toss the throttle body completely?
JShadzi at aol.com
JShadzi at aol.com
Tue Jan 30 13:04:15 EST 2001
This is actually a great idea, and how the early A1 quattro race cars were set up. If you notice in early pictures of those cars, they are still CIS, but the airflow meter is located above the drivers side pedal assembly...why? Because the throttle was directly tied to the air flow metering arm, acting as a huge throttle body directly correlated to the throttle position. The problem is, however, while this works great on a race car that spends 95% of the time a WOT, on a street car the factory set up results in the best driveability.
In a message dated Tue, 30 Jan 2001 11:23:46 AM Eastern Standard Time, DeWitt Harrison <de at aztek-eng.com> writes:
<< A fellow posted (Turbobricks) the results of a little experiment he
performed on his Bosch CIS equipped ovloV turbo motor. I thought
it was a clever thing to try though probably fraught with difficulties,
such as passing emissions testing. What says the list? What is
the basic conceptual flaw in redefining the air sensor plate to be the
> I tried this today. I wired the throttle wide open. Drilled a hole in the
> top of the 90 degree hose fitting at the fuel distributor ( directly above
> the center of the sensor plate). A rod (phillips screwdriver) was slid
> through the hole until it just touched the sensor plate. Started car. Sensor
> plate became the only throttle.I had to hold the screwdriver down at idle.
> Allowing it to rise increased engine speed. There was quite a bit of force
> pushing up on the screwdriver. It took some practice but I had it acting
> like a throttle. The response seemed much better. I can't think of a reason
> why the drivers foot could not be directly tied to sensor plate. If the
> original setup could be compared to a constant velocity carburator then this
> ,perhaps, could be likened to a Holley with accelerator pump. An actuator
> (cable??) could be rigged tha allows the sensor plate to rise (open) as
> apposed to forcing it open. This would keep the mixture correct or perhaps a
> little on the rich side during acceleration.
> What am I overlooking ? Will this work?
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