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911st 911st is offline
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Join Date: Jan 2004
Location: Sacramento
Posts: 7,269

Originally Posted by full quack View Post
...I removed the decel valve, and re-routed my dizzy vacuum advance hose directly to the throttle body, by passing the thermo switch...
Glad it is working for you.

However, here is my two cents:

On a 914 the deaccel valve is nothing but a smog device and an irritation.

On a 930 it helps with several things besides emissions.

It helps keep the rpm's (and boost) up a bit between shifts.

It also acts is a mini BOV in that it passes air around the throttle plate and thus less stress is on the turbo between shifts (especially if the BOV fails).

It also helps reduce over-swing of the metering plate with shifts. Even with the bypass this over-swing creates a brief lean condition when getting back in the gas.

There is a Porschee WUR damper that can help with this and on the later C2 Turbos they actually added a special bypass valve to the Fuel Distributor to lessen this issue. RUF used the dampener on the BTR and Porsche used it on the 930 SE.

These are probably not big deals as many seem to have been happy with removing the De-accel valve. It dose improve preserved throttle response as the motor will de-accel faster.

On the dist bypass. Do you have the two connection pot? Did you bypass the solenoid to?

Last edited by 911st; 09-30-2010 at 02:18 PM..
Old 09-30-2010, 02:07 PM
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