350 heads on a 305?

[jonsonton]

Has anyone done this?

I have a set of '87 350 TPI IROC heads and I want to put them on my '87 z28 with a 305/4BBL. I want to know if I can expect a power increase and if it is practical to swap them?

[whoisdabomb86]

i believe when u change the 350 heads to a 305 on top of a 350 bore, ull get high compression and the motor wont last as long, so maybe if u do the oppisite, ull get lower compression and not hurt anything, that could be a good idea if u wanna supercharge. but im not totally sure if im right on this one, anyone else know if that correct

[89IROC&RS]

youd be better off getting a pair of World Products SR torquers. the 350 heads will lower your compression and youll loose power.

[Morley]

Originally Posted by jonsonton

Has anyone done this?

I have a set of '87 350 TPI IROC heads and I want to put them on my '87 z28 with a 305/4BBL. I want to know if I can expect a power increase and if it is practical to swap them?

You can expect a power decrease, the 305 heads have 58cc chambers, the 350's have 64. You'll end up with less compresion and less power as a result.