I completely agree that the S65 sounds much closer to the Ferrari flat plane crank engine, which is down to rpm in particular.
I think we just emphasise different traits to the engine design. For me, there is two separate V8 designs: Cross plane and flat plane. The rest is, for me, just variations on a theme depending on what use the engine is intended for (i.e DOHC, cam in block, 4 valve/2 valve etc.). You can change that hardware on both designs and it will obviously change the engines characteristics, but no matter what you change of other hardware, a cross plane crank and flat plane crank engine will still be very different. You can tune a cross plane V8 to the same specific output, but the flat plane engine will still have superior response and exhaust scavenging. Leaving room for more power and a sharper response. There IS a reason F1 V8 engines, and the P65, use a flat plane crank.
The S65 and P65 is a really good example that validates the point about the importance, and reasons, to use a flat plane crank on a engine where maximum power and response is of importance.
These two vids illustrate the difference between a cross plane and flat plane crank engine. Notice how you have two adjacent cylinders firing in sequence on the cross plane crank engine. This is what gives the V8 that uneven, burbly sound, and causes exhaust scavenging issues.
I'll finish off once again by quoting Ferrari:
Quote:
Eight-cylinder engines with a 90 degree angle between their cylinder banks are a relatively recent addition to Ferrari history.
Apart from the engine sported by the 1956 World Championship-wining F1 car, which Ferrari inherited from Lancia after the latter pulled out competition, and the one mounted to the 248 sports prototype in the early 1960s, it was 1973 before a Ferrari would be powered by an engine with this specific architecture.
Characteristically flat-plane crankshaft engines have a crankshaft with crankpins angled at 180 degrees to each other or "flat" i.e. on the same plane.
Generally speaking V8 engines have a 90 degree angle between the cylinder banks with each crank pin offset at 90 degrees from the adjacent ones i.e. they are "crossed" at 90 degrees. Hence the cross-plane name. Whether a flat or cross-plane crankshaft is chosen depends on what kind of performance is required. To get maximum performance from the engine, the flat-plane must be used but for all-round functioning the cross-plane is best. This why all Ferrari V8s engines (from the 308 to the 328, the 348 to the 355,the 360 to the 430,and the special high performance GTO series, the F40 and the recent California, our first front V8) use a flat-plane crankshaft.
The advantages of the flat-plane crankshaft over the cross-plane one can be summarised as follows:
A flat-plane crankshaft is lighter than a 90-degree, or cross-plane crankshaft, and, having a lower rotating mass than the latter, provides sharper response as well as allowing higher maximum revs, useful when seeking higher power outputs. Another advantage of the flat-plane crank is that it allows more efficient exhaust manifold design.
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http://www.ferrari.com/English/GT_Sp...raftshaft.aspx