M50 non vanos OBDII conversion

[et89]

So, I'am working on something different now, this will involve an M50NV with a turbo.
for tuning purposes we would like to convert this to OBDII.

I know about the things that I need to convert but I am worried about one thing:
is the non vanos head compatible with OBDII when i change the camshaft sensor to an OBDII sensor?

For the rest I have:
-OBDII wiring loom
-camshaft position sensor
-crank position sensor
-M52 coolant temp sensor
-M52 knock sensor
-M52 intake air temp sensor
-M52 trigger wheel or change the M50 trigger wheel.

[bluptgm3]

The OBDII crank position sensor is in the block just above the starter, measuring a segmented wheel on the crank.
The OBDI crank position sensor is in the front timing cover, measuring the trigger wheel on the harmonic balancer, much larger diameter than OBDII crank trigger wheel.
I believe the NV engine also measures the HB trigger wheel.
I am assuming -
Both the OBDI trigger wheel and the NV trigger wheels are of a larger diameter than the OBDII crank based trigger wheel and as result generates a different pulse than what the OBDII ECU anticipates.


Sent from my iPhone using Tapatalk

[et89]

The OBDII crank position sensor is in the block just above the starter, measuring a segmented wheel on the crank.
The OBDI crank position sensor is in the front timing cover, measuring the trigger wheel on the harmonic balancer.
I believe the NV engine also measures the HB trigger wheel.
I am assuming -
Both the OBDI trigger wheel and the NV trigger wheels are of a larger diameter than the OBDII crank based trigger wheel and as result generates a different pulse than what the OBDII ECU anticipates.


Sent from my iPhone using Tapatalk

The EURO OBDII crank position sensor is also using the harmonic balancer an the front timing cover, and indeed the NV engine does so too.
Using the EURO crank sensor fixes this problem for the OBDII swap.

My question is about the CAMshaft position sensor and if/or the camshaft trigger for the M50NV is the same as for the M50TU and M52.
I do think so, but I am not completely sure.

[bluptgm3]

Check p/n in www.realoem.com for both engines.

Do the Euro and US OBDII engine variants share the same ECU?


Sent from my iPhone using Tapatalk

[someguy2800]

You can use the euro front mount crank posistion sensor on an M50 block with the US OBD2 ecu.

Also the trigger wheel on the cam is very much different on the non vanos cam so you will need to put a vanos cam in the intake side of the head and use an OBD2 cam position sensor. You can still lock the intake cam and run the non vanos front cover and valve cover if you so feel like it.

One more thing the OBD2 ecu is going to expect to see the intake cam move when it commands the vanos solenoid on so that will need to be dealt with by whoever is tuning the ecu.

[et89]

Check p/n in www.realoem.com for both engines.

Do the Euro and US OBDII engine variants share the same ECU?


Sent from my iPhone using Tapatalk

I am confident about everything ECU related, the only thing I am not confident about is the camshaft trigger from camshaft to euro camshaft position sensor. Someguy answered that question for me though. thanks for the input!

You can use the euro front mount crank posistion sensor on an M50 block with the US OBD2 ecu.

Also the trigger wheel on the cam is very much different on the non vanos cam so you will need to put a vanos cam in the intake side of the head and use an OBD2 cam position sensor. You can still lock the intake cam and run the non vanos front cover and valve cover if you so feel like it.

One more thing the OBD2 ecu is going to expect to see the intake cam move when it commands the vanos solenoid on so that will need to be dealt with by whoever is tuning the ecu.

Thanks a lot! very usefull info! I assume M50TU or M52 camshaft will be ok?

I can eliminate the vanos solenoid with tuning the OBDII ECU. that is the main reason to go OBDII.

[someguy2800]

I am confident about everything ECU related, the only thing I am not confident about is the camshaft trigger from camshaft to euro camshaft position sensor. Someguy answered that question for me though. thanks for the input!



Thanks a lot! very usefull info! I assume M50TU or M52 camshaft will be ok?

I can eliminate the vanos solenoid with tuning the OBDII ECU. that is the main reason to go OBDII.

I know very little about factory ecu's but the two things I wonder is with an OBD1 ecu can you just raise the vanos set point to an artificially high number like 9000 rpms or something? The 2nd question is why don't you want vanos? Is this a race car or street car?

[et89]

I know very little about factory ecu's but the two things I wonder is with an OBD1 ecu can you just raise the vanos set point to an artificially high number like 9000 rpms or something? The 2nd question is why don't you want vanos? Is this a race car or street car?

I do not know about the OBDI ECU, but the OBDII ECU you can change the control bits to switch off VANOS permenantly. I can also set the RPM to when I want vanos "to kick in", which is acctually vanos turning off, for high load situations,
and there is a RPM-engine load controlled map for low load situations. if you want to be sure you can set the control bit and rais these paramenters to a tresshold that you will never reach.

I use the control bit and that works perfect.

Why no vanos, We want to get the thing running with what we have now.
Will an M52 or M50TU head be a straight fit to the M50NV?

[E30s50dude]

I recently did this conversion on my own set up hope this helps https://www.bimmerforums.com/forum/s...t-crank-sensor

I can also send you front crank PN when i'm home I did ordered from a UK site with the help of my brother who is stationed overseas.

[et89]

I recently did this conversion on my own set up hope this helps https://www.bimmerforums.com/forum/s...t-crank-sensor

I can also send you front crank PN when i'm home I did ordered from a UK site with the help of my brother who is stationed overseas.

Thanks, but my question is about the camshaft pos. sensor. I have alle the parts that I need, I was just wondering if I could use the EU CAMshaft sensor on a NON VANOS m50 intake cam.
Someguy answered this question for me, i need either an vanos Head, or a vanos intake cam.

[someguy2800]

You can use either head casting. The little timing wheel on the front of the cam is what is different. The non vanos one uses a single narrow tooth and a VR cam sensor. The vanos motors use a wide 180 degree blade for the sensor to read. You can't put the vanos pickup wheel from the vanos motors on the non vanos cam. There is no difference between a euro and US cam sensor.

[et89]

You can use either head casting. The little timing wheel on the front of the cam is what is different. The non vanos one uses a single narrow tooth and a VR cam sensor. The vanos motors use a wide 180 degree blade for the sensor to read. You can't put the vanos pickup wheel from the vanos motors on the non vanos cam. There is no difference between a euro and US cam sensor.

I just checked a picture of non vanos and vanos cams and i understand what you mean.

but to be sure:
-I can use both an M50TU or M52 intake camshaft in the Non VANOS head?
-If we would like to use VANOS on this, I can use either an M50TU head or an M52 head on the M50NV bottom end?

thanks for your replies!

EDIT:ok, I should have used the search function before asking these questions. won't be the first to do this.

[someguy2800]

Yes you can use either head on M50NV bottom end. You can add vanos to the M50NV head by grinding a little bit of material off the front of the head and putting the cams and sprockets from a vanos head on it. It all bolts right up once you clearance the front of the head. Yes you can use an M50tu or M52 cam. This will be a downgrade in performance unless you use vanos since they have less lift and duration than the non vanos cam.

What I would recomend you do if you don't want to use the vanos is to put the non vanos intake cam in the exhaust side of the head and get an M54B30 intake cam for the intake. You can run a vanos cam without the vanos actuator if you just replace the studs on the front of the cam with bolts to effectively lock the intake cam. If you want to do that I sell timing tools to properly time the cams. I used to run this setup in my car running in the high 9's.

[et89]

Yes you can use either head on M50NV bottom end. You can add vanos to the M50NV head by grinding a little bit of material off the front of the head and putting the cams and sprockets from a vanos head on it. It all bolts right up once you clearance the front of the head. Yes you can use an M50tu or M52 cam. This will be a downgrade in performance unless you use vanos since they have less lift and duration than the non vanos cam.

What I would recomend you do if you don't want to use the vanos is to put the non vanos intake cam in the exhaust side of the head and get an M54B30 intake cam for the intake. You can run a vanos cam without the vanos actuator if you just replace the studs on the front of the cam with bolts to effectively lock the intake cam. If you want to do that I sell timing tools to properly time the cams. I used to run this setup in my car running in the high 9's.

I have sent you a DM.

[hobbit382]

Use this for NV intake cam on obdII

11 31 1 730 506

[et89]

can I put that on the M50NV intake cam? and run it with MS41.2.