I've got an 1985 trans am with a 383 stroker, holley 4777-2 4150 series double pumper carb, hooker long tubes, flowmaster cat back system, 3.23 posi rear on 15 in tires. I just bought the car and have yet to go through it all the way so i dont know if it has a performance camshaft. but what should I expect to run in a 1/4?

 

Without knowing how much it weighs or how much power it produces, you can guess anywhere between 13 and 15. Ballpark number might be in the mid 13's. If you can't get traction, 14's or 15's.

 

Thanks for your info. I would still like to know what others would know about this type of engine combo. Your camaro looks sick.

 

No one would know more than Stephen, because you didn't provide enough details to make an assessment.

 

What else do you need to know steven and I will try and give you all the info I can. I would really like to know what to expect from this car so I know what to aim for over the winter. Thanks for all the help.

 

if we don't know stall speed, cam specs, heads, etc we can't make an accurate assumption, but anywhere from 13s to 15s would be my guess unless the combo is dialed in really well.

 

It's easier if we do it the other way around. Go find a weigh scale. Make sure the car is set up exactly the way you're going to be going down the track. Fuel in tank, spare tire left at home etc. Drive the car onto the scale and weigh it with you in it. That's your race weight. That's how much weight the engine needs to move down the track.

Now, take it to the track and make some runs. If you're going to do any tuning, tune to increase your mph. MPH is the indication of HP. ET depends too much on traction. Spinning off the line will give a terrible ET but will affect mph only slightly.

Once you have your best MPH from the track and how much your race weight is, I'll tell you how much HP you're getting to the wheels. After knowing the HP and race weight, I can tell you how quick you "should" be running if traction is perfect. Very rarely will ET HP be more than MPH HP. Even my own car produces less ET HP than MPH HP. Because of torque converter slip, ET HP will always be less.

That will be a lot better than trying to guess how much power a car makes since no two cars are the same.

 

Thanks for all the help. I cant make it to the closest track because they're setting up for the IHRA national finals or something so the track is closed to the public for a while. I have one other question..Is that double pumper carb a good carb to run or should I switch to a diffrent one?

 

double pumper is fine although for a 383 i would be running a 750cfm double pumper, swapping out that rear end for bigger gears, more stall, and then try to put together a more balanced combo.

 

Well thats what was free so I'm all set with that. I do mainly city driving so wouldnt the 650 cfm be fine since I would want more low end power?

 

650 or 750 DP carb would work just fine, the 750 will probably make a little more power than the 650 at high rpm's. Sounds like your combination is pretty mild so it probably wouldn't make much difference between the two carbs. Now if you are planning on a cam swap, gears ect in the future, a 750-850 would be better.

 

I do plan to do a cam change over the winter, but its only going to be a mild cam. I'm thinking about a Lunati voodoo cam with 207*/213* at .050 with .437/.454 lift. Then maybe a upgraded torque converter, not sure on what kind yet either tci or b&m. I basically want a similar setup to yours jbenge. Thanks for all the help guys, I really appreciate it.

 

that cam is so small i think the factory cams are bigger...? Definately call comp cams, crane cams, and lunati and ask them for their suggestions on cams. That thing would run out of breath at 4500rpm probably in a 383.

 

I agree with xpndbl3, if you are going to change the cam change it to something better than that otherwise it won't be worth the effort. I would call Comp and Crane to see what they recommend. You could easily go with something around 225-230 dur. @.05 and and not lose any drivability.

 

How about this cam:

Grind Number:HR-276-2S-12 IGOperating Range:2000-5500 RPMDuration Advertised:276° Intake / 284° ExhaustDuration @ .050'' Lift:214° Intake / 222° ExhaustValve Lift w/1.5 Rockers:.488'' Intake / .509'' ExhaustLobe Separation Angle:112°Max Lift Angle:107° ATDC Intake / 117° BTDC ExhaustOpen/Close @.050'' Cam Lift:Intake - 0° BTDC (opens) / 34° ABDC (closes)
Exhaust - 48° BBDC (opens) / (6°) BTDC (closes)

 

still too small look for 230-ish on the duration at .050, which would still be on the smaller side in a 383. That came is only 214 at .050, needs more duration

 

Ok I think I found some that I like

Option 1:
Operating Range:1800-6000 RPMDuration Advertised:274° Intake / 286° ExhaustDuration @ .050'' Lift:230° Intake / 236° ExhaustValve Lift w/1.5 Rockers:.490'' Intake / .490'' ExhaustLobe Separation Angle:110°

Option

 

For some reason my computer glitched and I couldnt put it all into 1 post.

my other option is:

Operating Range:2300-6500 RPMDuration Advertised:284° Intake / 296° ExhaustDuration @ .050'' Lift:240° Intake / 246° ExhaustValve Lift w/1.5 Rockers:.507'' Intake / .510'' ExhaustLobe Separation Angle:110°

Keep in mind I still want it to be a good driver for during the summer since I live in the city and go to cruisin nights.

 

Well i found out that i have a edelbrock preformer rpm intake manifold, 3.73 gears with an eaton posi, not sure the brand but they are 195cc heads with 64cc combustion chambers, b&m transpack, and an underdrive pulley.

 

The crane cam is a little small even as a daily driver in a 383.I love that cam in a 350 though.Unless you want a near stock idle.Try the next step up in crane 222 230 dur 509 528 lift.This is the came they use in the zz383 gm crate motor and it is very streetable makes 415hp with a dual plane intake and 425 with a single plane. The 112 lobe seperation helps with the idle. If you want a lopeing cam go with the 224 230 502 510 comp cam with a 110 lobe seperation. I know alot of guys will say that a 222-224 dur. is to small for a 383 but If you want a cam that has 15inch plus on vaccum these are the cams for you but you will probably only have 12-13 inches of vaccaum on a cam like this 230 236 510 520 in your 383. The 224 230 comp cam is supposed to make 12-13inches on vaccum in a 350 so it will probably be a little tammer in a 383.