I am postinng this one for a friend of mine with some Q's

- I am not up to speed on the GenIII internals yet so I figured I would ask the experts. LOL
He has a '01 silverado obviously running the stock 5.3. He has a chance to get ahold of some new LS2 heads for cheap from a guy he knows doing a head swap on a crate motor. He wants to know if they will bolt up and use the same pushrods etc and will his compression ratio go up since he is planning out a f/i setup. If you guys have any suggestions or knowledge please let me know and I'll be happy to relay the info on to him. Thanks guys....

 

They are the same as LS6 heads, just without the light weight valves. They have a 65cc chamber, versus 61cc stock. This will drop CR, which is good for FI. Might run into valve shrouding with the 2.00 intake valve and the 3.78 bore.

 

You'd need to check the chamber diameter too as the 6L's larger bore could be a problem running the heads on a smaller bore 5.3. The chamber overhanging the edge of the bore would be a *BAD* thing!