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      04-03-2013, 10:32 PM   #21
mkoesel
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Quote:
Originally Posted by BigMacSmallFries View Post
Could we get scott26 to confirm this?
Probably not. We aren't likely to get such engine details until BMW is ready to release them, which will probably happen sometime later this year.

Quote:
Also, since this is a next generation motor, and unrelated to the M5/M6 v8, is it possible for the redline to be substantially higher than 7200RPM as found in those?
It is possible, sure, but not likely. Generally, higher RPM means less efficiency (its not necessily that simple of course, but typically that's how it works), and they are trying to maximize efficiency with their turbocharged engines.

Quote:
Originally Posted by Uli_HH View Post
It is almost impossible, that an I6 based on the N55 can attain an redline of 8.000rpm ... the only BMW turbo engine which would be able to do this, is an S63Tü based V6 - because of his square cylinder design.
The shape of the cylinder is not really important for max RPM. Rather, it is stroke length. The N55 and N63 have nearly identical stroke: 89.6mm and 89mm respectively. The 8000 RPM S54 has a similar stroke and Audi's V8 and V10 are actually 93mm and rev as high as 8500 RPM in some applications. Of course, those are all NA engines. The turbocharged McLaren engine has a very short stroke by comparison.

Quote:
Originally Posted by BigMacSmallFries View Post
But what if the distance between the cylinder walls on the updated S55 are much thicker allowing for a bore out? I wouldn't assume it would be the same as the N55.
That would mean a brand new engine architecture with high costs. The whole point of working with an existing engine as a basis is to use existing tooling and maintain compatibility with some existing parts such as timing assembly, accessories, mounts, etc.
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