crankshafts ???
05-31-2009, 08:48 PM
#1
crankshafts ??? what are the difference in lt1 crankshafts and gen1 sbc 1 peice rear seal crankshafts having a hard time finding and forged crankshaft for lt1 . i'm planning a 355 or 383 getting my block work done now need help with this i also read alot of problems with cast cranks and wonder if anyone has problems with the forged... also what can i spin a all forged 355 or 383 to safely ... with n20
05-31-2009, 08:49 PM
#2
As long as it's for a SBC with a one-piece rear main seal, it will work. There are no LT1-specific crankshafts.
Forged is always the way to go for N2O/boost.
RPM limit depends on a lot of things. If we rule out the valvetrain, transmission, a budget, and everything else, you could build a bottom end to survive spinning to the moon.
Forged is always the way to go for N2O/boost.
RPM limit depends on a lot of things. If we rule out the valvetrain, transmission, a budget, and everything else, you could build a bottom end to survive spinning to the moon.
05-31-2009, 09:06 PM
#3
kewl well i was goin to used forged h beams and forged pistons .. i got comp magnum rr 1.6 ratio magnum one peice push rods if i do the 355 i was thinkin bout goin back with the 503 or gm 847 duno but has anyone every done a 4 7 swap cam in a lt1 do they make it i know they do for sbc but lt1 being efi i duno it would be fairly straight forward swap 4 7 injector and plug wires ... ?
05-31-2009, 10:20 PM
#4
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Valve springs should be near the top of your list as a limiting factor for high rpm's. Most 4340 forged cranks are rated up to around 8k rpm, but thats just he crank and they all are different.
4-7 swaps do not work well with the LT1, it has to do with the intake and making certain cylinders run lean. Sorry I don't remember the specifics as to which cylinders got worse, but overall disadvantages outweigh the advantages when using an LT1 intake.
4-7 swaps do not work well with the LT1, it has to do with the intake and making certain cylinders run lean. Sorry I don't remember the specifics as to which cylinders got worse, but overall disadvantages outweigh the advantages when using an LT1 intake.
06-01-2009, 01:16 PM
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No, you want large journal it has to do with the size of the crankshaft where the rod connects to it. Idk if they even made small journal 1 piece I thought they were all 2 piece.
