Determining the correct blowoff pressure?

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Nov 12, 2012 | 09:48 PM

Chevyscoot

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From: North Texas

Determining the correct blowoff pressure?

What is the best way to determine the correct blowoff pressure.

Nov 13, 2012 | 06:09 AM

stevieturbo

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From: Norn Iron

with a blowoff pressure gauge ?

Nov 13, 2012 | 10:14 AM

imma_stocker

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From: Country

Turbo bov needs to be tuned for your setup which will require springs and shims for those pieces that use them. Tighten it up til you get a LOT of compressor surge, then loosen it back until it surges some without barking from full boost. FWIW, I spent a good hour getting mine right. Adjust, test drive, repeat until done.

S/C, I'd guess any time you let off the throttle in boost it should release some pressure. Just a guess though.

Nov 13, 2012 | 01:54 PM

killernoodle

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Adjust the blowoff valve so that it just barely doesn't open when the engine is idling. Any amount of boost in the charge pipe with the throttle closed should open it up Your car is going to be pulling vacuum at high rpms and will have no problem opening up the BOV when the throttle closes.

Nov 13, 2012 | 02:48 PM

LilJohn

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If this is for a Tial Bov.... just measure your vacuum at idle with a guage. Then tell them that result when you order.

Nov 13, 2012 | 04:09 PM

RedRocketZ28

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From: Madrid, IA

Not hijack but my question sort of pertains to this. Should the BOV be open or closed at idle? Mine is open and am running a RPS BOV. Is there any negatives to having the spring too light and having the BOV open at idle?

Nov 13, 2012 | 04:22 PM

stevieturbo

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From: Norn Iron

Quote:

Originally Posted by RedRocketZ28

With a turbo, it doesnt really matter. As long as it stays shut on boost, and responds fast enough when you close the throttle, that's all that really matters.

Unless of course you are still using the MAF then BOV placement and response can matter