Originally Posted by Ceeker
LS1,3 is pretty much bolt in now days. kits are available and 400bhp all day long.
... and 60 lbs more total extra weight with a T56 transmission. Thats pretty impressive considering you're getting an aluminum V8 plus one of the strongest transmissions evar. The BorgWarner T56 was a tank in my Camaro. (LT1).
An LS1 engine with 5.3L truck heads, LSx intake, 90mm TB, mid length headers and no cats will give you over 460 RWHP. 426 ci can be made resleeving those motors and IF you could manage long tubes you could get 550RWHP and the same in torque out of that engine.
I had a buddy who punished a 426 resleeved LS1 for about 5 years solid in a C5 and it never let him down. Unfortunately he sold it to a guy who killed himself in it on the 427 splitting the C5 in half. I drove that car, it was insane.