Budget M42 turbo build

[gearheadE30]

Yeah, I got it installed last weekend, but I didn't bother posting because I hadn't really gotten a chance to drive it much. It all went in great though, and the turbo really changed the character of the car, if that makes sense. Even out of boost, the throttle response feels a lot sharper. Boost doesn't come in as early (3500 versus 3000 rpm before) but it is a lot more linear and pulls hard to redline instead of dropping off around 5k. It kinda brought back the revvy nature of the M42, even if I did lose some midrange torque.

[tamtom]

re: setting up megasquirt 2 v3 on m42 e30 is

i really really need to speak to you mate,
i have spent months on months trying to search for information on megasquirting my is,
you are the only person who i know has run a megasquirt on the e30 is!
i have got to the point of installing on the car and no VR tach signal.

Any help will be very much appreciated.

i hope you have a minute to lend a bro a hand.
Thanks,
Tam.

[gearheadE30]

Wiring diagrams and other assorted files. I'm hoping they are big enough to be legible. If not, I can probably email them or specific ones to anyone in need.

[gearheadE30]

And a little update:

[Ian Bowers]

Those wheels are fucking fantastic. What do you think of the Kumhos? Whatever you do -- do not try driving them when it's (seriously) cold, they like to randomly break loose.

[gearheadE30]

haha thanks. They are probably my favorite e30 wheel, and I even have caps for them....they just need new emblems.

The kumhos are used; I got them really cheap. They are cupped a little so they aren't exactly quiet tires, but I have been pretty impressed with the dry weather grip. It's been above 55 since I put them on though. They aren't really anything special in the rain, although they aren't bad. Like you said, they can be a tad unpredictable.

[gearheadE30]

Small kinda-sorta update here. I had to put a new head gasket on the car. Apparently quarter-million-mile-old gasket material doesn't much care for boost. So I put in a new OE head gasket (I here is good for 14 psi with stock head bolts), ARP head studs, had the head machined and ultrasonically cleaned, and the valve springs were shimmed for about 30-40 lb more valve force (according to the head guy). So far, it feels a ton stronger from 6400 to 7000, where it used to drop off a bit. Soft limiter is 6700 with a hard limit at 7100 for now.

After installation, the car ran super super quiet, but had a little pressure getting into the cooling system still. then developed a I'm-going-to-fucking-explode rattle on the way to work a few days later. The upper timing rail bolt had stripped out somehow. Luckily there are a lot of spare threads back there; enough for a 5mm longer bolt. Anyone pulling that apart, I'd recommend just putting in a longer bolt now. I also re-torqued the studs. Pressure gradually went away (I think it was badly bled and some other things I have since fixed) and has been great ever since.

I also had what I thought to be an ignition knock, but retarding timing didn't help. I went back to my old NA maps and double checked a few things and found some errors resulting in about a 5 degree midrange timing advance, off boost. Result: 3 mpg increase in the city and significantly better off-boost throttle response. I can live with that.

The car still has a tendency to run a bit warm, especially on hot days. It also maybe kinda sorta is loosing a little coolant, but there is no evidence anywhere. I don't really understand though, as ambient temp shouldn't affect the thermostat or the fan switch (no engine fan, remember?). on a good day, it hovers around 195 degrees. On one of those hot days, it'll go up to 210-212. Borderline of my comfort zone, but I have no idea what to do about it.

[ROLLingKING]

wooord
lookin good

[bwawuz02]

The car still has a tendency to run a bit warm, especially on hot days. It also maybe kinda sorta is loosing a little coolant, but there is no evidence anywhere. I don't really understand though, as ambient temp shouldn't affect the thermostat or the fan switch (no engine fan, remember?). on a good day, it hovers around 195 degrees. On one of those hot days, it'll go up to 210-212. Borderline of my comfort zone, but I have no idea what to do about it.

OIL COOLER!

http://www.iemotorsport.com/bmw/E36-engine/e36oilcooladpt.html

http://www.r3vlimited.com/board/showthread.php?p=979923

Please have someone scan all your notes into PDF ftw.

Where in Indy are you again? I lived there for 13 yrs, in USAF now, posting from Germany :)

[gearheadE30]

yeah, an oil cooler would be brilliant, but unfortunately there isn't really a good place for one with the intercooler sitting up there. And the oil temp doesn't go crazy; just the coolant. I'll probably end up wiring a new circuit into the electric fan so that it runs at a low speed constantly to keep some airflow going. It's almost never on now, and that's probably responsible for a lot of the heat. I also did some retuning, and it turns out that my overly retarded ignition timing from 2k to about 2600 revs was causing a lot of it.

I'm home for break so maybe I'll find some time to get the PDFs taken care of. I have a scanner now, so it shouldn't be terrible.

I'm in Fishers, and go to school at Purdue. Germany is awesome; I did a study abroad program over there and have 7 years of german under my belt, haha.

[Lithium]

I use a fan actuator switch form an 1984 318i in my car - it comes on much earlier (I forget the exact temperature - Anyone?) & really helps.
Might be worth a try.

[gearheadE30]

Wow, I didn't know anyone was still reading this thread. I really need to update my avatar/sig too, since the car doesn't really look like that anymore...

I have a fan switch from a 318ti, which I believe is an 88C low speed/105C high speed switch or thereabouts. I've never had it come on high, and 88C is about when the tstat hits full open, so the fan doesn't cycle until the thermostat has done everything it can.

I have fixed and updated a ton of things in the last 4 years since I posted here... the high coolant temps ended up being a head gasket starting to go, so I pulled the head, had it rebuilt with shimmed valve springs for a little more seat pressure, and buttoned it all up again with ARP studs and a fresh OEM head gasket. That cured my issues, and have not had overheating problems since. I did a track weekend not too long ago, and even running 200 miles on a race track in 80ish degree weather, I had no issues with coolant temp.

Ironically, what with where this thread left off, I did get the oil temps up there. After about 15 minutes of lapping, I would actually go over 280F on the gauge, which is a little nuts. No one makes an off-the-shelf cooler solution for the M42, since it has a massive oil capacity for a small 4 cylinder and doesn't normally have oil temperature issues. I haven't quite decided what I'm going to do about that yet, other than that I absolutely need a cooler before the next track day. If my pan temps were that high, it was probably over 310F in the engine. I also destroyed the stock brakes, so I'll be putting in real brake ducts so I can try to avoid a big brake kit for the time being.

[CorvallisBMW]

For the brakes, I'd try standard Brembo blanks and PFC08 pads on all 4 corners. Lots of guys run those in LeMons/Chump enduros for 12-24hrs straight with no issues.

As for the oil cooling, is the m42 OFH the same diameter as the m30? If so: http://www.iemotorsport.com/bmw/E34-...coolercap.html

also... holy fucking threadbump batman, 4 years????

[gearheadE30]

Yeah, I had Brembo blanks and HP+ pads on there which was fine before the turbo, and before I knew how to drive all that well, but no luck now. That setup got hot enough to boil the powdercoat off my wheels, turn the wheels yellow (they were silver), bend the backing plates on the pads, and cook all the grease right out of the wheel bearings. It was great. My plan at the moment is brake ducts, Brembo blanks, and Hawk DTC70 pads since I'm a fan of their stuff. I'm sure the Performance Friction pads would work as well.

To be honest, I haven't looked into the M30. I'll do some research tomorrow and measure my housing when I get a chance, but I know the filter is different. Since that cap requires a double lip filter, I'm going to have to do some research to see if something like that exists for the M42. I know the M5X engines have a different cap that isn't compatible.

Yeah, this is an ancient thread. Like I said, I figured it had been lost in the interwebz by now, and then I got an email because of my 4 year old thread subscription, haha. I haven't even hardly been on r3v in probably 3 years...



EDIT: based on the part numbers, the M30 and the early metal-canister M42s use the same oil filter housing cap. The filters are, however, quite different with the M30 being much longer. Next step is to see if there is a filter option out there. Since there are currently no off the shelf solutions for the M42, this is definitely looks promising...

EDIT EDIT: I talked to IE and did some research on Mahle's site, among others, and with the varying dimensions of the filters, there isn't a good off the shelf solution. The guys at IE looked awhile ago for a filter, but nothing that short exists. The only solution to allow the use of that cap would be to siamese an M30 and an M42 housing, so that you can put a tall filter on the M42. In any case, the IE cap reduces the filter media volume by enough that I would be concerned about very short service intervals.

[gearheadE30]

For anyone else who finds this in the future looking for an oil cooler solution, here is how the IE cap stacks up.

Original M30B35 oil filter is a Mahle OX41D.
OD: 83mm
ID: 27.7mm top and bottom
H: 128.5mm

The IE cap uses Mahle OX154D:
OD:84mm
ID:42mm, top and bottom
H:106mm

The M42 uses Mahle OX91D:
OX91D:
OD: 82mm
ID: 28mm
H: 88mm

Based on the dimensional differences between the M30 stock vs the IE cap, the new M42 filter would need to be in the vicinity of 65mm tall.

the oil filter housing is aluminum, so this opens the door to possibly welding the M30 upper canister section to the M42 lower section, but I don't know what kind of internal differences there are without buying an M30 canister to measure. They don't appear to be available online, either. At that point, it would probably be easier to remote mount the lube filter somewhere else, or otherwise modify the base for oil diversion and takeoff to a cooler.