well i found a set of pistons for the 3.903 bore that match my rotating assembly and came out of a daytona prototype motor

so i should be good to go

ok so poinions ls1 or 5.3 bored????
which would be the strongest

 

with the higher cylinder pressures of either heavy FI or lots of nitrous, I'd do the iron block. Hell, you're in a 5k lb truck, whats the 80 lb difference in block anyway...

 

yea the weight isnt the issue im wandering which would be stronger??

even with the 5.3 bore that much its still stronger than the ls1 block?