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Rb25det - Flat Spot Just Off Idle

Color_Of_Green
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Cubes Grand Master

Cubes

Posted
Posted

It really depends on how large the injectors are and if there's enough scope within the pfc's inj. map adjustment.

The pfc only allows adjustment of 0.49 to 1.49. Or something along those lines anyway. So as you can see by that there is only limited room for adjustment. In your case .54 is pretty damn close to the lower limit the pfc allows. :)

Within the datalogit there is a recalc base function, all though it has its flaws that too can be used to sort out the inj. trim function.

Color_Of_Green Enthusiast

Color_Of_Green

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Ahh thanks cubes, you're a champ.

Just to let your know, I disconnected the AAC and adjusted the idle screw but the maximum it would idle was around 800 rpm. I have my PFC idle setting on 850 rpm. I didnt go through the data init & idle learn as like I said before I dont have a datalogit yet so ended up putting the AAC idle back to where it was and reconnecting the AAC plug.

I would have though that the max idle rpm could be set higher than 800 via the AAC screw?

Color_Of_Green Enthusiast

Color_Of_Green

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Your aac sounds a little clagged. Might need to rip it off and give it a clean in carby cleaner/petrol what ever. :D

So did help the problem at all?

I actually forked out the $$$ for a brand new one a couple of months ago.. :dry:

As for the injector lag, I couldnt actually detect any differences between +0.00 and +0.08, and I was trying to do the math to find out what effect the difference in lag would have theoretically at say 7000RPM but I am not sure at what position in the induction cycle the injector fires [ would appeciate some input there ]. I am waiting on some books on EFI from amazon that should explain the theory to me as I am really guessing :(

Once I restore my IGN and INJ map from my last tune I will be able to tell you if what I have done has made a difference.

Cheers

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