hello first time up here question is im looking to get 500 or so rwhp out of my 2000 ls1 ive got the whole engine torn down and ready to put back together stock pistons and rods with ARP rod bolts but dont know enough about the ls series engine to pick my cam and valve train i want to buy some 243s but am on a budget so the question is what size valve should i run and what cam to go with it to reach 500rwhp or greater looking to go n/a for now but dont want to waist alot of money please help

 

243 heads on a ls1 will not get you to your goal. It's go take a serious set of heads and a good size well spec cam to get you there.
Be realistic here and ask yourself is you able to handle a big cam north of 240 duration in a ls1. Which is a big cam for a small motor.
You'll need a good decent budget for a LS1. Start Here.... https://ls1tech.com/forums/generation-iii-internal-engine/732392-recipe-500-rwhp-heads-cam.html

 

man thank you that is a ton of useful info

 

I was in a similar boat myself. After alot of research, the above link being one of them, I determined that making 500rwhp or close to it on a stock cube LS1 was going to be a max effort build and not cheap by any means. You mentioned a budget and not sure if you already have any supporting mods done such as LT headers, aftermarket intake, ect. Also, not sure of your thoughts on the forced induction route, but a mild h/c/i plus a small shot of nitrous or a turbo setup with mild boost could get you to those numbers. Then again, depending how thorough you get with a forced induction setup, the whole budget deal goes out the window pretty quick.

 

well im not exactly sure where im headed i was thinking vortec supercharged maybe the supercharger itself isnt to expensive if i buy one used but thatcan come later rite now ive got the engine out and apart doing the rings and rod bearing this weekend i hope. i still have the stock intake and heads but want to upgrade b4 i go put the engine back in the car i do have 1 3/4 LT hooker headers and a full 3 inch dynomax exhaust im asuming the guywho had the car b4 me was set up for forced induction the engine had huge injectors and ran rich as hell sported some flames when it was steped on hard then it started in with some lifter tap so i decided to go for broke and rebuild now im not to sure where to go