Thread: Question the church !
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Old Jan 12, 2009 | 07:31 AM
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waldig
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From: VA
Talking Question the church !
Question the Church part #2

In my effort to understand the leaning out problem with my car I relearned a great many things. One of the most important is to “question “the conventional thinking and another is to QUESTION THE AUTHORITY…..Your success depends on it at times.

I looked at the factory manual to understand the fuel system and it showed a return type of fuel regulation system. I would have stopped at that point if I knew better, but I did not know or stop there.

I pulled off the plastic shield under the rear of the car below the passenger seat. The fuel pump and stock regulator / reside there. I have a few photos in my gallery under the fuel section for your assistance and review.

The fuel regulator is the larger of the two canisters and it has four pipes. One comes from the fuel pump ( inlet ), and there is an outlet on the opposite end that feeds the engine with fuel ( outlet ). The other two fillings are in the center of the canister on each end. The larger of these if the bypass line that feeds fuel back to the tank and bleeds off pressure to regulate the 60 psig pressure.

The remaining line is smaller and has a ¼” fitting and on MY CAR, THIS FITTING IS FACING THE DRIVESHAFT area. According to the manual this line appears to me to be a pressure line that regulates the bypass function inside the regulator. More pressure would cause the regulator to pass more fuel to the tank and limit the pressure rise.

You may wanna see my signature and look at the you tube video at this point.

I pulled off the regulator pressure line (1/4”) and got suspicious, no gas and no gas smell?????????????? Ok so I added a fuel pressure gauge to that line and fed 12 volts to run the pump. In this fashion I could shut it off like NOW if need be. Gas is energy and that is dangerous – never do anything that you cant get away from if need be and the ignition key is miles away if you need to turn it off. [0.1 CEU for safety training ]. The pump started and hummed but the gauge did nothing. I had added an air conditioning gauge to the fuel rail to monitor the pressure; at this stage it was 60 psig.

So the little pipe did not monitor pressure and set the regulator. Getting brave, I got an air gun and set it to 10 PSIG and injected the air into the little hole. TAAAA DaaA as I like to say the fuel monitor jumped up to 70 psig. Resetting the air gun to 20 PSIG my current maximum boost, the fuel pressure responded and went to 80 psig. For the Dennis the Menace types out there if you block off the return line the pump has a limit of about 110 psig, more on that later.

So the small line was connected to the vapor recovery tank in the same area and the little line is vented to keep the pressure constant with the atmospheric pressure - - - - I guess. In any event if I feed air pressure into the hole the pressure rises almost exactly 1 to 1 PSIG with the ¼” pipe signal.

Now I gets moving real good cause I can taste the success and feel hungry - - - like munchies hungry. I hung the fuel gauge on the windshield wiper with a wire tie and added 16’ of ¼ “ fuel line to the engine where I added an additional fitting to the manifold for boost. I hope to be getting different manifolds soon and will do it better then.

Driving was interesting as the car really pulled at the high end even though I saw only 70 – 72 psig on the fuel line. I did not lean out and the in car F/A gauge was a happy 12.8. Sorta success as I wanted the full 80 psig on the fuel, this is to be taken under study; it may be a lack of delivery capacity.

So I have scratched the surface and saved myself about 300$ by not getting the FPR and other parts. The fuel enrichment works but Ill need to get the data logger up and running to understand more, details will be provided as they develop.

Ideally we will be able to get a fuel air mixture that is dynamically compensated by the boost. This will eliminate the errors of just adding fuel based on the RPM only, for the boost is dependent on the amount of throttle opening and air density at that moment.

Your favorite lightning rod, Woody

 
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