I am looking for more bottom end out of my combo. I am currently using '92 TBI truck heads on the motor now, is it possible to use the heads off the original 305 TPI that I tore out of my car when I got it? Better performance over the TBI's or not? How much CR raise if I am already running 9.5:1? Please give me your opinions. I realize the TBI's are 1.94's and the TPI's are 1.84, so let me know what you think I need some well informed help to squeeze some more performance out of this car. Thanks!

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'87 Camaro Iroc-Z
'92 350 .040-over
Mild Cam
700R-4 w/shiftkit only.
Edelbrock Perf. manifold and Holley 750w/vac. sec.
GM HEI upgraded with Accel parts
TBI truck Heads
Badass 3" true dual exhaust.

 

The heads you're using (193's?) were designed with low to mid range in mind.

You sure about the CR you're currently running? I have a set of 193's too, but always thought they were 72 or 76cc heads because of how much the plug boss protrudes into the combustion chamber.
Maybe I need to CC them one of these days.

You will increase the CR with the 58cc heads, no doubt, but you may not be better off with the lack of flow they have.

If you're working on a tight budget, then look for a good used set of L98 heads or a good set of used aftermarket heads.

There are guys who have run the 305 heads, and after working them over get good results, might be worth a shot?

 

My father is a die repairmen so he works with Cast Iron dies all day and could probably use the grinders at work to port the hell out of them for free. Would they be a step up over what I have or would I be going in the opposite direction? Would they fit with the Performer intake I am currently using?

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'87 Camaro Iroc-Z
'92 350 .040-over
Mild Cam
700R-4 w/shiftkit only.
Edelbrock Perf. manifold and Holley 750w/vac. sec.
GM HEI upgraded with Accel parts
TBI truck Heads
Badass 3" true dual exhaust.

 

It'd be tough to tell, see, the 193's were not built with high performance in mind, and the 305 heads you have were made to make the 305 perform better.

Personally I think it may be an exercise in futility, but changing heads on a carb'ed car is only losing a Saturday, well, maybe Sunday too, if you decide to switch back

Yes, the intake should be a direct bolt up, as long as the 305 heads were from an '87.