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Originally Posted by Westersund
High compression, boost and pump gas don't mix that well.
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My point is that these are dated generalizations that are spread over forums with little factual basis. Fuel injection has become precise and dynamic, and a centrifugal supercharger produces lower discharge temperatures than a twin screw at the same boost levels (as I've shown with thermodynamics). No offense is intended of course, but I'm looking more to answer "why" I should go with a specific CR other than that's what others have done (which is not always the best way to do things).
"Why" could be answered with, "What's the maximum safe cylinder temperature in which to inject 93 octane fuel?" I can calculate supercharger discharge temps, make an estimate (with buffer) for aftercooler efficiency, and then estimate cylinder temps due to CR. Obviously there will need to be a margin of safety due to cylinder hot spots, extended use, and so on.