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Re: Forge BOV Posted by Gene N [Email]  (#1094)  [Profile/Gallery]
(more from Gene N) on Tue, 10 Jun 2008 07:43:39
In Reply to: Forge BOV, Danah, Tue, 10 Jun 2008 07:20:57 Members do not see ads below this line. - Help Keep This Site Online - Signup |
The purpose of the bypass valve it to keep the pressure on the intake tube from spiking when the throttle is closed. If the pressure gets too high, it can cause the turbocharger to stall. This puts extra pressure on the turbocharger thrust bearings, increasing wear, and causes turbo lag when the throttle is opened again. Venting the pressure back to the intake stream (bypass valve) or to the open air (blow off valve) keeps the turbocharger from spinning down, especially between shifts. Venting the pressure into the open air does not harm the engine, but it does make more noise. I am not quite clear of the benefits of not sending the air back to the input stream, other than the slight restriction caused by the recirculation plumbing. The complaint on the standard BPV is that at the higher boost pressures generated by a modified engine(above 20 psi?), the BPV leaks some of the precious boost.
I think that its big attraction is the whoosh sound it makes.
posted by 157.127.12...
, Tue, 10 Jun 2008 07:43:39 <-- Viewing This Message
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