From tbi to Carb and 305 to 355 power & time est.
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Car: 84 Z28
Engine: 383
Transmission: T-56
Axle/Gears: 342 Posi
From tbi to Carb and 305 to 355 power & time est.
I just recently changed my stock TBI 305 to a 350 Carbed engine. The track has not opened yet and I dont see my self getting it dynoed. Just wonder what I may run and how much horsepower may I have?
ENGINE: Chevy SB 355, 600cfm Holley, Edelebrock Air Gap intake, Vortec heads, compression of Pistons with heads 10:2:1, Comp Extreme Energy cam .487/.490 lift 274/286 adv.duration. Hedman Elite cermaic coated headers.
TRANS: 350 Turbo, shift kit, 2200 style converter, mega shifter, and other nic nacs.
GEAR: 342 with posi
Any replys would be great.
ENGINE: Chevy SB 355, 600cfm Holley, Edelebrock Air Gap intake, Vortec heads, compression of Pistons with heads 10:2:1, Comp Extreme Energy cam .487/.490 lift 274/286 adv.duration. Hedman Elite cermaic coated headers.
TRANS: 350 Turbo, shift kit, 2200 style converter, mega shifter, and other nic nacs.
GEAR: 342 with posi
Any replys would be great.
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Car: 87 Pontiac Firebird Formula
Engine: 355 SBC-Thats all I can say or they will break my legs.
Transmission: 5 Speed
Make sure you put a regulator on that carburetor set to 7psi, or you are going to flood out your carb. TBI fuel pressure is around 14psi, that is way too much for a holley
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Car: 84 Z28
Engine: 383
Transmission: T-56
Axle/Gears: 342 Posi
Thanks Formula2fast. I have a reg on it, its set at 5&1/2 PSI.Thanks for the reply man. It would be nice if any people with the same are close to my set up could tell me what they run r how much horse power they have.
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Car: 87 Pontiac Firebird Formula
Engine: 355 SBC-Thats all I can say or they will break my legs.
Transmission: 5 Speed
My guess is lower 13's with that setup. I assume you are probly making about 275-300 at the rears and with that gear, you should get down there in the low thirteens.
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Car: 89 Camaro RS
Engine: 350 carbed now
Transmission: World Class T5
Axle/Gears: Peg Leg w/ 3.73's
Ive seen a few people with almost that exact combo run high 12's so there isnt any reason you shouldnt other than your carb is a little small. There are a ton of super chevy articles with the vortec heads, XE274 cam, and air gap intake making over 400hp on a 350. So thats where I would say you should be as well.
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Car: 84 Z28
Engine: 383
Transmission: T-56
Axle/Gears: 342 Posi
IROCaholic do u like the 670 street avenger carb? I was looking at changen mine for a bigger one. Thats one that I was lookin at. Its either that r a Demon 700. I'm not wanting anything bigger than that. I think a double humper is to big for my setup.
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Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
If you believe recent "revelations" about the SA carbs, a "670" SA flows about the same as a "normal" 600 CFM universal carb.
Do yourself a favor and get a DP, if you're getting another carb, anyway. With 2200 stall, a 355 can easily handle a 750 CFM DP ( http://www.holley.com/HiOctn/TechSer...nfo/P225A.html ). It wouldn't have any "bog" problems with an 850 DP, for that matter (just wouldn't need that much flow).
Do yourself a favor and get a DP, if you're getting another carb, anyway. With 2200 stall, a 355 can easily handle a 750 CFM DP ( http://www.holley.com/HiOctn/TechSer...nfo/P225A.html ). It wouldn't have any "bog" problems with an 850 DP, for that matter (just wouldn't need that much flow).
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Car: 87 Pontiac Firebird Formula
Engine: 355 SBC-Thats all I can say or they will break my legs.
Transmission: 5 Speed
Originally posted by five7kid
If you believe recent "revelations" about the SA carbs, a "670" SA flows about the same as a "normal" 600 CFM universal carb.
Do yourself a favor and get a DP, if you're getting another carb, anyway. With 2200 stall, a 355 can easily handle a 750 CFM DP ( http://www.holley.com/HiOctn/TechSer...nfo/P225A.html ). It wouldn't have any "bog" problems with an 850 DP, for that matter (just wouldn't need that much flow).
If you believe recent "revelations" about the SA carbs, a "670" SA flows about the same as a "normal" 600 CFM universal carb.
Do yourself a favor and get a DP, if you're getting another carb, anyway. With 2200 stall, a 355 can easily handle a 750 CFM DP ( http://www.holley.com/HiOctn/TechSer...nfo/P225A.html ). It wouldn't have any "bog" problems with an 850 DP, for that matter (just wouldn't need that much flow).
Last edited by formula2fast; 03-29-2005 at 08:51 PM.
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Car: 84 Z28
Engine: 383
Transmission: T-56
Axle/Gears: 342 Posi
I see what ur sayn about the air flow. The thing is, is it going to gain me any power going from 600 to a 750 dumple pumper are just more gas being drunk. I've been told with my setup i could run real low 13's r high 12's. How much could I gain from the swap in time r power?
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Car: 87 Pontiac Firebird Formula
Engine: 355 SBC-Thats all I can say or they will break my legs.
Transmission: 5 Speed
If you go too big, you will drop a bit of power and definitly lose some mph down the track. gas mileage will also be affected. It has more to do with air speed velocity into your engine than gas. If you have a bigger hole (venturi) but not the vacuum/airflow in the engine to take advantage of that extra air, you will be loading up your cylinders with more than it needs. It is better to have the smaller hole and accelerate the air faster.
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Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
Gas mileage is typically better with a smaller carb. Not always, depending upon state of tune, but typically.
The flow formulas give you a good idea what is needed for peak power. However, as experience tells us over and over, a larger carb (within the limits of the posted link) will usually give you a lower ET in the quarter mile. It has to do with the way the carb works as you're going up the torque curve.
The flow formulas give you a good idea what is needed for peak power. However, as experience tells us over and over, a larger carb (within the limits of the posted link) will usually give you a lower ET in the quarter mile. It has to do with the way the carb works as you're going up the torque curve.
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