How Much Horsepower Can I Expect

toy350 · 11-07-2002, 08:37 PM

I am rebuilding the engine in my midyear and was wondering how much horsepower this combination will make.

I a building a 383 stoker (350 bored .030) using 5.7 in rods with corvette 58cc aluminum heads (1.94/1.50). The compression ratio is expected to be 9.25:1 using Keith Black 28cc dished pistons. My camshaft is a mild roller with a lift of 471/480 and duration @ .050 of 219/227. The lobe separation is 112 degrees. The rocker arm ratio is 1.5:1.

Thanks. Also any suggestions to increase horsepower with the combination without affecting reliability, idle quality or streetability would be greatly appreciated.

vader86 · 11-07-2002, 10:04 PM

how big a carb?

toy350 · 11-07-2002, 10:43 PM

Hey Vader86,

It has a standard TPI from a 1988 IROC Z with slightly larger than stock intake runners.

vader86 · 11-08-2002, 02:06 AM

Ditch the TPI, seriously.

You would be making 420+ if you were using a Superram or something similar. But with a TPI system off a camaro, youll choke it to death, you wont make nearly enough power, and almost none after 4800rpm. You will have a crapload of torque however.

With the TPI, i would say between 350-375hp

69stingray · 11-08-2002, 02:12 PM

Here is a good website for reference:

http://www.geocities.com/MotorCity/7610/dyno.htm

383 w/ Ported Vette heads and LPE cam similar duration, more lift) made close 440 HP.

I would bump the compression a little. The ZZ4 crate engine has those heads and a 10:1 compression. I haven't heard anyone complaining about street manners. the 10:1 should give you some higher numbers.

bcwaller · 11-08-2002, 04:00 PM

I get amazing torque running a Dyno2000 simulation. The run says over 500 TQ at 2000 RPM! HP peak is 345 HP at a measly 4500 RPM. This is damn good for a daily driver, but you likely leave a lot on the table if you want to run it hard.

I can't vouch for the accuracy of the similation either....

69stingray · 11-08-2002, 09:38 PM

Here is a 440 HP / 480 lb ft TQ 383 (via LPE).

383 w/ 5.565 rods
Ported Vette heads with 2.00/1.56 valves
LPE Cam (219/219 Duration @ 0.050 lift, 0.503/0.525 Valve Lift, 112 Lobe Separation)
Superram intake w/ 58mm throttle body
1.75 headers

NOTE: 362 lb.ft of TQ @ 1600 RPM! :D

You may also want to look at Edelbrock's Pro-Flo EFI. It can support 400+HP on a 355. No laptop needed!
http://www.edelbrock.com/automotive/mpfi_sbchevy.html