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Old 09-05-2015, 08:19 AM   #20
jaykay
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Join Date: Sep 2009
Location: toronto
Posts: 2,668
Quote:
Originally Posted by The Radium King View Post
i think a 101 mm bore is the max (available to us common folk, anyway) so with a 3.2/3.4 bottom end the biggest you can go is 3.8. the m96 3.6 and the m97 3.6/3.8 got stroked, so they can go to 4.0 with a 101 mm bore. i don't think you can just drop the stroker crank in a 3.2/3.4 bottom end as the bearing races are different (possible, but lots of work?)? and, as stated, the longer stroke increases lateral load on cylinder walls = more scoring, which is the big failure mode on the m97 engines. fixed when Porsche went to a stronger liner with the dfi engnes. so, if you do go with a stroker crank, make sure you do the lne nikasil liner as well.

then there are the heads. there is some voodoo on the interchangeability of the various heads which jake has alluded to in the past, and perhaps if he reads this he'll add some content?

but by the time you've replaced the heads, paid $5k to bore the cylinders, and rebuilt the bottom end, i'd suggest you are well into the cost of a new engine (la dismantler has a 3.6 X51 Powerkit engine for $12k or something on ebay right now - X51 has hotter cams, better heads, dual oil pumps, improved oil baffle, etc.).
Yes X51 is another route to consider for.....not sure about all the interface issues and any weak points in that engine.....I think you have one TRK how do you like it?+
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