Thread: 302 chevy

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Originally Posted by glennsexton

Hey Craig - welcome to CHR.

If you have genuine 302 parts, you could certainly e-bay them as there are always folks looking for the real thing to do a period correct restoration for a Z-28. I have to agree with the above posts, i.e., the heads are old and the technology has come a long way since 1968. A 383 needs to breathe to be effective and the stock 302 heads will hamper that process.
My 2 cents,
Glenn

I agree. Pro-filer 195's with 72cc chambers, flat-top pistons with compression height of 1.425", ~7 cc's of valve relief and zero block deck with a 0.040" head gasket will yield a 10.0:1 static compression ratio and a 0.040" squish, perfect for pump gas with aluminum heads.
http://www.profilerperformance.com/r.../sbc-23-degree
Use this retrofit roller cam together with genuine Howards retrofit hydraulic roller lifters....
http://www.summitracing.com/parts/hrs-110885-08
and produce an 8.76:1 dynamic compression ratio. The motor will want a genuine 10" converter that stalls at ~2500 rpm's and some numerically-steep rear gears.

Use an Edelbrock Performer RPM 7101 intake manifold (or Holley 300-36 or Weiand 8016 or Professional Products Typhoon 52021). Motor will operate with any carburetor, but will make the most power with a 750. Keep fuel pressure at 5 psi at the carb inlet. More pressure than that can overpower the needle and seat in the bowl and allow the fuel pump to blow raw fuel into the intake manifold. Use 1 5/8" diameter headers with an X or H pipe immediately after the collectors. Headers with flange thicknesses of less than 3/8" can curl up from heat of combustion and spit out the exhaust gaskets, so choose good quality headers if you don't want to be foolin' with them all the time. Use a 14" x 3" or 14" x 4" air filter arrangement so the motor can breathe.

With good quality machine work and careful attention to detail in assembly, this motor should easily produce 425 hp and 450 ft/lbs of torque.

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