Fuel pressure setting/functionality at WOT
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Car: 1986 IROC-Z
Fuel pressure setting/functionality at WOT
I have read that at WOT, the car goes into open loop and the fuel pressure is not controlled by the computer; it is only controlled by the setting of the fuel pressure regulator. Now, with an adjustable fuel pressure regulator, the car may not have the proper air/fuel mixture at WOT.
I don't know if the computer adjusts the fuel pressure regulator directly, thus meaning that it can decrease and increase pressure. When setting an adjustable fuel pressure regulator, do you want to set it to run optimally at WOT, then let the computer change that setting for regular driving?
I don't know if the computer adjusts the fuel pressure regulator directly, thus meaning that it can decrease and increase pressure. When setting an adjustable fuel pressure regulator, do you want to set it to run optimally at WOT, then let the computer change that setting for regular driving?
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Car: 88 GTA
Engine: modified L98
Transmission: 700r4
Axle/Gears: 3.27 9-bolt
The computer does not control the fuel pressure at all. It's all done by vacuum. (If you look there is a vacuum line running from the plenum to the FPR). The stock regulator has a spring inside of it that controls the fuel pressure at WOT. The presence of a high vacuum (low throttle position) during normal driving will lessen the fuel pressure.
The aftermarket AFPR's come with a screw that allow you to effectively adjust the base setting of the spring pressure (by setting the preload on the spring). The vacuum hose is still hooked up, and still changes the fuel pressure accordingly.
You want to set the AFPR so that you get best performance at WOT, and let the vacuum adjust it for normal driving just like the stocker did.
The aftermarket AFPR's come with a screw that allow you to effectively adjust the base setting of the spring pressure (by setting the preload on the spring). The vacuum hose is still hooked up, and still changes the fuel pressure accordingly.
You want to set the AFPR so that you get best performance at WOT, and let the vacuum adjust it for normal driving just like the stocker did.
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Re: Fuel pressure setting/functionality at WOT
Originally posted by blue86iroc
I have read that at WOT, the car goes into open loop and the fuel pressure is not controlled by the computer; it is only controlled by the setting of the fuel pressure regulator. Now, with an adjustable fuel pressure regulator, the car may not have the proper air/fuel mixture at WOT.
I don't know if the computer adjusts the fuel pressure regulator directly, thus meaning that it can decrease and increase pressure. When setting an adjustable fuel pressure regulator, do you want to set it to run optimally at WOT, then let the computer change that setting for regular driving?
I have read that at WOT, the car goes into open loop and the fuel pressure is not controlled by the computer; it is only controlled by the setting of the fuel pressure regulator. Now, with an adjustable fuel pressure regulator, the car may not have the proper air/fuel mixture at WOT.
I don't know if the computer adjusts the fuel pressure regulator directly, thus meaning that it can decrease and increase pressure. When setting an adjustable fuel pressure regulator, do you want to set it to run optimally at WOT, then let the computer change that setting for regular driving?
As far as fuel pressure its pretty much only a WOT tuning devise.. Being as I've experienced both I'd recommend prom tuning over an AFPR, and thats even considering that I made my own for the price of a bolt.
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