ok ive been doing alot of research on the l92 head. there are alot of variations. they say you can only put them on 6.0 and larger engines. i found a set of l92 heads that have the smaller 2.00 intake valves and said the will fit the 5.7 bore. has anyone used these heads. are they better than ported 243 heads. there only $429 a peice ready to bolt on with .570 lift springs from jegs. the larger l92 heads say 70cc combustion chambers these dont say. this is my plan 5.3 bored to 5.7 and use these heads. does anyone know the max lift before piston to valve clearance with flat tops. here are the specs

These L76/L92 heads can be installed on any 1997-2005 LS Family ov V-8 engines (except 4.8L & 5.3L versions)

Fits any 1997-2007 LS Family engine
2.00" Solid stem intake
1.55" solid stem exhaust valves
.570 max valve lift
Sold individually