Late M44 in an E30.

[D. Clay]

Has anyone put a 1996-2000 M44 in an E30? Can you use the M42 intake, fuel injection, and electronics like the 92-95 models. I know the crank sensor for the late M44 is on the back of the crank in the block but the cam sensor is in the same place.

[sheepdog]

I have heard now that the crank sensor is incompatible, but I have also heard that it is compatible with the e30 computer. Not sure.

I do know you need the dual sensor temp sensor if you want an easy conversion, otherwise most parts swap rather easily.

[strypt]

The crank sensor work with M42 ecu but the cam sensor doesn't. M44 uses a hall type sensor and M42 uses VR.

[D. Clay]

What is the solution? Can you swap sensors? Cam gears? What is the difference between Hall and VR? This aspect of tuning is all new to me. They appear to be in the same place per realoem but they re-use a lot of images and they are not necessarily accurate.

[D. Clay]

I asked locally and the consensus seems to be one of two ways. To go with the M44 electronics the same as with an M50, etc and also deal with OBDII or use M42 cam gears. This can be problematic because the front of the M42 motor is usually the cause of the need for a swap and the wear problem if the gears and chain are to severely mis-matched.  An old short track racer friend suggested drilling the M44 sprockets to accept the M42 trigger. The M44 uses a notched plate (#5) - and the M42 has a pin in the gear ( may be magnetic). The upper front covers may also need to be swapped if the openings for the sensor  don't line up. No one seems to have actually done this swap (please speak up). Pics are attached- M42 on left and M44 on right.
 

[Royalratch]

I've done this swap with my local garage and it works fine but there are a few things to accommodate.

1) You can keep the M44 loom/wiring but you'll need to figure out the EWS/OBD security stuff - as mentioned above. So that means the making the E36/M44 key barrel etc.

Or just use the M42 electronics and re-map to suit the 1900cc.

2) The DISA stuff can also be a PITA. I just used the M42 inlet manifold, AFM and coilpack etc. Only had to change one pulley I think.

3) The M44 has 1 temp sensor that feeds to 2 item (the ECU and Temp Guage). The M42 uses 2 separate sensors for this. Still trying to get the M44 sensor to play ball with my temp gauge as I didn't want to bodge it by plugging a second sensor into the thermostat housing.

[strypt]

I use the complete M42 wiring and ECU, you can just put the M42 VR sensor in the M44 front cam cover but then you'll need to put some kind of spacer in between as the VR sensor is deeper. You also should change the cam gears as the M44 trigger is completely different (as you can see on the pics). I haven't done this and I don't know for 100% that the M42 cam gears fit, but my car runs fine with the wrong trigger anyway I bet you could even skip the cam sensor, as the engine appears to run well with the sensor unplugged. But I only unplugged it and revved the engine a couple of time so I'm not sure how the engine runs under load.
I know my "solution" isn't the best but it works and I wouldn't have done it if I didn't have a Autronic SM4 ecu ready to be installed within a month or two

[sheepdog]

The cam sensor is technically a backup to the crank sensor. Does it need it, hard to say.

[tim_s]

The cam sensor is technically a backup to the crank sensor. Does it need it, hard to say.

no, this is incorrect. The cam sensor tells the ECU whether it's an intake or exhaust stroke - for sequential ignition/injection it is required.

[Cristian G in Oz]

no, this is incorrect. The cam sensor tells the ECU whether it's an intake or exhaust stroke - for sequential ignition/injection it is required.

The easy way to describe it is that the crank sensor tells the ECU how fast the engine is going.  The Cam Sensor tells the ECU when the engine is opening the valves that it is reading off. As Tims S said, essential for sequential injection.
When you through a Crank angle sensor into the mix it tells the ECU where the engine is in the cycle.  
The ECU compares the Crank position, Cam Position and then Crank speed to say throw fuel here and spark here.

Cristian

[strypt]

The crank sensor (on the M42) not only tells the ECU the rpm, but also the position of the crank so it knows when it's at TDC. The cam sensor then determines if it is cyl 1 or 4 that is in the right stroke for a spark. Then by the firing sequence it knows which cyl to fire next etc.
If the sensor fails it will go into wasted spark 'mode', firing plugs 2 and 2. And since the crank sensor will tell the ECU wheater the engine is at TDC or not it will still work. But it's not an seq. ingnition anymore

[sheepdog]

WTF?
Who the hell thought up that system? Oh wait, this is a German car, of course it is over engineered.

[Royalratch]

I'll share a proper more tech breakdown of what happened with mine in a couple more days. Just having some cosmetic stuff done and then it will be finished!

[DaveM-sport]

I'd be interested in the work needed to drop the M44 into the E30 too.

I can get a reconditioned 99 M44 out of a friends crashed iS.
Wonder which would be better for an everyday car in an E30

M42 or M44. Would it be faster than what  have now (Remapped M42) or better on fuel???

[KidneyBoy]

Im looking  into doing this also.

Found a '95 M44 with 52k for $200. Its a short block, so i would be using most of the E30's running gear [wiring included]

Has anyone used the M42 ECU on the M44? I was hoping i could get away with this.