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drmatera drmatera is offline
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Join Date: Aug 2009
Location: Nicholson, Ga
Posts: 2,160
my thinking when it comes to fuel pressure regulators is that you want the pressure to decrease at idle/cruise (high vacuum) then increase over base pressure as boost increases because the boost in the manifold is fighting the fuel trying to exit the injectors.

45psi of fuel pressure fighting against 15psi of boost in the intake will significantly decrease fuel flow. So having the fuel pressure follow boost pressure will keep the injectors flowing at thier potential. Having it this way will help you control the inectors better at idle. I'm running the 60LB injectors, the problem isn't my EFI system it's that the injectors have a minimun duty cycle ( 1.5%). when you go below that it becomes unstable and causes a rolling idle. I'm going to switch to 80LB injectors in my car as they can be idled down to .5 %. Since i'm running E85 my 60's are at 100% now, so the 80's will work great for me.

If I keep injector Dc at 1.6% I get a rock steady idle and 13.9 - 14.2 a/f ratio. Cruise I can see 14.9-15.3 a/f without issue.

Are you running a dizzy or the EDIS for ignition?
Old 05-06-2010, 11:28 AM
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