noob question about vanos

[ieatpeople]

i have a 92 325i 5spd. it has a non-vanos m50 in it with low compression in one cylinder (cyl 5 has 120psi). once this engine dies (whenever that is), i will need to swap something else in.


instead of searching for another nv m50 to put in, can i just get one with vanos? will it run with the ecu for the nv motor?

i read a few threads that seem to indicate that the vanos simply will not function, but the motor will run fine.

[frankie591]

if you get an m50tu, why would you not want the vanos to function? If you are getting a motor, the ecu should come with it anyway so just swap the ecu.

[ieatpeople]

like i said, i'm a noob with the m50 motors. i'm familiar with m20's....


basically, i'm looking for the easiest way to get another running engine to swap in, preferably one that doesn't involve any wiring changes.

if all i have to do is swap the ecu, and no wiring, i can do that.

[frankie591]

pretty sure you need a tu harness to run the tu motor. If you dont want to reqire, I'd look around and find another m50nv that you can direct swap.

[FredK]

No, the motor will not run fine, as the gap in the teeth on the front timing wheel / harmonic balancer assembly is different between the M50TU and M50. You will have to swap out the harmonic balancer. I am 99% certain either or both the crank or cam position sensor will need to be brought over from the NV.

You can't just swap the ECU, either. You need a TU harness to run a TU engine.

The wiring is not rocket science. There is no difference between the TU and NV pinout to the C101.

[ieatpeople]

if i dont have to cut & splice, i would be interested in swapping in a tu motor, they are much easier to find...

[ieatpeople]

No, the motor will not run fine, as the gap in the teeth on the front timing wheel / harmonic balancer assembly is different between the M50TU and M50. You will have to swap out the harmonic balancer. I am 99% certain either or both the crank or cam position sensor will need to be brought over from the NV.

You can't just swap the ECU, either. You need a TU harness to run a TU engine.

The wiring is not rocket science. There is no difference between the TU and NV pinout to the C101.

so, if i swap the harmonic balancer, and possibly the cam and crank sensor, i can run a tu with an nv harness and ecu? just no vanos function?

[FredK]

I'm not 100% sure if you can just not feed any oil to the VANOS and have it not fall apart and throw metal shavings into your head. I guess if you can somehow attach the VANOS oil line that it would probably work.

But, wiring the engine takes around 20 minutes if you use butt splices. I'm not sure why you're so averse to wiring. If you need a walk through, just post a thread, we'll walk you through.

[slammin.e28]

If you buy a vanos motor, you want the vanos to work. Period. I just rebuilt the vanos on my S50 and it's a night and day difference.

[ieatpeople]

ok, for now i'm just gonna stick with the current m50nv. it had a wicked misfire, but i changed the plugs and the valve cover gasket (had oil in the plug holes), and now it runs pretty damn good. still has a very slight hiccup sometimes, i think i need to clean the maf.

i know there are alot of people in my area that would be willing to help with the wiring if i do a swap, until then, thanks for answering my stupid questions!!