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5oo Hp 7 Psi Too Much

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Old 01-16-2006, 07:19 PM
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Default 5oo Hp 7 Psi Too Much

Stock 500 Hps B&m 420 Mega Blowers 93 Octane..can This Setup Handle 7psi . Go From 4 To 7 By Reversing The Pullys.. No Inercooler...
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Old 01-16-2006, 07:26 PM
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Default Re: 5oo Hp 7 Psi Too Much

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Originally Posted by chad1
Stock 500 Hps B&m 420 Mega Blowers 93 Octane..can This Setup Handle 7psi . Go From 4 To 7 By Reversing The Pullys.. No Inercooler...
I would take it out and hold it on the dash
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Old 01-16-2006, 07:32 PM
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Default Re: 5oo Hp 7 Psi Too Much

and bring a magnet
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Old 01-16-2006, 07:58 PM
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Default Re: 5oo Hp 7 Psi Too Much

Then you can drop all the pieces off at 80 Keane Ave W. Babylon NY and ZBerger will laugh at you and say why did you listen to JCPerf!!!!
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Old 01-16-2006, 09:06 PM
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Default Re: 5oo Hp 7 Psi Too Much

I'm taking that as 'not advisable'

Assuming pistons are the original ones.
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Old 01-16-2006, 11:57 PM
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Default Re: 5oo Hp 7 Psi Too Much

Hours on the engines?????

With stock head gaskets--No way, at least not for long.
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Old 01-17-2006, 09:33 AM
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Default Re: 5oo Hp 7 Psi Too Much

Chad,
I have been doing a lot of research on how much, reliable, boost to run on a marine engine. With 7 lbs of boost on your HP 500 engine your static compression is a little over 13 to 1. What I keep reading is where you want to set your engine for long term reliability is around 12 to 1 Effective compression (Effective compression is the calcuation of your compression ratio + the amount of boost you are going to run) . I just looked at a chart looking to answer your question the most boost you want to run with your stock HP 500 pistons is around 5 lbs. This will net you just over 12 to 1. If you go to Holley's web site and search around they have a bunch of blower technical information.
I hope this helps you out.
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Old 01-17-2006, 11:39 AM
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Default Re: 5oo Hp 7 Psi Too Much

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Originally Posted by JCPERF
I would take it out and hold it on the dash
Now that's funny $ht, I don't care who ya are

Greg, I don't mean to offend you but a boost level doesn't necessarily equate to a certain cylinder pressure. An engine that has a cam with 200 degrees of duration @.050" and pulley'd to 7 lbs of boost will not make as much cylinder pressure as the same exact engine with a cam that has 250 degrees of duration @.050" and pulley'd to the same 7 lbs of boost. A supercharger has to be thought of as another engine on top of the existing engine.
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Old 01-17-2006, 12:58 PM
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Default Re: 5oo Hp 7 Psi Too Much

Richard,
You may think my answer is funny, but I didn't see an answer from you.
Chad is looking for advice, and as I posted he can go to Holley's website and find what I am talking about.
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Old 01-17-2006, 01:11 PM
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Default Re: 5oo Hp 7 Psi Too Much

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Richard,
You may think my answer is funny, but I didn't see an answer from you.
Chad is looking for advice, and as I posted he can go to Holley's website and find what I am talking about.

He said JC's post was funny, not yours.


He also gave advice/information. Cranking Compression is related to cam duration and I'll add also to the amount of timing you are running. Holley's site might give some basic tech info, but Holley does not build engines.
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