what is the biggest lift stock 5.3 heads will handle, not the springs but the actual heads them self.

 

If you installed a set of Patriot gold dual springs or something similar you could run .600" lift without problems. The retainer to seal clearance is over .700" so you've got plenty of room. With that kind of lift your next worry is the rocker arm...........

Richard

 

WHat will stock rocker arms stand up to?

 

Well i was looking at around .581 lift. at the high end just wasnt sure if they had to get machined to fit that lift.

 

You'll be fine with that amount of lift. No special machining will need to be done.

Good luck,

Richard

 

Yeah they aren't like the 96-98 Vortec heads were the retainer comes so close to the valve seal, I know guys running mid .600's on lift with no machining required.