I'm planning a 383 build for my '86 camaro but I'd like a little more out of my bone stock LG4 in the meantime. I already have a pair of pocket ported World Products S/R Torquer heads with 2.02/1.6 valves, 67cc combustion chambers, and 170cc intake runners. does anybody know if these will work on the 305 in the meantime? I don't think valve lift will be an issue with the stock cam, but I am worried about shrouding. Let me know what you think.

 

not an expert on this by any means but i think you actually may hurt performance because those are designed for a 350 and your compression would actually drop. i believe the 305 heads are 58cc chambers.

 

Any shrouding will be more of an issue in the combustion chamber than the cylinder walls. And, they'll still flow more than stock 1.84"/1.50" unported heads.

But, as stated, the big issue will be the drop in compression. With a stock cam, performance would probably drop compared to stock heads. Put a different cam in, might be a different story.

 

I wouldn't do it for the afore-mentioned shrouding issues you could have shoving that big intake valve down a small bore motor. Plus you'll have to mill them pretty good to get down from 67cc to the stock 58cc of your original heads to keep from lowering compression.

I'd save them to put on a 4" bore motor later (350/383). Or sell them to help cover the costs of your future 383 build.

Biggest bang-for-the-buck improvements you can make on an LG4 is a good exhaust system (from headers to tailpipe using larger 3" y-pipe, cat and cat-back for a same-year TPI engine) and a mild performance cam (becuase the stock LG4 cam is so horribly, pathetically small). The exhaust you're going to need to do for the 383 anyway so they will swap right over to your bigger motor later on. And an entry-level performance cam like the Summit house brand K-1102 costs peanuts ($90 with lifters). Those 2 changes will make a MUCH bigger difference than swapping heads will.

 

Thanks for the info guys, I'm actually planning on using these heads on the 383, along with a Comp XE268 cam,higher flow exhaust, 2800 rpm stall converter, 750cfm Holley 4150, and an edelbrock intake (performer RPM or Victor Jr.) I was going to put the top end stuff on the 305 while I save for the block and rotating assembly, but I may rethink that now, I didn't realize that there was that large a difference in combustion chamber volume.