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DRPHIL914
Just had my first good drive since putting the A/F meter in the car.
Once warm , idle is about 11.5 . And when running g out about 45-60 average is 13 and w.o.t. closer to 14.
So for a.d-jet 75 2.0, running premium lead free gas(91 octane) what is correct ?
Black22
I can't tell you how to adjust Djet (I run Ljet), but 11.5 @ idle is pretty rich.
dlee6204
And 14 @ wot is a bit lean
ConeDodger
QUOTE(Black22 @ Apr 4 2014, 08:11 PM) *

I can't tell you how to adjust Djet (I run Ljet), but 11.5 @ idle is pretty rich.


I dis agree.gif

Idle is rich for a reason. There is no cooling air to cool the heads. These engines are Air and oil cooled.

Those numbers are pretty much spot on, with WOT maybe just a little lean. But, that said, I wouldn't mess with it if it runs well. You spend very little time at WOT...

The theoretical number you seek is 14.7:1. lower is richer, higher is leaner. I hear, you want to move richer with the lead free alcohol blended fuels but not much.
brant
You need more fuel at wot.
14.7 is not right for an air cooled motor at
Wot. And 14 is lean.
12.5 to 13 is correct at wot.
ConeDodger
QUOTE(brant @ Apr 5 2014, 02:58 PM) *

You need more fuel at wot.
14.7 is not right for an air cooled motor at
Wot. And 14 is lean.
12.5 to 13 is correct at wot.


agree.gif but, it's probably a street car. His only adjustment is for idle. He can always make it worse. sad.gif
ConeDodger
Wait, check your fuel pressure...
malcolm2
QUOTE(Philip W. @ Apr 4 2014, 10:21 PM) *

Just had my first good drive since putting the A/F meter in the car.
Once warm , idle is about 11.5 . And when running g out about 45-60 average is 13 and w.o.t. closer to 14.
So for a.d-jet 75 2.0, running premium lead free gas(91 octane) what is correct ?


I checked mine a couple weekends back. IIRC I got 17-18 at idle. 13 - 14 a 3000 rpm. And 13.5 - 12.5 under load (hills and accelerating) at about 4500 rpm. Mine is a 1911 L-Jet ( AFM gog adjusted) fuel was 93 oct pure gas, no ethanol.
ConeDodger
QUOTE(malcolm2 @ Apr 5 2014, 04:58 PM) *

QUOTE(Philip W. @ Apr 4 2014, 10:21 PM) *

Just had my first good drive since putting the A/F meter in the car.
Once warm , idle is about 11.5 . And when running g out about 45-60 average is 13 and w.o.t. closer to 14.
So for a.d-jet 75 2.0, running premium lead free gas(91 octane) what is correct ?


I checked mine a couple weekends back. IIRC I got 17-18 at idle. 13 - 14 a 3000 rpm. And 13.5 - 12.5 under load (hills and accelerating) at about 4500 rpm. Mine is a 1911 L-Jet ( AFM gog adjusted) fuel was 93 oct pure gas, no ethanol.


Don't drive it till you dial up the idle...

Or, don't idle!
DRPHIL914
Guys, thanks for the input. I've had a busy day painting house! I do have the ability to adjust my mps and have a good understanding of how to adjust it. Right now when cruising at about 3000 rpm its around 13 - 13.5 which is what I seem to remember is pretty good. I had read that 14.7 was the theoretical neutral. But I think that's too lean for air cooled motors. My timing was a bit off and so idle was a bit rich at about 10.8, once adjusted that came up to about 12-. So I think I'm o.k.. if I get the mix down under 14 at wot. I plan on driving it a few weeks and then che king the plugs also .Oil temp yesterday after a 30 minute driive at 82 degrees out was about 185-190. Will see how that goes when its 95 out!
Black22
QUOTE(ConeDodger @ Apr 5 2014, 03:51 PM) *

QUOTE(Black22 @ Apr 4 2014, 08:11 PM) *

I can't tell you how to adjust Djet (I run Ljet), but 11.5 @ idle is pretty rich.


I dis agree.gif

Idle is rich for a reason. There is no cooling air to cool the heads. These engines are Air and oil cooled.

Those numbers are pretty much spot on, with WOT maybe just a little lean. But, that said, I wouldn't mess with it if it runs well. You spend very little time at WOT...

The theoretical number you seek is 14.7:1. lower is richer, higher is leaner. I hear, you want to move richer with the lead free alcohol blended fuels but not much.


I dis dis agree.gif

11.5 at idle is washing down cylinders. I agree the fuel helps cool the motor, but that cooling can be done at 13 -13.5.

11.5 is not only rich for idle but WAAAAY rich. My car doesn't even hit 11.5 at any point in the curve!

My set up is 13.9 at idle, 12.5 at WOT and 15.5 max lean during a freeway cruise (basically just enough throttle to maintain speed. My temps max out at 360F during 85mph freeway speeds and as soon as I come to a complete stop at the end of the off ramp I'm at 300F.

All that and 25-28mpg.

I have run it leaner but then head temps creep to 380F. I also got 31mpg!

No way 11.5 is good at idle IMHO. Just a waste of precious fuel.

agree.gif with your comments on the new fuel, but we have real gas up here. "Clear fuel", so I don't need to compensate for that.
Trekkor
13.1 here at WOT.
Trekkor
That is under load, BTW.
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