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Old Tue, April 28th, 2009, 07:49 PM
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Jackpine Jackpine is offline
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Quote:
Originally Posted by soutthpaw View Post
Well You can't really look at boost as a percentage esp with diesels as there are quite a few diesels runing upwards of 50 PSI boost pressure
I don't think you're right here. Everything I've read on turbos says the good ones give a 50% boost, not 50 psi, but that since you don't get perfect efficiency out of it, you might see a 40% boost. 50 psi is about 3.4 atmospheres! That would be an enormous amount of air. You'd be burning 3.4 times the unboosted fuel volume just to maintain the correct A/F ratio!

And, there's simply no way a turbo could maintain that 50 psi boost as ambient air pressure drops. (How much boost would you get in space?) The boost value HAS to be a percentage of the ambient pressure, not a fixed pressure value.

I see I forgot to congratulate you on passing the 200 post milestone. :o I meant to, and I enjoy your thoughts.

- Jack
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