1987 BMW 325is going VEMS, then turbo

[[email protected]]

Sounds like you are going about things in the right way, normally its best to start rich and lean out, but as long as you're not miles out then you are not going to burn much - things can go bad quickly with a turbo...

Its a plan to keep EGO running, obviously you can't rely on it at high RPM and boost so set the off values with something sensible (75% throttle and 5K rpm) but for closed loop operation it will add reliablility and help reduce fuel consumption at part throttle and crusing speeds.

Rob

[gox]

Can i see your config or msq file?
I should try to start the car in few days,so want to be 100% shure that i dont burn anything

Expecting some dyno results from you guys.

[BenFenner]

Can i see your config or msq file?
I should try to start the car in few days,so want to be 100% shure that i dont burn anything

Expecting some dyno results from you guys.

Yah, we'll get you what you want. I figure we'll just post screen shots of our settings and you can work from there. If you want actual config files, we can arrange that as well. Look for screen caps very soon. I'm off to class though, so I'll post more later.

[gox]

Yeah,screen shots are fine,i`m not pro yet so i dont like reading config file but i`m getting used to it...

Tnx mate,did u started the car with or without turbo?

[danmartin]

The car is not boosted right now, waiting on the turbocharger to come, if it ever will. Its really not bad, just start rich and lean out where you need to. If you have larger injectors there is a stickied thread on e30tech that has some priming and cranking info that could be of use. For us we just started it right up.

[BenFenner]

Here's the lambda table I just sort of made up on a whim:



I was hoping Rob or others could comment on anything they thought might need work. The car is N/A right now, and the grey area is obviously un-tuned.
More screen caps will come. BMW 325i, you should keep an eye out for the primary trigger screen cap and others, as you'll be able to just copy us.

[[email protected]]

That lambda table looks okay but it might not be a good idea to keep 1.00 up at the boost level  I guess you're planning on that as you get on with the turbocharging.

The way VEMS calculates fuel is (in simple form)
pw = req_fuel * MAP * VE(RPM, MAP) / lambda(RPM,MAP) * gammae * ego_corr

So lambda scales the fuel according to your target lambda (and also uses its target value as a correction factor)

[gox]

Ok guys,tnx alot!

I have 55lb lowZ injectors but i will use them only on boosted engine,i have 320i 24v injectors installed they flow match our 325i stock injectors (blue ones),is it smart to put TS diode from the begining to the flyback wire so i dont need to put it later when lowZ injectors come,this can hurt right?

As far as VR,i soldered one extra the wire to shielded wire from near the sensor (benning of the shield wire) and i put it to engine ground besides oil pan,,there are some stock grounds,and i will wire other end of shielded wire to VEMS grounds,near the unit,shielded wire and yellow wire can be grounded to same point right? i will take photos of my wires setup tomorrow and post in my topic so you can view it and comment it.

I have 400Kpa bare 5v onboard map sensor (as Mattias(iXer) suggested),so in Basic Settings>Map Sensor range   i need to put 400 right? and in MapRangeUnit > 4 (>510Kpa sensor).

I did some cimping today,need to set IAT and connect sensor grounds to ground point near Genboard and i can spark and strobe the engine to get trigger wheel setings correct.

[[email protected]]

Use the TS diode.
Go for 400 kpa and 2 (High boost).

[danmartin]

These are my primary trigger settings. For the factory VR shielded wire I did no modifications. I only put the yellow (ground wire) to sensor ground and the black wire (signal) to VEMS. I didn't ground the shield  (I assumed it was already  and haven't had problems).

[danmartin]

On another note we have had an issue we have been trying to sort out, but have had little luck with. If I'm cruising along at say 3k rpm and let off throttle the car behaves as it should until around 2k rpm when the car starts to buck. For some reason it is adding fuel instead of letting the injectors be turned off.



Also we were looking at some logs of some hard shifts and wanted to know if they looked normal or if the lean out after the shift is another problem.

[[email protected]]

Looks like your overrun_fuelcut values need addressing, what values are you using?

[gox]

These are my primary trigger settings. For the factory VR shielded wire I did no modifications. I only put the yellow (ground wire) to sensor ground and the black wire (signal) to VEMS. I didn't ground the shield  (I assumed it was already  and haven't had problems).

Are you shure that Edge is Rising? I always seen Falling on M20's?

http://www.vems.hu/wiki/index.php?page=MembersPage%2FMattiasSandgren%2FPeppesBmw

Maybe i`m wrong but....

[danmartin]

"When using a VR sensor the ECU must be configured to trigger on the rising edge of a tooth."

I read this http://www.vems.hu/manual/html/ch09.html#Detailed.Sensor.RPM.Config

My signal is great so I guess I must be doing something right.

[BenFenner]

Dan, looks like your overrun_fuelcut values need addressing. You should get on that.