aem infinity standalone on e36 obd 1

[bry195]

that "newVE" function works great. log a run and it tells you what to set the VE to.

[bry195]

here we go. no more wire nuts.


so how does this work? the oem pressure regulator still manages fuel pressure if the pump is not overpowering it. so you turn the knob (variable resistor) and the pwm to the motor allows you to dial it in. the interesting thing is that after 20 minutes of driving you may lose 10 psi of running pressure. Im not sure if this is from the pump or fuel warming up or if BMW compensates afr for temperature. so if you adjust pressure up to just before you overrun the reg with the car hot and let the car sit overnight, pressure will be high the next day until it warms back up.

its all pretty interesting but I will solve it with a temp compensation.

to be fair, I have not boosted more than a couple psi yet so more info to come.


what I suspect: a pwm drive limits current (you can adjust). this applies to brushless pumps, boost a pumps, or brushed pumps.

current is how we generate pressure. as the rotor warms up the relationship is skewed by temperature. the current to pressure relationship stays the same except the hole relationship is shifted up or down based on rotor and winding temperature. the rotor dissipates heat less than the stator because it has less surface area and only 2 connection points to the housing.

[bry195]

I learned something. if the IACV does not close during boost the car acts like the plug gap is off above 3000 rpm and a couple psi. even if lambda and timing is right. interesting. so at 2k pwm the valve closed (2/3) duty.

[bry195]

I love VE tuning. I went from running the car up to atmospheric pressure to 12 psi in 15 minutes.

1-got it to idle at 14.6 to 14.8.
2-PID for IACV position seems to change. if I set it with the car full hot I get a 25 rpm oscillation when its full cold and vice versa.
3-set oil pressure and afr failsafes (at full hot) and found that pressure doesnt respond as quick in relation to RPM with different loads. had to use numbers wrapped around unloaded values. Makes sense just something that I learned during application.
4-wheel speed sensors dont synch until 11MPH. should be able to lower the filters in the infinity and get better low speed synch.
5-If I set the fuel pump at about 2/3 duty I see 64 psi at idle ad 44 at 12 psi of boost. I would like to set it at 50 and have it stay there.
6-AC works, just cant bring myself to use another input to shut it off.

[bry195]

almost completely cleaned up. its hard to believe all that crap fit in there.

Ok,
Here are my feelings on the AEM infinity
the programming, logging, hardware, and calibrations are top notch, wicked fast, failsafes up the a$$. Every function you can imagine is built in. im on 100lb injectors and the car idles more stable that the OEM DME and AFR is more stable at cruise. Fuel tuning is almost not required and its 5 minutes of work when you do it.

Knock monitoring is built in and loggable.
ignition tuning---well im using someone elses for now but I have pushed a few numbers around.
everything is fairly easy.
I wired the whole car and all the sensors at one time. I would suggest getting power, cam/crank, and injectors going before going further, and make it right.
this is not a plug and play. you do need some electrical understanding.
Maybe I'll make some plug and play harnesses but only for a trade.

the car feels stronger, more responsive. it feels OEM but the install is not for a beginner.

[bry195]

Well if you found this thread then you probably feel this was a complicated install. It wasnt, I overcomplicated it because this is what I do for fun. The hardware, support, and software are second to none. I had a little support here and there but for the most part I did this on my own. Yes I do this type of thing for a living so its sounds like Im talking a different language sometimes. I did the thread for me. Feel free to ask questions. Kevin325 (iirc) did a much better job of keeping things simple. He is a nice guy, reach out to him. Boris runs an AEM. DEF runs an AEM.

Look at infinity tuner. Its free. Select a layout. Then select a base session and you can simulate an obd1 m3.
AEM Data is free as well. Best logging software I have seen.
The support at AEM is top notch. Call them and ask questions.

[bry195]

[IMG][/IMG]

[murad5058916]

here is the idle invert circuit.

the bmw idle control valve (iacv, icv) is a 3 pin. aem can only manage a 2 pin so here is an adaption board. the drawing is in the AEM e36 m3 application manual.

I have aem infinity in my s52 I can install the 2 wire idle motor from the old m50b20