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911st 911st is offline
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Join Date: Jan 2004
Location: Sacramento
Posts: 7,269
Good idea on the Group B's.

I do not believe lift is really what lets these motor's breath unless the ports are opened up a bunch (like 39mm). It is more the cam timing and duration.

Has anyone else had the motor apart before?. You might CC the heads? In the past it was popularized in Bruce Anderson's book to take 1mm off the heads to bump the compression a half a point. This still worked with SC cams. If this was done it would be costing you some clearance.

Also, have you put better rods in it. The stock rods should not be used much past about 6700rpm.

After the Group B cams my vote would be for new light weight J&E turbo Pistons with a little more compression. This might help make up for some of a big cams loss of effective CR and allow a safer margin at RPM.

Not an expert, must my thoughts.
Old 11-07-2010, 08:19 AM
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