If you are planning to begin to premix, can you just unhook the OMP or do yo actually have to completely remove it? This would be on a 91 NA.

 

You dont HAVE to do anything to it.

But on your 91 N/A You cannot remove it without throwing the ECU into 'limp mode'

I reccomend just putting four 10mm bolts (I think) into it instead of the oil lines.

 

Someone a while back claimed the OMP eventually builds up enough pressure to drive oil past bolts. Plus, I can't imagine driving a pump with bolts in the output is good for it (not that it really matters).

What a lot of people seem to do is just remove the pump, block it off, and secure it somewhere with the electrical connection still attached. The computer sees the pump and is happy, the engine gets premix and is happy, and you don't have to worry about it suddenly deciding to **** oil all over the place.

-=Russ=-

 

This is what I did on my 91 vert. I was rebuilding the engine so I had access to everything. I am going premix.

I left the OMP alone but I removed the banjo bolts and replaced them with 4 bolts. I removed the oil lines that go from the OMP to the housing and LIM. On the housing and LIM I blocked them off with 4 bolts.
It does create pressure however it is so little that hasn't created any leaks.
The ECU is happy and I am happy.

 

On S5 (89-91) vehicles you cannot remove or "unplug" the unit from the system without it switching over into limp-mode. Unless of course you vehicle is no longer an AFM car and you don't have the factory equipment to get in the way of things.

Many just remove the unit and block off the factory provision, leave it plugged in and tuck it away in a part of the engine bay. Again, DO NOT unplug it unless you like your vehicle being inoperable.

You understand you can STILL premix while keeping the factory Metering system in place and still have the desired results you are looking for...

Regards,
-Markus

 

I've seen in other posts that you can leave the OMB in place but also add 2 stroke as a premix. The reason I would want to disconnect the OMB would be so that regular motor oil was not being fed into the combustion chambers, but rather oil that is designed to be burned. Am I missing something here?

 

Chuck...you are not missing anything. 2 cycle oil burns well and lubricates too. You don't have to worry about broken oil lines. The only down side is remembering to put pil when you fill up.

I am happy my car is happy