if i get a set of 5.3 heads off a 01 truck can i just bolt them on and go. also what will my compression go to. can i run pump gas still 92-93 octane. will these heads help me out alot or a waste of money thanks kenny

 

W/O any work (porting, bigger valves) they're a waste.

Untouched, they'll bring your CR up to about 10.8:1 (that's still ok for 92-93 octane).

They're a good choice for a N/A motor but you have to spend some money on them to make the swap worthwhile.

 

as a direct bolt on the are not worth the time, but ported and polished with bigger valves then yes they are some very nice heads. we do a number of the 5.3L heads for heads and cam setups.