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      12-14-2013, 01:55 PM   #79
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Originally Posted by solstice View Post
The S55 is a similar engine to the S63TU?
It does sound like an impressive tune though. I need to look into this example because it could be the first one provided here that might support your claim of easy, large ECU flash power gains of the S55 and the ability run combustion pressure on street gas I've not been able to find other examples of alternatively that the stock turbos are capable of much more volume than that M utilizes. And it being a turbo M car makes it even more relevant but I need to see the details of the S63TU and the tune to know if it's potentially applicable to the S55. We are both speculating and using questionable science here but we should be able to still get a reasonable idea of the potential.
I take it you are not familiar with the turbo scene?

Modern European turbo engines are high CR, like the 991 Turbo S engine. Plenty of tuning. It's not like my old Sierra RS Cosworth with a 8:1 CR...

What specs of the S63 is of relevance in your comparison with the S55?
Which part of the N55/N54 is not relevant to the S55 since you don't think it's a good comparison of a high CR tuneable engine?

One of your previous observations was that the N55 is a low boost engine and that the S55 is high boost. But remember that the N55 is 300hp and the S55 is 430hp. For the N55/54 to go to 430hp the boost needs to be as high, or higher, as exemplified by the 20psi Switzer tune. That the N54 can achieve 600hp indicates a even higher boost level. Not sure if a 600hp N54 is possible on street gas.