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Re: Forge Piston Diverter valve? Posted by Larry West [Email] (#1140) [Profile/Gallery] (more from Larry West) on Fri, 2 Jan 2009 13:15:09 In Reply to: Forge Piston Diverter valve?, Nemo, Fri, 2 Jan 2009 10:05:22 Members do not see ads below this line. - Help Keep This Site Online - Signup |
The "standard" bypass valve opens when there is high vacuum in the inlet manifold (i.e. when Trionic has shut the throttle plate), and it bypasses the pressurized inlet air back around to the inlet side of the turbo compressor from the pressure side. The primary reasons for this are 1) it keeps already-measured air inside the engine, which lets Trionic meter things accurately and 2) it helps prevent potential bad things happening when you shut the throttle on all that incoming, pressurized air.
By contrast, a "blowoff valve" opens under the same conditions, but dumps the pressure overboard, outside the engine system. They are used commonly in racing, but racing uses primarily open-loop engine management systems, which don't really care about "already measured" air...
Look for a round, plastic device that has one large hose coming off the end with a much smaller hose off the opposite end, and one large hose coming off the side. That's the "stock" bypass valve.
Unless you've hotted up the motor with an ECU upgrade, or just like the "bling" of a stainless, chromed or anodized valve, the stock valve is more than adequate for its intended purpose.
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