Datzneat

iTrader: (4)

Hi guys. Just wondering what my setup will make on the motor if I swap out the bottom end from the 346 to an iron block 408 and use everything else I have on it now.

Top end:
Ported Fast 92/92
PRC 5.3L Heads Ported Stage 2.5
TSP 1 7/8 Heads to gmmg
MS3 w/113 lsa
U/D pulley

I think that's all that matters equation wise on the top end. Currently it makes 461hp/400tq at 10.5:1 cr. I still need to do the math on the pistons as I want to get the cr down to 9.5:1 (might swap the heads out eventually). Let me know what you guys think the extra cubes will do for me.

bww3588

iTrader: (49)

i *think* the combustion chambers on the 5.3 heads will be too small for the bigger bore (4.030 as opposed to the 3.898 of the LS1). you will end up with a lot of quench area.

LS1SpeedAddict

iTrader: (9)

My car went 10.70 on motor with an nitrous converter and 9.69 on a 175 shot with that exact setup.