Trying to lean out the engine....

[F1Rocks]

1988 engine, early car but have the late DME, late AFM, late injectors etc...

New engine, 4 race hours on the engine, broke it in on a dyno,

I am NOT using an O2 sensor and the wiring for it is long gone.

I'm reading 11.3 on the wideband at WOT in third and fourth gear and about 12.5 at idle

Fuel pressure is steady at 29psi through the entire range.

What is the best way to lean this back out?

Thanks
Brent

[v2rocket_aka944]

FQS switch will pull a little bit. I know some have put a resistor in the coolant sender wire to make DME run richer, could go the other way somehow. Smaller injectors (19lb), lower FP...why delete O2?

[F1Rocks]

Wiring for the O2 sensor was non existent when I aquired the car.

Running no cat and straight pipe so never bothered to try and add it back in. Assumed the DME with lack of signal would simply run at start up level all the time.

I've been told that the AFM can be adjusted to help with this, anyone have a write up on the procedure?

[krystar]

if u open the AFM cover, you'll see the toothed big wheel, and the spring is latched at one of the teeth. move the spring so it's latched onto a different tooth.

iirc, 1 tooth clockwise is -1point AFR. don't quote me on that. better try it out with a wideband hooked up.

[guru944]

F1Rocks;

I would wire an O2 sensor back in the DME/Harness. Bosch DME need it signal to monitor A/F ratio, especially after warm up/close loop operation.

Easy install...
Later