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      10-01-2013, 05:19 AM   #132
mkoesel
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Quote:
Originally Posted by Boss330 View Post
As I wrote in a previous post, yes it's more complex than just one factor. But generally speaking a high revving low torque engine will be a oversquare engine like the 458 or a F1 engine. A low revving high torque engine will usually be undersquare. There are exemptions like the S54, but piston speeds are at the high end which is not good for reliability/wear.
Note that the V8 in the 458 is also an exemption as it makes more torque per liter than any other engine currently on the market.

If we go the route of subjectivity and look just at the "normal" non-performance cars out there with typical engines, I think we may indeed see a tendency for the under square engines to show slightly higher peak torque and at a slightly lower RPM than those with over square geometry. But, we are talking about an M engine here. Plus as swamp notes, road car engines are all so close to square, relatively speaking, that there is little variation in geometry to begin with.

Quote:
I guess we will have to wait on BMW to release details of why they went this route (if info is correct). Maybe we all have the wrong take on why they did it
For the record I still haven't been able come up with a truly compelling reason which is why I remain skeptical.
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