SS101

iTrader: (2)

so whats the difference between PRC stage 1 and stage 2.5 cylinder heads, besides the valves??? the ls6 heads, not the 5.3's.

if you do know the difference, which do you think would be the best for FI??

5.3LJimmy

iTrader: (10)

The main differences are the valves and springs. The stage 1 heads come with stock valves and springs with the option of a spring upgrade. You would have to contact TSP to verify but I believe at one time the stage 1 heads did not have a CNC'ed combustion chamber either. Personally I would go for the stage 2.5's with the larger stainless valves and the dual springs. It's worth the extra money.

GMCtrk

iTrader: (23)

are stage 1 ls6 heads supposed to have a cnc'd combustion chamber?

I got their 6.0 heads, same cnc program as the ls6 ones, but the chamber is stock?

Sales2@Texas-speed

iTrader: (5)

The Stage 2.5's have the larger valves, and a VERY slightly larger runner volume as well (we're talking 1-2cc here.) The chambers on the LS6 as well as 6.0L heads are untouched to keep the chamber sizes down and keep your compression up where it needs to be for a cleaner/better burn!

SS101

iTrader: (2)

thanx guys, sounds like the 2.5 is the way to go

MARKSZ71

iTrader: (3)

2.5 is the way to go