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Hi Guys

Has anybody tried fiddling around with the injection firing angle degrees. The car has been dynoed, made 350bhp on pump fuel which is enough for what i need. What i noticed is that it is using much more fuel , apart from the over run fuel, i was looking into other things that could use alot of more fuel.
Infact i locked the fuel and timing on idle at around 950rpm, and took some readings for different injection firing angles. the best result was at -90 . Lambda fell by 0.4, this shows more fuel being burnt. It also corrected a throttle response issue that i had and couldn't fix with the fuel pump%.
The problem is that this is at idle.
I don't know how i can work out the rest of the map.

Any help even with a std map would be very helpful.

Thanks and regards
Cpur

The way to find it is exactly as you have done, but on a dyno.
You can use the full 20x14 map for this.

If you have the knobs box you can easy swing the injector timing with the knob and see directly what it does, I did this on the motorway with an assistant to find the timing that made it the richest, and then re adjusted the map weaker back to my target AFR.
Unless you have very very large injectors timing doesn't appear to make any difference at full throttle.
But to be honest doing all of this is probably not going to save you more than 2 mpg.

Thanks for the replies.

Alex since the car is only for racing and will not undergo Mot or any kind of emmision test, i think if i go to my tuner to dyno for best inj angle he would show me the way out....
Maybe i am being too fussy.

Rob Stevens . Since the car is not a road car, mpg is not my biggest concern. I hate that i changed to a much more versatile ecu from factory , and these things where not set by the tuner. His regards was power. So i give him no fault. The injectors are 1000cc .
From your experience if -90 is good at idle, will it be good that i fill up the map maybe going to -120 at 7000rpm. Does this parameter only need changing with rpm or even with load?


Thanks and regards
Warren

It is generally regarded that the end of injection should occur before the intake valve opens.

So start there, test...to find what works best for you.

Guys. So the injection angle is variable between -359 to +359 from tdc.

I have std cams on the yb . So the the opening is at 6 and closing is at 55

So the intake opens at tdc -180 for compression, -180 intake, -6 cam time.
So if i need the injection to be ready then i need to input + 354.
Is this correct?

Thanks
Cpur