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dannichols1474 dannichols1474 is offline
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Join Date: Sep 2019
Location: Milpitas, CA
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Originally Posted by dannichols1474 View Post
Today, I went out and turned the fuel pressure up from 55 psi to 60 psi.

Happily, the AFR did NOT change.
Dave (montauk) & Julian (Showdown) thank you for your comments.

When I think back yesterday and I changed the fuel pressure from 55 psi to 60 psi, the AFR DID change. The AFR at idle went up from 14.0:1 to 14.5:1 which had to be from an increase in dead time (latency) / decrease in fuel flow time due to the higher fuel pressure as the ECU commands a PW time that is dead time + fuel flow time.

I think I'll turn down the fuel pressure back to 43.5 psi (the gauge dial is course so probably 45 psi will be as close as possible) and see where the AFR comes in, adjust the VE table to achieve my desired 14.0:1 AFR and use the injector dead time Dave (montauk) found for the 0280155831 injectors and leave it alone.

I'll talk with Gary (the dyno tuner) about it on Tuesday before he runs the car on the dyno.
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Dan
1975 911 Carrera

"CIS to ITB EFI conversion" thread
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