Originally Posted by vettenuts
Not sure why you need new exhaust valves. The stock rocker on the LS1 is 1.7:1 and I assume the 1.6 ratio you are referring to is for a SBC. On the LS6 heads, if they have the lightweight valves don't replace them.
Oh sorry Not the rockers, I meant the exhaust valve size itself stock they are 1.55" and I was wondering how much different putting a 1.60" exhaust valve in makes