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Old 12-23-2010, 03:55 PM   #1
mtdave2
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Vacuum reading.

What are you guys getting for a vacuum on your 350 at idle? I was at 13 inches, but after plugging some leaks, I am at 17 now. Fresh 383 motor.
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Old 12-23-2010, 05:16 PM   #2
Fitz
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Re: Vacuum reading.

You didn't say what cam you're running but for a ZZ4 383 that's a bit high. For a milder cam 17-18 is about all you will get.
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Old 12-23-2010, 06:12 PM   #3
LONGHAIR
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Re: Vacuum reading.

It's kind of a "not fair" comparison. Assuming no leaks, the vacuum is mostly dependant upon the cam you choose, and a little on the compression ratio.
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Quote:
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As for reading directions...
The directions are nothing but another man's opinion.
Learn from the mistakes of others, you won't live long enough to make them all yourself...

Bad planning on your part does not necessarily constitute an instant emergency on my part....

The great thing about being a pessimist is that you are either pleasantly surprised or right.
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Old 12-23-2010, 08:11 PM   #4
mtdave2
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Re: Vacuum reading.

http://www.summitracing.com/parts/CCA-CL12-234-2/

Duration 256/268, Lift .447/.454
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Old 12-23-2010, 08:26 PM   #5
Fitz
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Re: Vacuum reading.

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Originally Posted by mtdave2 View Post
http://www.summitracing.com/parts/CCA-CL12-234-2/

Duration 256/268, Lift .447/.454
That's a pretty mild cam so 17-18 is about right.
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