Can anyone post pics of thier return style regulator for me please!
11-04-2010, 06:36 AM
#11
The 8an should be fine for a single A1000, but don't forget you can never have too much volume. I'm not sure what your HP will be with that setup, maybe someone will chime in that has something similar. But I am willing to bet that is will put a smile on your face. :-)
Swift, the vacuum/ pressure line is to maintain a constant pressure at the injector tip inside the intake. When the engine idles, there is a vacuum, and when you are into boost there is a pressure. If you were to run a steady 60 psi of fuel pressure without the line, and 15 lbs of boost the tip of the injector would only perform as if it were at 45 psi.
Swift, the vacuum/ pressure line is to maintain a constant pressure at the injector tip inside the intake. When the engine idles, there is a vacuum, and when you are into boost there is a pressure. If you were to run a steady 60 psi of fuel pressure without the line, and 15 lbs of boost the tip of the injector would only perform as if it were at 45 psi.
11-04-2010, 10:00 PM
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On my 04' there was no vaccum reference on the FPR in the tank. 60psi constant idling/cruising. In boost the fuel pressure would drop on. Generally saw 50psi @ 10#.
11-04-2010, 11:34 PM
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Rick
11-05-2010, 12:44 AM
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The way I understand it the return-less systems use an IFR table that lowers (open time/duty cycle) when a low MAP is present (due to -pressure relative to atmosphere) and it increases in duty cycle up to std. time open at 101 MAP/atmospheric to compensate for the change in manifold pressure (Adds cycle time since less fuel will flow at Rail pressure versus Manifold pressure.
I'm not certain if a you can expand the table on a return-less system to include fueling modifications for MAP higher than atmospheric. Hence the Boost a Pumps and Magnavolts that increase pump voltage relative to Manifold Pressure.
11-05-2010, 11:49 AM
#20
Yep, the returnless fuel system uses a sloped IFR table to account for Vac in the manifold, where the return system is a flat, single value. The other thing with the returnless table is it only goes to 100kPa which is sea-level atmosphere and no boost, so when you get into boost, you have to have a VE table that is lying to get the proper AFR and what makes it even worse is the pump usually can't keep up the pressure either, dropping a little like you said yours does, so that make the VE table have to be off even a little more. Return, vac/boost referenced fuel system is the best way to go with boost, but returnless works ok too. 