My M52TU Swap

[accident]

awesome thread! i would love to put this motor in my 98 328is

[hoveringuy]

a buddy of mine has a TU motor in his e30 racecar. With the Pete M headwork and a few other things, he's pushing close to 240 at the wheels. Its OBDI though

You say OBD1 like it's a bad thing. It's running 240 because it's OBD1!

[Lawson509]

I am not meaning to bag on OBDI swaps. I realize they put out more hp than doing what I am doing. I actually was contemplating that fact at the beginning. A guy who graduated from my university two years ago did an OBDI m50 swap. I really didn't want to copy him when figuring out what to do for my graduating senior project, so OBDII seemed logical. Plus i got an entire e46 car with all the matching components for cheap. OBDI is not bad at all, especially when it comes to power. The downside to OBDII for me is that getting extra power will be really spendy.

As far as the question to the swapping out suspension, as far as I can tell, the rings on the axles have the same amount of teeth on them. I could be wrong on this issue, but I will continue looking into it.

[Jand3rson]

Could I get some info on that 944 brake booster/master stuff?

[Lawson509]

as far as what year, I am not completely sure. Mine came out of an 84 2.5L, but as for the master, the piston diameters are the same front and rear. the stroke is slightly shorter on the 944 though. The ports are really close to the same spots as on the 325's, but they are a little closer together and angled slightly up.

[Lawson509]

Continuing the project... So I finally took my car down and pressure washed and cleaned my engine bay. Got everything ready for test installing the motor. It was commented early on that the stock M52TU headers were heavy and restrictive. This is very true, and I had intended to use them, or at least for the moment. However, the stock headers are really flat and stick out almost 6" from the engine head. I tried a test install of the motor during thankgiving break and found that this was a problem. The stock headers ended up hitting the frame rail and I couldn't use them. They also hit the eyelet of the control arm and the e36 motor mount arm. So I turned to the e36 m3 headers. The new headers fit nicely and will give better flow. I used high temp paint and painted them black to match the general color them in the bay.

[Lawson509]

Went ahead with the install of the motor. This is only a test fit, cuz it has to come back out to shave the oil pan and to put the snap ring in for the oil pressure regulator on the oil pump which I so handily lost during my motor rebuild. Currently The motor sits in the car and I have been trying to figure out placement of the secondary air pump. I will have to move over the windshield wiper fluid tank due to it rubbing against the engine. I will also have to move the heater core out put lines. I pulled the dash out so I can start work on rerouting my wiring harness.

[hoveringuy]

Supposedly the M54 and M52TU headers are port-matched to the M50. The OBD2 headers rock and I actually didn't gain top-end power when I went to headers, I gained mostly low-end torque.

What are you doing for the e30 temp sensor?

My lower radiator hose didn't fit exactly right. The thermostat inlet is in a slightly different place from the M50, and the radiator outlet is about 3" away from where it is on the 330.

[Lawson509]

Well actually since I am using most of the wiring from the e46 including instrument cluster, I will be using the e46 temp sensor. I saw the billet aluminum piece you had with the e30 sensor adapted to it, but I won't need to do that since I am using the newer instrument cluster and DME.

[hoveringuy]

Oh yeah... good point!

[Lawson509]

Hey so I absolutely hate the stock seats from the sedan. They are not bucket seats in the slightest so I went with some procar seats from scat. Met the guys from scat at the las vegas sema show and they hooked me up with a really good deal. From my donor car I do have a pair of black vinyl bucket seats if anyone is interested. They are a little torn on the bolsters but other than that they are ok.

[Lawson509]

So I decided to use the e46 steering column with its steering wheel since it has a little nicer setup than the e30s setup. I had to make custom mounting brackets for it, but I did this a while ago in my other junk e30. I got the new column and wheel in my car last night. The wheel itself is a bit rough, but I will get a new one when I have the money. Anyway here it is:

[Lawson509]

Started

Hey so Thought I would post a little bit of an update. I finally got everything hooked up and wires all soldered up and cut out tons of wires. I have spent countless hours working on this through the last couple weeks. I had trouble getting my CAN busses to communicate, but I finally got things to work out and have focused on wiring in all the extra sensors.

The lack of sensors being hooked up has been throwing codes at me through the DME, but I have nailed most of those down and fixed them except for CAN bus error to the EGS, Fuel tank sensor codes, and purge system codes. The purge codes, I haven't decided how to tackle those. I might add a purge tank system in later, It wouldn't be too hard. The EGS code I am having a BMW service rep to get me the letter coding to flash the Tranny out of the system so it won't look for it anymore. The fuel tank sensor codes are being a bitch. The e46 fuel level sensor operates on a full/empty Ohm reading of 250/10. The e30 uses a full/empty of 5/70. So they are complete opposites in reading styles of resistance and voltage levels. I have been playing around with the idea of making a small circuit board using an opamp to flip the signal from a 0v-12v reading to 12v-0v. We'll see how that works.

Other than that the motor barked to life really quick. I will post photos of overall progress later. I had to customize and fabricate a sensor mount out of aluminum to get the e46 radiator outlet coolant temp sensor into the system. I welded it up and then a buddy and I worked on machining it so the sensor would click right in and seal.

The new sensor and mounted



Here's a new PS high pressure hose I had a hydraulics shop make. Works awesome.

[accident]

holy shit!

[Lawson509]

Yeah my next big leap to get done is wiring in all the lights and body electronics into the system. Because the OBDII system uses the LCM (light control module) as a back up location for data filing with the instrument cluster and DME I have to use it and adapt it into my wiring harness. I also have to attach bits and pieces to the e46 body control module to get things reading right.