Chris'stransam

iTrader: (7)

I was talking to the person that will be building my FI motor , and he suggested I should use a LS3 block stock bore with a 4" stroke with forged pistions. Is there any reason I should pick the ls3 block over the 6l iron block ? Are the cylinder longer on the ls3 ? the CI ddifferent ance would be from a 390-416 . 416 if I would use a ls3 block witha 4" stroke for got to mention I am using a novi 2200 with about 16-18 psi

DEFYANT

You could get a few more cubes out of it, and its lighter, those are the only differences I can think of.

speedracer5532

iTrader: (8)

The LS3 block is lighter and plenty strong enough....no reason to go with the 6L iron block.

redtan

iTrader: (5)

Except price

You can easily make up the benefit of a lighter block by running half a lb more of boost. Unless this is a dedicated road race car where every lb of curbweight counts, I'd do the iron block for that kinda power.

87silverbullet

iTrader: (11)

I would go LS3 block but I wouldn't use a 4.000 stroke crank. I would use a 3.800 to a 3.900 strok crank to get a better piston in the bore. Callies sells a 3.8 something stroke crank. If you went with a 3.800 crank and a 4.065 bore you will have a 395 cu in motor. Trust me, you won't miss those 21 cubes under boost and you will have a motor that will have more longevity

I8UR4RD

iTrader: (16)

Iron is said to be stronger. And these guys are steering you the right way on the ci. Bigger wont necessarily mean more power in the boost world. Strength is key. The internals can be beefed up if you plan the motor out right. 364-390ci would be perfect. more than enough to run 8's with enough boost.