Ease up on the accusations and borderline insults, you are massively guilty here of misreading/misinterpreting my words and driveling them back out with a completely false interpretation of my very clear statements. Really, shape it up.
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Originally Posted by Boss330
It seems that you think I believe the V8 warble comes from an uneven firing sequence per crank rotation/angle... And since it doesn't I'm wrong.
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No, I understand exactly where it comes from. No need then and no need now for such a treatise. It's real simple - cross planes have consecutive firings in one bank of the V, flat planes does not. Both designs have an equal crank angle between combustion events. No need to write a book to explain this. And thus, as I said, it is more about those firings being routed to the same header and section of the exhaust.
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Originally Posted by Boss330
In a flat plane crank V8 all 4 pistons on the same bank are in sync.
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Absolutely not, I know you know this, but your language is entirely incorrect/sloppy here.
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Originally Posted by Boss330
They are grouped 2 and 2 together with 180 degree of crank rotation separating TDC for the two groups.
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Yes, exactly.
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Originally Posted by Boss330
There is NO way that the "state of tune" can eliminate the 2 cylinders firing out of sequence, neither can a exhaust system after the collectors on the headers.
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I never said that at all, that is 100% misreading and reading into what I wrote. Again, I said that overall state of tune (perhaps loosely given by specific output), along with redline and along with exhaust are more important factors than crankshaft geometry while under load (actually driving). I also said that some exhaust routing trickery could basically eliminate the cross plane V8 warble and we agree on this.
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Originally Posted by Boss330
It has to be done before the collectors, just as BMW does on the S63tu and Ford did on the GT40.
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Yes, agree.
"Warble", a good/accurate term, is fundamentally a low frequency phenomena. I contend that at any significant use rpm, although some folks may be able to tell the difference between flat and cross plane V8s, the differences substantially diminish. Yes, the effect is still present as the same basic phenomena is happening, just sped up. But compared to idle it is undoubtedly diminished. How about tuned cross plane V8 Corvettes? Why do they not sound much like an M3 V8 (again cross plane). We've had this debate before but I claim that at high load and high rpm an M3 with nothing more than a cat back sounds closer to a V8 Ferrari than a V8 Corvette. The fundamental reason is the redline, exhaust system differences and state of tune (compression ratio, specific output, etc). Sound is fundamentally determined in spectral content, that is by the number of combustion events per second, higher rpms gives correspondingly higher frequencies simply NOT present at lower rpms. This is a major effect.
Lastly I also contend that turbo charging an engine gives it a huge change in sound and it also makes a bigger difference to overall sound than flat vs. cross plane (again while under load).