Can 1.8 rockers be installed on a stock (intake and exhaust only) 99 LS1 without changing the springs? It is an auto that shifts at 6200. I was looking at the LS7 or simular rockers as a minor performance upgrade instead of changing the cam.

 

the LS7 rocker won't work.
https://ls1tech.com/forums/showthrea...&highlight=pic

 

I'm wondering if shimming the stands, a lot, would bring them into line?

 

Yes they can but it is best to upgrade the springs as well. For that HI of rpm you are pushing, I would most defiantly go with the better springs, retainers and locks.

 

when i put on rockers, i put on ls6 springs.

 

That's what I was afraid of; This is my brothers car, and he is really only interested in "bolt ons" He will never do H/C. I had read a couple of post where guys were trying the exhaust rocker from the LS7 with some luck. I don't really understand why chevy won't make a 1.75 rocker for their "performance parts group"

 

Look around, someone might still have a set of SLP 1.85's
Same design as stock but higher ratio.