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Ls2 bottom end for boost?

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Old 06-15-2013 | 09:37 PM
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Default Ls2 bottom end for boost?

First of all, the goal is to get it setup for a reliable 10+ psi while remaining streetable. Boost will be provided by a Procharger D1 headunit. Heads are stock 243 with new springs. RPMs are planned to be kept within 6-6500 for drag racing, but i really dont see that being much over 6k.

Parts List
Crank - Stock crank
Rods - Eagle CRS6125O3D H-beam 4340 rods with 8740 rodbolds (390$)
Pistons - Diamond 11517 (This is a 4.030 bore piston, how do people feel about that on an LS2 aluminum block?) (653$)
Rings - Not sure what to go with here? (maybe the JE piston rings?)
Bearings - Clevite H series throughout
Main bolts - Either reuse stock or buy some arp?

Those pistons would have me at around a 9.77:1 compression ratio with the ls9 head gaskets. Is that way to high, or manageable for street use?

Any advice would be greatly appreciated guys.
Old 06-16-2013 | 09:26 PM
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You could go as high as 10.0 compression and be ok on pump with 10-12psi on forged internals.

If you were running a low power n/a engine I would say .030 over pistons is ok. For an fi setup with double digit boost levels I would want as thick of a liner as possible, so do a 4.005 piston.

I would also upgrade to arp 2000 rod bolts.
Old 06-17-2013 | 01:40 AM
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Originally Posted by redtan
You could go as high as 10.0 compression and be ok on pump with 10-12psi on forged internals.

If you were running a low power n/a engine I would say .030 over pistons is ok. For an fi setup with double digit boost levels I would want as thick of a liner as possible, so do a 4.005 piston.

I would also upgrade to arp 2000 rod bolts.
Thanks for the advice!
Any suggestions on a piston? Seems to be hard to find some in that diameter with a good dish that dont cost an arm/leg. I havent measured the bores yet, but potentially i could get away with a hone and run a stock bore piston?
Old 06-17-2013 | 07:16 AM
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Wiseco has that type of piston and is not too expensive, in the 6-700 range.

I wouldn't hone the block and then run stock bore pistons, that's just asking for trouble.



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