These blocks both have 4.06 bore and same crank. What is the difference other than the cam size?

 

LS3 has the lighter valves and I'm sure there is some different casting numbers on a few things but other than that they are the same. Compression might be different but I will have to check.

 

Yeah, the L92 valve reliefs bring the CR down from 10.7 to 10.5

 

Intakes are different, no?

 

yea...92 uses truck intake and LS3 uses the other

 

LSX-L92 cylinder head
• L92 style rectangle port design
• 2.165" solid stem intake, and 1.590" solid stem exhaust valves
• 15° valve angle
• 260cc “as-cast” intake ports, 80cc “as-cast” exhaust ports
• 70cc “as-cast” combustion chambers
• Uses LS3 rocker arms/LS7 bolts

LSX-LS3 cylinder head
• L92 style rectangle port design
• 2.165" hollow stem intake and 1.590" solid stem exhaust valves
• 15° valve angle
• 260cc “as-cast” intake ports, 80cc “as-cast” exhaust ports
• 70cc “as-cast” combustion chambers
• Uses LS3 rocker arms/LS7 bolts

Same block
Same pushrods and rockers
Different water pump and harmonic balancer
Different front timing cover

 

Preshate that! Thats what I was looking for

 

l92 comes with valve reliefs which lets you run a bigger cam.