Ok, here's the deal.....Im in the process of putting an LS1/T56 setup in my 91 Z28. However, until I get room in the garage and time to do it, I need some heads for my 91 L98. I changed plugs in it yesterday only to find out the valve seals are shot totally now. I saw some 305 heads on the classified and was wondering if they would work? Im not looking to put a bunch of money into the L98, but would like to put something decent on it for now. Could anybody suggest some good heads I could get for around $100-200??? Thanks in advance

 

I think 305 heads will work on an L98. However L98 heads will not work on a 305. I am 99% sure on this, but you may want to get another opinion.

 

Didn't you post this already ?

The heads are fully interchangeable, but L98 heads on a 305 will kill your compression due to the bigger Chambers.

64 vs 58 cc.

 

305 heads WILL work on a 350, they will most likely raise the compression a bit.

My friend has a 12 second 350 w/ stock ported 305 heads.

I have a set of 305 heads that I was going to practice porting on, if ya want them I'll sell them to you. however they are not centerbolts . Send me a PM.

Make sure if you get stock heads they are not swirl port heads that go on TBI's, you want heads w/o the swirl port.

 

Well, I got the heads put on and they really woke the engine up. I also went ahead and put some bigger rockers on(1.6). It really seemed to help the motor breathe a lot better. I also put some SLP runners on and really PORTED the plenum. Im going to to dyno shop monday cause Im curious how much HP I might have gained......Just thought Id let you all know.....I also got my donor 2000 LS1 t/a today