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      12-14-2013, 12:57 PM   #73
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Originally Posted by solstice View Post
Boss330 do you know the boost for these tunes?
Remember the N54 has the same CR as the S55 but run very low boost giving it high tuning potential on stock fuel. You have to check the combination of CR and boost. The S55 is high on both making me doubt that there is much more to be have on stock fuel. You can of course get more hp on the same boost but that means higher rpm and that in turn means large blowers that can generate the large air volume needed to support the pressure at high rpms.
No I don't know the boost levels, but a rule of thumb is that a boost of 0,5bar is a 50% increase in power. At 0,5 bar a 2l engine is as powerful as a 3l engine (at a similar state of tune). So a 100hp engine makes 150hp at 0,5bar boost (less in the real world as compressing air creates heat which makes the air less dense, hence intercoolers).

But I don't get your logic on the N54 vs S55 comparison.
The N54 makes 300hp at 0,5 bar boost
The S55 makes 430hp at a undisclosed boost level (assuming both engines have stated hp according to DIN/ISO/EU standards)

Both have the same CR.

My guess would be that the S55 makes 430hp at 0,9-1bar of boost. A tuned N54 will also be at those boost levels if tuned to 400+hp.

If the N54 can make 6-700hp at the same CR as the S55, I don't understand why the S55 shouldnt also be able to do the same?