Motronic MAP sensor conversion

[sleepy350]

Hi I've been looking at options for converting to MAP and really haven't found anything that doesn't involve switching to standalone. I want to do this and have it running properly before I install my turbo setup. So far all I can think of is using a UAFC from 14point7.com (http://14point7.com/UAFC.php), basically replace the MAF completely and use a Motorola MPX4250AP. The reference signal is 0.2v to 4.9v, and I would use the UAFC to correct the voltage and in turn the AFR. Anybody have any thoughts on this setup? This is my first time really messing with fuel injection things (learned about cars working on my fathers carburated muscle cars,) so please excuse me if I have this ALL wrong.

Kind of like this:


Thanks in advance, Angelo.

[E30-323ti]

have you looked at the MAP2ECU...

http://www.mapecu.com/

[nando]

E30's are actually a good canidate for MAP sensors because the AFM works on a similar principle (speed/density). They do not have a "MAF". You could do it with something like tunerpro/ostrich, but it's going to require a bit of R&D and hacking on your end.

[sleepy350]

E30's are actually a good canidate for MAP sensors because the AFM works on a similar principle (speed/density). They do not have a "MAF". You could do it with something like tunerpro/ostrich, but it's going to require a bit of R&D and hacking on your end.

I am actually planning to use an ostrich for timing adjustments. Would I be able to take the signal from the map directly to the ecu and use tuner pro to compensate for voltage change?

[sleepy350]

have you looked at the MAP2ECU...

http://www.mapecu.com/

Intriguing but for $400+ I would opt for MS...

[einstein57]

Interesting idea but once you add the cost of the ostrich you'll be in megasquirt prices but with out data logging, wideband capability, launch control, boost control, wasted spark, knock control, etc. Megasquirt is gods gift to the shoe string budget tuner like myself. That map ecu looks ok but all those add onts cost an arm and a leg.

[sleepy350]

Interesting idea but once you add the cost of the ostrich you'll be in megasquirt prices but with out data logging, wideband capability, launch control, boost control, wasted spark, knock control, etc. Megasquirt is gods gift to the shoe string budget tuner like myself. That map ecu looks ok but all those add onts cost an arm and a leg.

I'm actually picking up an ostrich from my co-worker for super cheap... But eventually forsure I'm going to end up with MS or similar.

In total for this whole setup I'm looking at a total of 200-250 including the MAP sensor just to get it running. Ill deal with bigger injectors and a rrfpr later.

So what I have for my turbo engine management is: a MAP sensor, a UAFC to translate the signal, an ostrich for timing adjustments and for helping compensate for the different voltage output from the MAP, eventually bigger injectors and a rrfpr.

What do you guys think? Ive estimated the total including everything, I'm looking at around 400 if I can find some cheap injectors and a cheap rrfpr.

[Syncro325is]

I'm actually picking up an ostrich from my co-worker for super cheap... But eventually forsure I'm going to end up with MS or similar.

In total for this whole setup I'm looking at a total of 200-250 including the MAP sensor just to get it running. Ill deal with bigger injectors and a rrfpr later.

So what I have for my turbo engine management is: a MAP sensor, a UAFC to translate the signal, an ostrich for timing adjustments and for helping compensate for the different voltage output from the MAP, eventually bigger injectors and a rrfpr.

What do you guys think? Ive estimated the total including everything, I'm looking at around 400 if I can find some cheap injectors and a cheap rrfpr.

Why a RRFPR? You can tune the fuel maps on motronic with tunerpro and the emulator.

[sleepy350]

Why a RRFPR? You can tune the fuel maps on motronic with tunerpro and the emulator.

If I edit the fuel maps I wouldn't need to raise fuel pressure? or would I just have to use a regular old adjustable FPR?

[Syncro325is]

Not until your system can't provide enough fuel. Then update the FPR, But I would just get a stronger pump.

[sleepy350]

Not until your system can't provide enough fuel. Then update the FPR, But I would just get a stronger pump.

Hmm, so your saying go with the stock FPR, and upgrade the fuel pump, tune from there and if the FPR isn't providing enough pressure, only at that point should I replace it. Makes sense, anybody know how many psi stock M20B25 fuel rail pressure is? Just for reference..

[whodwho]

3 bar = 43.5113213 pounds per square inch

[nando]

I am actually planning to use an ostrich for timing adjustments. Would I be able to take the signal from the map directly to the ecu and use tuner pro to compensate for voltage change?

yes, that's how I would do it. you need to figure out how to do it, but I'd avoid using any signal "translators". Map sensors can be noisy on M20s as it is, without adding an additional step between the sensor and ECU.

[sleepy350]

3 bar = 43.5113213 pounds per square inch

Thanks.

yes, that's how I would do it. you need to figure out how to do it, but I'd avoid using any signal "translators". Map sensors can be noisy on M20s as it is, without adding an additional step between the sensor and ECU.

May I ask what you mean by "noisy?"

[nando]

the pressure waves in the intake manifold - at peak torque where the pulses are strongest, the MAP sensor picks these up and you see it as the pressure rising/falling dramatically within a short period of time. When the average pressure is much closer to atmospheric (assuming WOT).