heads are choking, looking for pointers cause this is frustrating. This is on street tires with SSM's. Here's a couple of timeslips -
RT 60 660 ET MPH Run
.238 2.23 9.28 14.44 95.1 1
.217 2.19 9.26 14.39 95.4 2
.074 2.02 8.91 14.00 96.3 3
.077 2.11 8.98 14.01 96.9 4
.146 2.04 8.87 13.92 97.1 5

Hey Brian (64chevelle) if your still reading this
had a blast running with you last night at WIR your 383 definately has 12's in just a little more tuning!

Help me out here guys, THANKS!
BRAD

I would say it is your cam. That's a pretty mild cam (.480/.480, right?) and the single pattern is good for torque, but you're probably losing a ton of top end. Those heads can probably use a lot more cam in them, and you have the CR to run a bigger one. Someone can recommend a better cam than I, but I'd say step it up to higher duration, higher lift, and you'll see a bigger improvement. Feed those heads!

Thought that I would add that I am running a Torkmaster 3000 convertor through a full manual th350, if that helps.

Bacchus, I agree with the cam thing, I would like to be at that ragged edge of streetable, driveabilty and economy is not a concern. Maybe UDHarold would have a good recommendation, also want to go to a vic jr. intake but funds limit upgrades as fast as I would like. Any more ideas?

With 64cc heads, a .040" quench, and flat top 6cc pistons the SCR is about 10.2. The 284 cam is slightly large for the CR, depending on where it is installed. The cam card is a bit confusing. The .004" duration is 284/284 on a 112 LSA. The .004" event timing numbers are for the cam installed at 111º or 1º advanced. The .050" event timing numbers are for the cam installed at 107º or 5º advanced. So installed at 5º advance the DCR is 7.9, which is fine. Installed at 1º advance, the DCR is 7.6, a bit low but still OK. I wouldn't go any larger on cam without upping the CR.

Have you done any jetting or timing changes? Make sure the timing is about 38º total. You may need to re-curve the distributor. Then start upping the jets a couple sizes at a time. I don't know vac sec carbs so others will have to help on adjusting the opening point on the secondaries. The 3.36 gears are not helping smile.gif .

Might want to verify fuel pressure before spending serious money or time on changing more parts. Get a decent gauge, put it where you can see it from the seat, tap it as close as possible to the carb. You'll probably see the pressure dying off on the top end.

Tom

Hey Pat, I'm running 14cc D-dish pistons (KB Hypers.) 0 decked with .039 gasket, I came up with 9.5 SCR and DCR was 8.2 I believe, please correct me if I figured it wrong. As you can see from the run progressions it ran faster each time, rejetted carb to 69/71 plugs looked good, light tan, timing at 34 to 38 and back to 36 ran 13.92 at 36 degrees timing, distributor has no advance curve it is locked at full 36. About the cam, I believe that crane makes this same grind with a 106 LSA instead of 112, would that be better?

THANKS
BRAD

Excuse me for being overly optimistic but I think this combo should run 12's as it is. The cam, although not perfect, is not that bad a piece. Something seems out of whack to me. :confused: How's the psi in each cylinder? I agree on the fuel psi check.

Cylinder compression at last check was 155-160 psi cranking, ok to me. I know this combo is capable of 12's it's been done before. That's why I built this combo, it's proven. Will check fuel pressure when I can rig up a test line.

OK, I get 9.6 SCR but 7.16 with 1º advance (73º) and 7.4 with 5º advance (69º). What is the ICL? The cam needs more compression (10.5-10.7) to reach it's potential. The same size cam on a 108 LSA isn't going to cut it. Even with 6º advance, the DCR is 7.8 much better but still low for what you want.

For the 9.6 CR you have, the ideal cam is a 268 cam on a 106 LSA, installed at 100º. That yields an 8.25 DCR. This cam matches up better with the 3.36 gears but the 3000 convertor is probably too much. The intake ports are probably a bit big for this cam, too.

Anyway, that's my thoughts. The CR is just too low.

Thanks for the Correct figures Pat, the ICL is 111, exhaust 113, Crane recommends min. 9.5:1 compression and max 11:1 this is the same cam shaft we have run in several of our 9.5 small blocks, same combo as mine, and have gone as fast as mid 12's. That's why I'm looking at all possible problems just finished a cold cranking comp test and all cylinders were 140 psi. Leaning towards fuel restrictions (stock lines) and weak ignition (MSD 6AL on the way) this engine has lots of potential just need to work the bugs out I guess, but hey, that's what hot rodding is all about, a constant learning process! And this site and all you fellow racers are a big help! graemlins/beers.gif

BRAD

That's not much cranking compression in my book.

I would like to see 180+
So I agree with Pat.
One step down on the cam to somethiong with a 224-226 intake duration.

3.36'S graemlins/sad.gif

Torkmaster 3000 stall :confused:
Never heard of it.
Who makes it?
It is possable that it is an inefficeint design and is slipping way too much in with those 3.36's

The convertor is a budget B&M :rolleyes:
Foot brakes to 2000 rpm on launch

You might try lower octane gas. With the DCR and cranking pressure as low as they are, you should be able to run regular.

Try a quality 10inch converter and a set of 3.73's.
ATI, Continental, Hughes

B&M is junk!

You GOT what you paid for.
The converter is more important than most people think.Slipage will cost ya ET.
Do not save money in this department unless the car is going to go up for sale.

I know cranking pressure really does not have to much to do with compression but for comparison here are some of my numbers. On a bone stock 305 short block, 8.3:1 SCR/ 6.8:1DCR using a 272/282dur cam I was getting 150psi. When I switched to a XE256 DCR went up to 7.2:1DCR and pressure to 180psi. This motor has over 100000 miles on it and does not burn oil.

Your numbers seem low when compared to mine.

Steve

Listen to PAT!!

I've been saying it all along that a 9.5 to 1 Motor runs best with about a 268 to 272/274 family of hy- cam!!!

WE can run our old-headed, (read - cast-iron, double-hump), motors good on good pump gas up to just below 10 to 1 CR. AND that is just about the best CR. there is for this sized cam.....

Using the new Vortec's and the alumimun jobbers can up it some to 10.5 or so...

I remember the first Crane, Isky and CC cats I looked at years ago AND they used to be really good about telling us that such and such cam HAD to have this or that CR!! Period.. Now it seems like they list a RANGE so that we will all be suckered into using a schosh too big a cam for the CR. we have to use b/c of the lack of octane in our gas now!! AND lo- and behold it just doesn't run quite right so back to the Speed Shop for another cam!!! (Gee, what are you going to do with that used cam now, throw it away b/c you can't hardly give it away???)...

Think about this for a bit b/c there are many many times I have heard and read that to pick a cam, go for the smaller of the two....

UNLESS you are making a 100 percent maxxed out RACE motor and want every last bit of power your motor can give you..

pdq67

While I can't really add to what Pat has said since I agree he is right on the money.

Your 60 ft times, ET and MPH are all compatible...A 2.0 60 ft 350 +/- sbc will usually ET in the 13.9x to 14.1 range and the 96 mph is in line with with 13.90's to 14.1's as well.

I strongly agree with what Thrasher said on the the converter. Converter is critical. (I did have good luck with a BM holeshot 2400 though)

You should send your MSD 6AL back and use the money MUCH more wisely on a better converter.

MSD 6AL, 7AL3, Stock HEI, points or a Top Fuel Magneto will run exactly the same with your current performance with nothing else changed.

I am presenting this to be constructive.

Where you spinning the tires at all on the 2.0 60 ft runs ?

Yeah, maybe I need to try a smaller camshaft, but my goal is high 12's is this possible with the 272 cam and better convertor with this combo? Or is it time to build another combo? I've spent a lot of time and money in this combo, lined honed, indexed ground and balanced.

There is plenty of tire spin in the 60 ft, I had to load the convertor up at 2000 rpm at the launch to hook. What size of convertor should I go with 2400 - 2800? I'm limited to tire size obviously with a 64 Malibu SS, so tire spin is going to happen unless I run slicks again. (or learn too drive graemlins/clonk.gif )

I appreciate all of the input. :cool:

Well it sort of works like this.
You need to be up in the rpm range where the cam really starts gettin it on.
Below that and your combo will be a stone in the 60ft.If you don't have a good 60 you will never get a good ET.

The closer to peak torque that you launch at, the lower your ET, providing it hooks.
This will mean slicks.Not really an option.

In Hydraulics,
a 350 with a cam that has a 224 duration at .050 will start to really let loose at about 3000.

The 230 duration will start at roughly 3500.

A 350 with a HYD cam that has an intake duration of 224 at .050 peak torque should be right around 3200+ rpm.I think a 228-232 should put it around 3800+.

That means that the best launch will happen with a converter that has a stall speed of 3500-4000.

It has been proven that door cars give the best ET's when the converters flash speed is about 500 rpm higher than the peak torque point.

A good 10inch with a 3200-3500 flash will work well with a 3.73 gear on the street.

If your goal is to keep the 3.36 gears then you should consider something like a 10inch that is built to the tight side, like 2800-3000,
This is to increase the effiency and reduce slippage putting more power to the wheels.
This will work better than a 11inch that stalls at 2800-3000.

The thing to remember is that you don't want to mismatch the gear, tire size, and the converters spall speed.

If you were to put a 3.36 gear with a 10inch that stalls at 3500 you would be working the converter harder/on it more than it would like.
This creates heat, wich destroys trannies and such.

Not sure of your weight but my old 3400pound(with me) set up made it to the 13 flat door with a slipping th-350 and 3.42's.It had a TCI 11inch that had a 2400 stall speed.

The cam was a Crane 278 Energizer
278 221 467 110
This cam CLEARLY needed more converter for it to get a good 60ft.
That cam is an outdated desing that lost me some power.Probably would have been quicker with a cam like the Comp XE228.
I don't think my 1 3/4 headers were helping the 60's either.

When looking at converters it is important to remember that if it is rater at 2600-2800, it is probably going to stall to the low sied.The higher rpm rating is usually going to happen with big blocks, not a small block.

ok, so I should replace the converter (it's had a hard life trust me, it's been in two different cars and I used it because it was available. :rolleyes: ) My car weighs about 3400 w/me. A tight 3000 should probably do the trick, Would a continental be a good choice I have access to these but what would be a good price? Am I going to have to loose the 284/228@.050 crane? It is an old design also. At this point I don't know which way to go, my eyes are crossed! graemlins/clonk.gif I want to do the right thing with the least amount of trial and error.

"Proven combo" only works if everything is identical. All engine specs, weight, suspension, transmission, etc. Its like "BSE". Several people have built something simular, but most never get close to the 10.3-10.4s Ed's pulling.

So unless your combo is the exact same as the guy that ran 12s, i wouldnt think to much of it. Just keep changing things to make it run what u want with the combo you got.

It would be interesting to see your 1/8 mile mph numbers. Most every car in that performance range should gain 20-22 mph from the 1/8 to the finish.
This would give a clue about fuel pressure.
Replace the fuel filter recently?
Running big enough fuel line? 3/8 would be fine.
I managed to run mid tens with a holley blue pump.

Another thing, are you sure the secondaries on the carb are working correctly? What spring do you have in there? Is the secondary diaphragm good? You could be only running on the primaries.

Does the gas pedal in fact allow full throttle? This has fooled more than one racer.

In my opinion, your cam is fine. Choosing a slightly smaller one isn't going to add 8mph and reduce ET by 1 second.

I don't know about all this DCR stuff, but moving the compression ratio up even 1 point from where you are isn't going to get you there either.

3.36 gears will not mph much if any different than 3.73. ET, yes, MPH....nope!

Now, your converter could be bad. But if it's costing you mph....you will need to observe the RPM at the finish line and compare to calculated MPH vs RPM to see if it's slipping a ton.
BTW.....My B&M 10" race converter has survived about 8 years and 3 different cars. My old B&M 10 holeshot is in it's 3rd car ans was freshened up once.
I don't know anything about the low dollar ones they make now.

Keep looking for something obvious. You will find it!
Good luck.

Ron

At 5500 your motor doesn't need any more flow than the 461s give. Use more cam and push the engine higher in the RPM range and you will see the gains that the bigger heads will give you.

"Would a continental be a good choice...?"

Yes, they make excellent converters. They don't advertise much so you don't hear much about them.

I see alot of numbers being thrown about, but what sticks in my head is the 140 lbs cranking compression. That's what a stock 350 does, and no way you'll make great power with so little cylinder pressure, and I do extrapolate that to 5500 rpm.

With 9.5:1 you should be running a cam in the 265-270 range as PDQ mentions. Mike Newby runs 262-268 range in his sbc, which ET's quite well.

If'n you aren't in the mood for a cam change, run more timing( try 42-44 total) and crap gas. A better coverter will, of course help, regardlless.

A friend of mine has a 77 Pontiac Ventura (Nova look alike) Has a 355,flat tops,and Jegster/Canfield aluminum heads (195 CC's I believe)
Cam is a Summit 232/488 114 LSA,Performer RPM intake,700 DP Holley,TH400,10" B&M holeshot,12 bolt w/4.10's..car weighs 3540 w/driver..runs 13.70's with a 1.84 60 ft. at about 96 MPH and change.
Just an FYI,something to compare.His MPH didn't pick up anything either when he went to the new heads..and he had 882's previously if I remember correctly.

When I went from 76cc stock heads (w/.041" gaskets) to pocket ported 64cc Sportsman II heads (w/.018" gaskets) I picked up 5 mph and .3 second. CR went from 8.18 (.086" quench) to 9.66 (.064" quench). The big RPM cam liked that!!

So why is this motor such a tire frying, no traction TQ monster, (340 at wheels on chassis dyno), if this 9.5:1 combo doesn't work? All I'm lacking is top end, so is the cam shaft out of breath? I used to run cams too big and it was just the opposite, sluggish then pick up hard in the middle and top end. Your conclusions keep drawing towards the cam being too big, but I have to disagree with that UNTIL I have eliminated all of the more obvious things first. This motor has a noticeable idle and still pulls 14 in. of vac.! This cam is not that big, w/ 228@.050 and .480 lift. I see a lot bigger cams than that running around in street cars. I have used this cam in a 9.0 to 1 motor with stock heads before with no problems like this. Guess I'll keep diagnosing all other probabilities until my conclusions point to the cam or heads. I didn't change the the chamber volume it's still 64cc but went from 160 runners to 197 runners, I'm thinking I lost velocity, now I have more flow but not enough to feed it, therefore I did not see a change. Thanks for all of the replys. Don't mean to sound harsh, just frustrated.
smile.gif BRAD

Originally posted by KS64SS:
Thanks for all of the replys. Don't mean to sound harsh, just frustrated.
smile.gif BRAD I don't think you sound harsh at all, in fact, I completely understand your frustration. I would be frustrated too if I spent the money and put in all the effort it takes to change heads then to go to the track with great expectations but receive the exact same result.

posted by KS64SS:So why is this motor such a tire frying, no traction TQ monster, (340 at wheels on chassis dyno), if this 9.5:1 combo doesn't work? All I'm lacking is top end, so is the cam shaft out of breath? I used to run cams too big and it was just the opposite, sluggish then pick up hard in the middle and top end. Your conclusions keep drawing towards the cam being too big, but I have to disagree with that UNTIL I have eliminated all of the more obvious things first. This motor has a noticeable idle and still pulls 14 in. of vac.! This cam is not that big, w/ 228@.050 and .480 lift.You make a great case here. I was going to ask how well it runs. Let us know what you find as you check all the obvious things. I miss the days of seeing a combo "turn around" here on Team Chevelle as we followed the progress from start to finish through questions and answers from the other members.

Rod

Originally posted by KS64SS:
(340 at wheels on chassis dyno)I was also curious whether you had chassis dynoed it or planned to but I see you have. The flywheel translation should be in the low 400's which is very decent and should produce low 13's or high 12's. If that's correct then like I said before, somethings not adding up. :confused:

Rod

tunning tips i would say use 87 octane, rejet carb, was that 69/71 for front and rear jets (for some people like myself i put a metering block in the secondarys of the vacuum secondary carbs like the 3310-2 holleys) jetting should be 72/76 front and rear......seems to be alittle lean......at 69/71 , secondary spring has power there as well example back to back runs at the track going from a standard plain spring to a tall yellow spring gained me 1.3 mph and reduced my e.t. just over .10 , a good flowing filter the bigger the better and filter better then just a wal-mart brand..........

more compression would sure help alot....

looks like you have enough for some great top end horsepower numbers wondering if the carb or fuel system isnt in tune yet.........

just some thoughts....

I guess I'm the only one here also suggesting a bigger cam. I don't have the knowledge these guys have and can't throw out the numbers they all do, but it seems to me like you just can't flow enough at the top end. I would say go with something like an Edelbrock RPM pattern cam.

Try out all the other things first, I guess, but I'm still putting money on a cam swap.

I think those heads are the canifields and they also have about a 66CC-67CC chamber which is not helping the DCR. At least the ones I have seen have had 66-67's although some are 65. Never seen a 64 though....

With 340HP at the rear wheels, something is not right. You should be running low 12's as it is.

I ran 11.60@116 (1.60 - 60')in a 3600 lb car with 365 RWHP. This was with a 10.31:1 383 SBC. It did make a pile of TQ though. I also ran a 4000 stall ATI converter, 4.56 gears, and 28" tall slicks.

Something to consider. If you are not hooking up and not able to apply the power you will possibly lose MPH as well as ET. If I spun badly with my old combo it would lose up to .4ET/4 MPH.

Gearing can also greatly affect performance. When my car was a daily driver with a similar combo to yours except it had a old Holley single plane, mildly ported aluminum L98 heads, 222/222 @.050, .447/.447, 114 LSA cam (327/350 cam), stock conveter, and 2.73 gears (one legger), 27" tall street radials. First time to the track it ran 15.88@88 MPH. With only changing to 3.55 gears, the car ran a traction limited 14.60@ 96 MPH. No other changes. DA was about 3000' worse as well.

For optimal track performance I would do the following:

1.) More gear (dependant on tire size used). You should gear the car to cross the stripe near peak HP RPM. Should be around 4.10 gears with a 26" tire.

2.) Quality 3500+ stall converter.

3.) Slicks or some other quality tire that will allow the car to dead hook off the line under full power. It doesn't matter how much power/TQ you make if you can't hook it you will never see the ET.

As another example. A friend of mine had a 10.70@127 car on slicks. He put street radials on for giggles and ran 14.0@111 spinning tires all the way down the track. You get the point.

I think I must have misinformed somehow, when I posted the chassis dyno number I was referring to the peak TQ - 340 at 3000 rpm. Sorry, the horse power is more in line at 300. still enough to get a 13.00 in the 1/4, that's about 385 hp at the flywheel w/20% loss. I found the cam card for the 284, and it's max rpm is 5800 rpm. So maybe I have to high of expectations with this setup, I would be happy with consistant 13's at this point with this combo. I barely got the car home sunday the ignition (stock HEI) finally crapped, barely accells under load when its hot. Will post runs from next sunday's TO's if I get the MSD installed. The new Pro Sim Dragstrip Dyno shows a 13.50 at 102 on street tires, very realistic with this motor I believe. Although I think some of the numbers can be overly optomistic. Stay Tuned!!

Later,
BRAD

K64SS...if driveability and economy arent a concern then lets throw more gear, compression, ALOT more cam and alot more converter at it, and a mechenical secondary carb while your at it, id recommend a demon if you dont mind tuning. Just a thought. Those heads are canfields with a big Jegs stamped on the side if im not mistaken so i highly doubt theyre hurting you at all. I also see your not running a slick or "street slick" Im thinking that would help tremendously, i know im a little late here but figured id throw my 2 cents in. Also what made you decide to go with dished pistons over flattops???

Hey nickel333, the game plan when the motor was being built was to make it as streetable as possible because of a recent layoff, so money was a major factor. The short block originally had 13:1 domes in it and would not work with small chamber heads, it also already had $500 or so of machine work done on it, so we opted for a piston of the same weight and still at zero deck, but closer to 9.5:1 with iron heads. Now I changed the combo to alum heads and will have to deal with it, I should have left it alone, but you how the Horsepower bug works!

A couple of observations...

1) I did a cranking compression test on my car two weeks ago, a 355 with basic flattop double-butterfly valve relief pistons, 68cc heads, and a Comp XS262 cam. I got 170-175 pounds in all 8 cylinders. It's possible you have a problem here...poor ring seal, cam too big, cam phased incorrectly?

2) In my experience, vacuum secondary carbs are real sensitive to the secondary diagphram spring and secondary float level. When I first started out with an XE262 cam and some crappy stock heads, I went 15.00 at 91mph with a Holley #3310 vacuum secondary carb. I got down as low as 14.40 at over 94mph JUST BY RAISING THE FLOAT LEVEL ON THE SECONDARY SIDE. I later went to Dart Iron Eagle 180 heads and swapped the carb for a 650 double pumper, and I've run as quick as 13.54 at 99mph with the same small cam. This is at 3850 pounds race weight, 2000 stall, and 3.42 gears.

You are already at 13.90's and 97mph. I think that with careful carb tuning (accelerator pump cams and squirters, float levels, and secondary spring), careful ignition timing work, and better 60ft times, you can get down around 13.50 at 99mph or so. To go faster, you will probably have to figure out why your cranking compression is low.