How much lift can I run with stock L98 heads without machining the valve spring seats?
I know I will have to upgrade the springs and install threaded rocker arm studs.

I'm looking hard at a Lingenfelter cam (74211) with .530 and .560 lift with 1:1.6 rockers, but not sure if I can run that one without a lot machine work.

 

I just got an email today from Scoggin Dickey advertising stock diameter springs capable of handling .600 lift. I would check the spring pressure requirements of the cam and make sure they are up to the task. You may need a larger diameter spring.

Lonnie

 

i always use screw in studs for anything around .475. the springs for your cam will most likely be larger than stock diameter so you'll need to enlarge the spring seat. cost me around 2 dollars a seat here to get it done. i'd run a larger spring for that much lift rather than a stock diameter spring reguardless of what the spring maker or the parts pusher says.