Can I replace ATI bypass with BOV?
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From: Los Angeles
Can I replace ATI bypass with BOV? I figure since the ATI bypass is before the MAF, I could replace it with a BOV that vents outside instead of back into the supercharger. Would there be any negative effects on performance by venting the air out? The reason I ask is because my friend has a turbocharged IS300 that got wrecked and she offered me her HKS Super Sequential BOV. It makes a sweet sound when it opens. BTW, it's going on my 5.3 Yukon with a Procharger that is pushing close to 10#.
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From: ohio
Re: Can I replace ATI bypass with BOV? I believe the reason for venting it back to the air cleaner is so that it doesnt pull unfiltered air into the intake tract. When the BOV is recieves vacuum it opens, and will open when driving under part throttle, sucking in unfiltered air.
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From: N. CALI
Re: Can I replace ATI bypass with BOV? A BOV does not work like a bypass valve, bypass valves are open all the time under vacuum, blow offs are not. So, when under normal crusing, the BOV will not relieve pressure correctly and the air will try to run backwards out of the supercharger
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From: Chi-Town
Re: Can I replace ATI bypass with BOV? </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by smokinTA:
<strong> A BOV does not work like a bypass valve, bypass valves are open all the time under vacuum, blow offs are not. So, when under normal crusing, the BOV will not relieve pressure correctly and the air will try to run backwards out of the supercharger </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">finally....someone else gets it
Everything ^^^ is true...except that SOME not all BOVs do open under vacuum conditions. However they dont open enough and flow enough air to not cause problems with the seals in the blower.
<strong> A BOV does not work like a bypass valve, bypass valves are open all the time under vacuum, blow offs are not. So, when under normal crusing, the BOV will not relieve pressure correctly and the air will try to run backwards out of the supercharger </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">finally....someone else gets it
Everything ^^^ is true...except that SOME not all BOVs do open under vacuum conditions. However they dont open enough and flow enough air to not cause problems with the seals in the blower.
Re: Can I replace ATI bypass with BOV? Compressor bypass valve (CBV)
In the CBV case, pressurised air is returned to the turbo compressor inlet for reuse. The valve is open under engine vacuum conditions, and closes firmly when positive (boost) pressure is present in the inlet manifold (or plenum chamber). As you change gear there is a sudden vacuum condition and the valve opens again, directing pressurised air back to the turbo inlet.
Blow-off valve (BOV) / Dump Valve / Vent valve
This valve type features an adjustable spring design to keep the valve closed under idle, cruise and boost conditions (eg 0.5 bar). Sudden throttle lift-off (eg 0.8bar) opens this style of valve to vent the pressurised air directly to atmosphere (and wooshtssh).
use whichever floats your boat
i dont see s/c seals having a problem at all with bov's.. if properly set up, a bov's discharge pressure will never exceed your maximum boost pressure, so its at most the same wear as occurs when you are wot.
In the CBV case, pressurised air is returned to the turbo compressor inlet for reuse. The valve is open under engine vacuum conditions, and closes firmly when positive (boost) pressure is present in the inlet manifold (or plenum chamber). As you change gear there is a sudden vacuum condition and the valve opens again, directing pressurised air back to the turbo inlet.
Blow-off valve (BOV) / Dump Valve / Vent valve
This valve type features an adjustable spring design to keep the valve closed under idle, cruise and boost conditions (eg 0.5 bar). Sudden throttle lift-off (eg 0.8bar) opens this style of valve to vent the pressurised air directly to atmosphere (and wooshtssh).
use whichever floats your boat
i dont see s/c seals having a problem at all with bov's.. if properly set up, a bov's discharge pressure will never exceed your maximum boost pressure, so its at most the same wear as occurs when you are wot.
