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polizei polizei is offline
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Join Date: May 2007
Location: Collegeville, PA
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Quote:
Originally Posted by mb911 View Post
the picture looks right to me I would check to see what your brake booster line is connected to in the engine bay
Is the line that is T'd into the boost gauge line, the same line that would be running to the engine bay?

Quote:
Originally Posted by WERK-I View Post
Could there be a check valve in that line in the engine bay?
Jerry mentioned there is one as well. Wouldn't a check valve prevent positive pressure from going to the brake booster and in turn prevent a boost reading?

Quote:
Originally Posted by 911st View Post
Couple of things on a suck through.

This is a more typical way to set up a motor. New car makers do not to a blow through.

With the Carrera 3.2 the AFM gets pegged at around 180 rwhp of air flow and mostly is not used any further to determin fueling so it is the RPM table on the chip and the raising rate fuel pressure reg that determines your fueling.

The only time there is more CFM measured at the AFM between the two should be when you let off the throttle and the blow off valve opens and vents to atmosphere. With EFI the fueling is mostly stopped when the throttle is lifted so this should not be an issue. Worst case you will spit a little flame out the exaust.

Check w Todd about this as he is the expert. It should not make much difference.

If you want he can convert you to a boost sensing system which takes the AFM out of the system altogether and you get a program to map your own chip.
Excellent information. I've sent an email to Todd to verify whether the suck through method would pose any issues and to get some figures on how much his MAP solution costs.
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Andy - 1987 911 Carrera Coupe
Old 09-17-2008, 11:24 AM
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