Hey guys,

I recently blew the motor in my TA, and now I started ripping into it. The previous owner told me it was a 350 with '69 Chevelle 350 Heads on it. However when I pulled the valve covers and ran the casting number (333882) it came out as a "70-76 400cid emission heads". Now these are 76cc heads.

I am planning on rebuilding the 350and looking for at least 350HP/350lb ft, do you guys think tha these heads with the proper cam will be able to make a surpass this figure?

P.S. My pistons are 40 over forged dished pistons (no money to get replacments so they are staying) so the compressions with them and the 76cc heads will be about 7.7, or 7.8.

Thanks,
-Max

 

Do not build a motor with that low of compression.

 

those heads are junk and as you pointed out, with dished pistons you have next to no compression. compression that low will prevent you from making any real power.

 

Those smoggers heads have no flow and coupled with the no compression, you're for sure to have a very low performance 350.

 

These heads are basicly good for anchoring your dock.
In your case because you have dished pstons the easy cheap
way to get the performance your looking for is to start with a 58cc head.
This means a 305 head. 305 heads have full sized ports small chambers and small valves. They respond real well to porting and bigger valves.
If you home port them and install larger 1.94 intake valves
you'll meet or exeed your hp goals for not too much money.
The common 305 heads to begin a budget high performance buildup, start with are casting #'s 416,601,450,
081 (centerbolt, Late 305 TPI).
Search my past posts for info on doing this.

Once you've done this a high rise dual plane intake and a hydraulic cam with about 218 to 230 *@.050" duration and .440" to .500" lift will get you the power
your looking for.