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Old 09-20-2008, 09:00 AM
brad black brad black is offline
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Join Date: Oct 2002
Location: melbourne, australia
Posts: 2,145
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a 1036 is with 2mm bigger bore - it's only 40cc bigger, or 4%. if the pistons are the same weight or lighter then there's no change in crank reliability. and the gearbox, etc, aren't going to notice an extra 4%.

i did a 1026 (900/st2 crank) that i didn't see the point of as it was a perfectly good 996 to start with, but if you were rebuilding a 996 down to crank out level then it's not a bad way to go. you add another std 0.6mm base gasket (2 in total) and the squish is then bang on 0.90 - 1.00mm and the comp around 12.7, no clearance issues, good belt tension with the heads 0.6mm higher, same piston to valve clearance as before - it's a good way to fix the squish and comp. still undervalved, but it should make a bit more than a comparable 996, again without stressing anything. you could pull the limiter down a bit for the extra stroke if you wanted to.

foggy's motor has the clearance issues with the 1000 crank, but apart from that i don't think there'd be any reliabilty issues. it's really revs that kills them, and with a 1080 peaking at 8,000 it's not going to get revved hard.
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