Yet another M30 E30 amongst your ranks. WHATS THE DIFFERENCE BETWEEN A PORCUPINE AND

[Adiabatic]

Hey all!

I just acquired an M30 E30 about 95% through the project from one of your forum members.

Saving this space for some pictures to come.

Incredibly fun problems:
Head bolts torqued incorrectly, causing exhaust gas in coolant, causing minor overheating (45 ft-lbs?!?! Who thought that was a good idea?)- Fixed
Thermostat in backwards, causing minor overheating - Fixed
Heater core plugged, causing drastic and rapid overheating - Bypassed, new one ordered
Sexy new owner, causing drastic and rapid overheating - Can't figure this one out.
Running pig rich, fouling plugs out - New concentration!
Seat belts (or lack thereof) - Ordered
Tach/Speedo inoperable ("new" cluster too) - Haven't even started on this one.
Bunch of interior crap to be resolved - To be resolved

So far it's been quite a fun time waster. I love diagnosing problems and it hasn't let me down in that regard. The coolant system in these cars is a trip, and who knew a heater core could be so easy to replace! I've also named it Oliver, a la Top Gear.

It's probably due to the rich condition, but it seems like there should be a lot better acceleration from this car. Anyone have the HP/TQ rating for the M30B35, and some 1320 approximations for one descended from the heavens into yonder 3 series? Body is a '91 318i. I don't have the year on the engine (late 80s? It's Motronic 1.0, reads off the flywheel), but will later in the week.

[wildstoats]

Hey all!

It's probably due to the rich condition, but it seems like there should be a lot better acceleration from this car. Anyone have the HP/TQ rating for the M30B35, and some 1320 approximations for one descended from the heavens into yonder 3 series? Body is a '91 318i. I don't have the year on the engine (late 80s? It's Motronic 1.0, reads off the flywheel), but will later in the week.

Sounds like a fun project. Very close to my build actually. First off I'm not sure what engine you actually have. You said B35 but if it's Motronic 1.0 and has the flywheel sensors then it is probably a B34. Does it have a toothed wheel on the crank pulley? Does the intake manifold say 3.2/3.4 or just 3.5?

Here is a sample dyno graph for you:


That was my car on a Mustang dyno. Well technically it was my e28 but that's pretty typical of an M30B34. I think I had some "jitter" due to some electrical issues I was having but other than that it's a low mileage good condition engine. The B35 would be slightly higher than that. I'm not big on drag racing so I can't help you too much in that department. What differential ratio are you running? My e28 always felt kind of sluggish (granted it is a heavier car) but I always attributed that to the S3.25. If you went for a shorter gear ratio that would surely help the cause. I know S3.73's are popular with some of the guys and the 3.46 / 3.64 are rare but a nice compromise between the 3.25 and the 3.73. I'm going to try out the S3.25 from my e28 because I had it laying around.

Oh and pictures ... now :hitler: haha

P.S. Lots more graphs here if you are interested: Mye28 Dyno Graphs

[chadthestampede]

Sexy new owner, causing drastic and rapid overheating - Can't figure this one out.

I had the exact same problem when I bought my car.

[John1180]

Tach problems sounds like a dead battery on the S board.

[Adiabatic]

Does it have a toothed wheel on the crank pulley? Does the intake manifold say 3.2/3.4 or just 3.5?

Unfortunately I'm currently an hour and a half from the car and will be until Friday. I'll be sure to let you know once I resume work on Oliver to make him less Oliver-ish.

Oh and pictures ... now :hitler: haha

See above, though if I can find the cache of the sale thread on this forum that will hopefully hold you over :)

Also thanks for the numbers. I've got an "upgraded fag Miata" S2000 (yes, I've actually heard that from someone at an event) if that tells you how much I'm into drag racing... I just wanted some input on the acceleration characteristics aside from the SOTP Meter.

[Adiabatic]

Tach problems sounds like a dead battery on the S board.

I'll be sure to check that when I decide to tackle the heater core, but the weird thing is both speedo and tach failcheck on startup... Nothing on KOEO but I'm pretty sure it shouldn't anyways.

I forsee a lot of backprobing in the near future.

[Jean]

Welcome

[Adiabatic]

You said B35 but if it's Motronic 1.0 and has the flywheel sensors then it is probably a B34. Does it have a toothed wheel on the crank pulley? Does the intake manifold say 3.2/3.4 or just 3.5?

The intake manifold doesn't say anything, but the side of the block says "3,5" which is crazy german talk for 3.5...

Still no pics, but definitely middle of this week I promise. I've been working on it today and found out some GREAT things the previous guy did.

Things the PO fucked up:

Head bolts torqued to 45 ft-lbs instead of 75.
Thermostat in backwards
Steering wheel not spaced correctly, nut not torqued down at all
various shitty vacuum leaks
plugs incorrectly gapped

Plus a whole measure of fucked up wiring. Still working on all the vacuum leaks and diagnosing the inop tach/speedo. I'm getting switching from the sensors @ the flywheel.

Also, to figure out exactly what engine this is, I got these numbers from the side of the block:

|...........................23086............ 287639.... |

in that spacing-ish

[RickSloan]

is this a white 4 door???

by the sounds of things it is.

and the tach is prob a wiring issue, esp if its b34 with and m30 harness. Mine bounces after shut off but doesn not work at all. Never looked into it yet.

Awesome project tho man, hopefully we can be alot of help, awaiting pics!

[LowR3V'in]

Does your engine have this type of manifold? :(
Since you say it doesn't have a 3.x on it.

[Adiabatic]

Nope, it's not an M90 I don't think. The PO said he painted the intake manifold, which is a regular M30 manifold aside from not having any displacement designation on it. The block definitely says "3,5" in big letters on the drivers side, however.

No luck on the numbers I posted earlier (they were on the passenger side), anyone have a resource for block identification for M30s out there?

Pictures in a couple days :)

[Adiabatic]

is this a white 4 door???

by the sounds of things it is.

and the tach is prob a wiring issue, esp if its b34 with and m30 harness. Mine bounces after shut off but doesn not work at all. Never looked into it yet.

Awesome project tho man, hopefully we can be alot of help, awaiting pics!

Nope, black 4 door.

The interesting thing is the fuel and water temp gauges work, and the tach self-checks to 1k RPM when engaging the starter. No response afterwards and nothing at all from the speedo. The PO had another gauge cluster and I tried it, with the same problem. The PO also said the root causes were the 2 sensors using the pickup gear on the flywheel, but I have checked these. Both are switching (hall effect sensors) and both will kill the motor when unplugged, as I figured.

Also, no reference gear on the front of the crank. Let me know what other info can narrow this down, and thanks for playing guys :)

[wildstoats]

Also, no reference gear on the front of the crank. Let me know what other info can narrow this down, and thanks for playing guys :)

Ok. Almost positive it is a B34 but how about this. There should be two "struts" that attach the intake manifold to the block. The B34 has them the B35 does not. In addition to that the strut towards the back of the engine has 2 flywheel speed sensors connectors on it. If it is a B34 that someone took the struts off of those sensors should be somewhere towards the back of the engine bay. Hope that helps.

B34:


B35:

[Adiabatic]

Yep, it's got those struts on it. Mystery solved!

EDIT: It looks pretty much exactly like your first picture. What models and years did that specific M30 come from? It would help me greatly with the vacuum lines and other various troubleshooting.

[wildstoats]

Yep, it's got those struts on it. Mystery solved!

EDIT: It looks pretty much exactly like your first picture. What models and years did that specific M30 come from? It would help me greatly with the vacuum lines and other various troubleshooting.

Should be 1985-1987 if I'm not mistaken. I don't know everything about the M30 yet :p. Now give me some pointers on how your M30 -> 318 is wired. I'm about to start on my wiring and it's making me crazy, haha.