So, life has gotten in the way of car stuff this year and I need to prioritize. My nitrous built motor for the IROC may have to wait cause the wife's vehicle comes first. I have an lq4 I'm gonna rebuild and plan on eventually putting a turbo on it. My goal will "only" be about 800 flywheel HP since based on a lot of research that motor will hold up without going high dollar. So 3 questions... What pistons, what heads, and what compression ratio? Since I'm gonna tear the motor down can I just do a good set of flat top pistons with the stock heads? Would a set of ls6 heads with flat top pistons be to high cr? Those are cheap when they pop up on Craigslist. Just looking for some experience based input before I start buying stuff.

 

What fuel do you plan on using? 91/93? Race gas? E85? I'd avoid the 243 heads since they have a smaller chamber then the stock 317's that are on lq4 and lq9 engines. I'd shoot for a compression ratio of about 9:1 or so.

 

What is your budget? If it is tuned right you could make the stock bottom end survive (albeit on borrowed time). It won't really matter what aftermarket bottom end you choose as all of the major players will be strong enough. You will spend the most money on supporting mods (oiling, studs/bolts, bearings, machine work etc). The more efficient the heads you choose (meaning non OEM castings) the less boost you will need to make that power.

 

Stock bottom will be fine when prepped right. Right clearance and ring gaps

Else do budget rods and forged pistons stock crank. K1 molnar or compstars be fine