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      10-23-2008, 08:26 PM   #12
drvai
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Drives: E92 M3 AW
Join Date: Dec 2007
Location: FL

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Thanks for taking the time for the answer, but I knew this. That's why I said "as close to".

Quote:
Originally Posted by BMRLVR View Post
For a short answer..... NO!!!

The reason a Ferarri sounds like it does has nothing to do with exhaust. The reason a Ferarri screams with such a high pitched tone is because all Ferarri V8 engines use a 180 degree or Flat-Plane crankshaft where the 4 rod journals (two rods are mounted to each journal in all V8's) are spaced at 180 degrees. the M3 V8 on the other hand uses a 90 degree or Cross-Plane crankshaft where the 4 rod journals are spaced at 90 degrees from one and other or at 0 degrees, 90 degrees, 180 degrees and 270degrees.

Mainly what affects the sound most about a Flat-Plane V8 is that each bank of cylinders are working like its own engine, or essentially like two four cylinder engines running simultaineously, hence the high pitched scream. This has to do with the fact that the firing order of the Flat-Plane V8 means that there are always two cylinders firing at the same time albiet one in each bank of cylinders. In a Cross-Plane V8 there is even spacing of the firing order of all 8 cylinders and never two cylinders firing at the same time therefore the lumpy tone that they have.

The main difference between the Flat-Plane V8 and Cross-Plane V8 is that the Flat-Plane V8 does not require large counterweights (the reduction in mass of the crankshaft due to the lack of counterweights equates to quicker revving, a higher rev ceiling, lighter weight and slightly more horsepower) on the crankshaft like the Cross-Plane V8 and a Flat V8 is much easier to tune with regard to Exhaust and Intake. The major drawback to the Flat V8 is that it is not as smooth or refined as a Cross-Plane V8 with regards to second order vibration. This is is why the Cross-Plane V8 is pretty well the universal layout when it comes to V8 Engines in mass production. Because Ferarris are more about performance then refinement they use the flat crankshaft due to its benefit in horsepower, weight, revability and simplicity.

I hope this helps!!
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