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Walt Fricke Walt Fricke is online now
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Join Date: May 2004
Location: Boulder, Colorado
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Afterburn - I think the boxer configuration reduces balance issues compared with an in-line motor or a V motor. But the reciprocating parts (pistons) and rotating parts (crank), and both (rods) still need to be balanced, which Porsche does (or did) by grouping parts of roughly equal weight together - some engines had heavier rods, some lighter, for instance, though all in any engine were within some spec of each other' weight.

I'd venture to say that for ordinary street driving, if you rebuild a 911 engine and the pistons are good you don't need to have them balanced. If the crank measures out, it doesn't need to be balanced. Rods might benefit from balancing if you have them reconditioned, but the shop might well have that in their normal price for that work.

One thing you can do is line up your parts so the heaviest ones are closest to the flywheel, and then get lighter as you go out. I don't know if that will work on a straight or V motor, though

If you are going to hot rod the motor, well of course you will have everything balanced to a gnat's ass - that's just what we do, whether it makes much of a difference or not. Though if you are going to spin a 6,000 rpm motor to 8,500 rpm, a better balance job is a pretty good idea..
Old 03-01-2018, 10:36 PM
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