M30b34 E30 twin-screw supercharged muscle car

[ThatOneEuroE30]

So from what I understand, one can run a m30b34 on a m20b25 harness with m20b25 management, by the adding m20b25 plug wires with the pulse sensor (which I have), a m30b35 harmonic balancer, mounting the CPS in the exact correct place, and lengthening some wires here and there. That doesn't sound so baaaaaad.



I've heard of this being plausible, but I've never actually read a thread about it. I could just order the kit from the e28 guy, but this way could be a fraction of the cost. Sure, time is money, but I'd rather be "making some money" building a car thing than working under someone's house on floor joists.

Yup your gonna need to change the coolant sensors and oil pressure switch as well.

[slammin.e28]

So from what I understand, one can run a m30b34 on a m20b25 harness with m20b25 management, by the adding m20b25 plug wires with the pulse sensor (which I have), a m30b35 harmonic balancer, mounting the CPS in the exact correct place, and lengthening some wires here and there. That doesn't sound so baaaaaad.

I've heard of this being plausible, but I've never actually read a thread about it. I could just order the kit from the e28 guy, but this way could be a fraction of the cost. Sure, time is money, but I'd rather be "making some money" building a car thing than working under someone's house on floor joists.

I always thought you could run the M30 on the M20 harness....but needed the proper 179 ECU, etc.

I will admit to a folly. I had a brain fart and got the 173 and 179 ECU mixed up in a discussion, so if you're reading something from me to that extent, disregard it. I was set straight.

[Ether-D]

So from what I understand, one can run a m30b34 on a m20b25 harness with m20b25 management, by the adding m20b25 plug wires with the pulse sensor (which I have), a m30b35 harmonic balancer, mounting the CPS in the exact correct place, and lengthening some wires here and there. That doesn't sound so baaaaaad.

I've heard of this being plausible, but I've never actually read a thread about it. I could just order the kit from the e28 guy, but this way could be a fraction of the cost. Sure, time is money, but I'd rather be "making some money" building a car thing than working under someone's house on floor joists.

[CorvallisBMW]

More to it. M1.3 has a sensor on the plug wires, so you'll need a set of B35 wires.

You can run M1.3 (179ecu) on a late (88+) M20 harness. The 88 (maybe 87...I can't remember off hand) harness will not have the fuel injectors encased in a plastic housing. The later ones will, so you'll have to take them out of the housing.

IIRC the ECU bolts right up because M1.1 and M1.3 are very similar.

Bimmerguy2002 on mye28 has a nice list of everything you'll need.

I don't need to convert an m1.1 to 1.3, I'm just trying to gather info on the differences.

BTW, does anyone know if the m109 745i motors were all m1.1? Were they ever made in 1.3?

[ThatOneEuroE30]

More to it. M1.3 has a sensor on the plug wires, so you'll need a set of B35 wires.

You can run M1.3 (179ecu) on a late (88+) M20 harness. The 88 (maybe 87...I can't remember off hand) harness will not have the fuel injectors encased in a plastic housing. The later ones will, so you'll have to take them out of the housing.

IIRC the ECU bolts right up because M1.1 and M1.3 are very similar.

Bimmerguy2002 on mye28 has a nice list of everything you'll need.

Yes Bimmerguy2002 is who i bought my kit from cost me like 250 shipped

[slammin.e28]

Is the b35 harmonic balancer all that's required to run m1.3 on a b34? Or is there more to it?

More to it. M1.3 has a sensor on the plug wires, so you'll need a set of B35 wires.

You can run M1.3 (179ecu) on a late (88+) M20 harness. The 88 (maybe 87...I can't remember off hand) harness will not have the fuel injectors encased in a plastic housing. The later ones will, so you'll have to take them out of the housing.

IIRC the ECU bolts right up because M1.1 and M1.3 are very similar.

Bimmerguy2002 on mye28 has a nice list of everything you'll need.

[CorvallisBMW]

^ True dat, my nizzle.

I may have a b35 harmonic balancer coming soon. That will enable me to use motronic 1.3 on this here b34. I feel like I've read that a m20b25 harness, appropriately lengthened, can be used to run this motor with stock m20b25 management. If that's the case, do I use the m30 afm or the m20 afm? I imagine I'd use the m30 one, but who knows.

Yes, m30. IIRC the only wires you have to lengthen are O2, possibly the AFM, and maybe 1 more. Easy.

Is the b35 harmonic balancer all that's required to run m1.3 on a b34? Or is there more to it?

I'm planning on using my m20b25b harness on the m30. AFAIK, the components unique to the m30 are only the afm, injectors, o2 sensor, and 179 dme. Oil pressure, tps, cps, and coolant temp sensors are all the same.

And I believe the o2 sensor itself is the same sensor type, but due to it's location on the exhaust, it has a much longer lead on the e28/e34 than the e30.

Correct on all accounts :up:

[Ether-D]

It's on!!

[Andy.B]

Haha. I was pretty annoyed that after going through the gf's car and swapping to a 5spd while getting everything sorted out a rod started knocking, but I guess it leaves me with only an m30 swap on my hands, as opposed to EVERYTHING left like you have.

We will have to see who finishes first... You may have a running engine quicker, but mine may be drivable sooner.

[Ether-D]

So I guess the hard part is done. The tedious part is ahead, what with putting the car back to driving condition.

There is nothing but hubs at the trailing arms. The trunk is full of 1,000,000 rear brake parts and a couple axles, a bunch of random interior bits, and some random e36 crap.

In the front, the suspension is out but nearly complete I think. Tie rods are bad, control arms are bad and no CABs. The calipers are still attached. The booster is in the passenger floorboard, and this car was an auto.

Plus exhaust and interior.

What's that, about 2 months of crap?

[Ether-D]

Got a decent used drive shaft and guibo today. Gonna put em in tommorrow evening. Hizzel yizzel my nizzel.

[Ether-D]

Ok, werd.

I'm gonna use the m20b25 harness just because of how easy it will be to go MS2 later when the supercharger moves into town.

I have not figured exhaust out yet. My good buddy Kevin has offered to help me with welding up an exhaust. I don't know what it is gonna be yet, but I know I want it to be heard before it's seen. Not godawful loud, but it's not gonna be a DD. It's a muscle car. It should sound muscular. Like, "Lublublublublublublublublub H-RUM, WAA-AAAAMP, WAAAAAAAAAAAMP, WAAAAAAAAAAAAAAAAAMP!!!"

Then once it's supercharged, take about three of the "A"s out of each gear...

[ThatOneEuroE30]

You guys are both correct. It is easier though to use a b35 harness cause then there is no extending required. Also you can run a m30 on a 173 dme all day longbut it will run much better on a 179 cause that's the unit meant to control that engine. The problem with the m20 harness is the injectors the m20 harness has a case that plugs into all the injectors where as the b35 harness has individual leads to each injector like the b34 harness. BTW my shop is the same way haha except I have a 1 stall garage with a press, welder compressor, work bench and three tool boxes plus my car shit gets crammed I gotta pull everrything out of my grage and completely put it back together atleast every couple months so I can find all the tools iI lost in the process haha.

Andy and Ether have you guys decided what your gonna do as far as exhuast? or is it still to early yet

[Andy.B]

I'm planning on using my m20b25b harness on the m30. AFAIK, the components unique to the m30 are only the afm, injectors, o2 sensor, and 179 dme. Oil pressure, tps, cps, and coolant temp sensors are all the same.

And I believe the o2 sensor itself is the same sensor type, but due to it's location on the exhaust, it has a much longer lead on the e28/e34 than the e30.

[Ether-D]

^ True dat, my nizzle.

I may have a b35 harmonic balancer coming soon. That will enable me to use motronic 1.3 on this here b34. I feel like I've read that a m20b25 harness, appropriately lengthened, can be used to run this motor with stock m20b25 management. If that's the case, do I use the m30 afm or the m20 afm? I imagine I'd use the m30 one, but who knows.