current set up:
383 sbc
edelbrock e tec 170 heads
rpm air gap
comp cams xe 274h
750 double pumper
heddman headers
4spd

what effect would 1.6 roller rockers have on performance?
how much more lift?
i see some setup with a combo of 1.5 and 1.6?

thanks, adam

easy math on the lift Adam... divide the lift by 1.5 and then multply by 1.6 for the corrected lift. Be sure to check valve train geometry for proper fit with the 1.6's when you make the swap.

do i need to change pushrods?

Your pushrods should be fine. It will basically make your cam a litle larger. If your engine wants more cam then it's a good and easy way to get there. What effects it will have is hard to say, looking at the info you did provide, I would say the engine will probably like the larger cam effect.

Be careful here. XE cams are "Fast Ramp" cam profiles with accelerated closing and opening points. Adding 1.6 ratio rockers to the mix will accelerate the parts even faster. You may have more valvetrain noise and accelerated valvetrain wear. :D