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Formula? Boost vs HP gain??

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Old 09-30-2006, 11:12 AM
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Default Formula? Boost vs HP gain??

Is there such a formula?

Thanks

Old 09-30-2006, 11:28 AM
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This might help assuming your air/fuel ratio is correct..

http://users.erols.com/srweiss/calchpb.htm
Old 09-30-2006, 01:36 PM
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We did alot of dyno testing on a 377 single turbo at everything from 3.5 to 18 psi boost. The power was remarkably close to NAhp*(14.7+boost)/14.7.

Mike
Old 09-30-2006, 02:34 PM
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Hmmm. Interesting link and calculator.
Old 10-01-2006, 10:23 AM
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Thanks very much!!

Old 10-01-2006, 11:18 AM
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I plugged in some stuff using 375 crank na hp for the engine parts and the results were anywhere from 930 to 1100 hp.
Old 10-01-2006, 12:54 PM
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I started with 450 N/A and it shows 1000 hp at about 18 psi. I put 430 rwhp to the wheels N/A with 11:1, now I have 8:1, I wonder how much power I lost? Should be close I think.
Old 10-01-2006, 01:47 PM
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I punched in my numbers and the results were "about" what I expected. Guess proof will be on the dyno when all is said and done.

Yup,, you can just add boost to the formula and HP sky rockets!!
Old 10-01-2006, 01:56 PM
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well, i know when we play with the vipers it's usally about 30rwhp per # of boost. this works out pretty good. I would think that the displacement would have something to do with that though so maybe 25rw/#?
Old 10-01-2006, 07:31 PM
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Originally Posted by nitrorocket
I started with 450 N/A and it shows 1000 hp at about 18 psi. I put 430 rwhp to the wheels N/A with 11:1, now I have 8:1, I wonder how much power I lost? Should be close I think.
I've seen a pretty consistent 5% power gain/loss for every full point of compression change. So, dropping from 11 to 8, nets you a 15% loss. That's about 365 rwhp at 8/1.

Mike
Old 10-02-2006, 01:13 PM
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I was figuring 400 crank hp for my longblock (at the most). Might be as low as 375 crank hp but I'm thinking 350rwhp.



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