m42 into a 318i

[isamemon]

all somewhat related.... not try8ing to get off subject but I saw the part about trannys and m42's

so I have two 91's with m42's. they are two months apart on build dates. the early one is a coupe, the later a vert. tow different tranny builders
one says getrig, and I could have sworn, the last time I was undr the cais it I could have sworn it said hect...maybe I was looking at the wrong thing
late at night when I looked, just got it a few days ago
Ill have to climb under them today and look again
but is this right
also the final drive says 4.1 but not have the "S" in fornt of it
so I guess my is does nto have limited slip, but I was told when I bought it , that it did

[RRRR]

Contact Jenny Morgan (CCA Tech Advisor)....She did a complete M42 swap on an early '82 or '83 build-date 318i 15 years ago. She knows more about M42's than anyone on this board. : )

Searched but cant locate her - anyone has her link?

[Stu]

Contact Jenny Morgan (CCA Tech Advisor)....She did a complete M42 swap on an early '82 or '83 build-date 318i 15 years ago. She knows more about M42's than anyone on this board. : )

[RRRR]

ull be a fool to boost the m42 instend of the m10. keep the m10. Very strong motors.

ZiMMie

Love the wheels you run in your sig. :bow:

What are they and possible to still get used ones?

[Mr Deagle]

NOTE: the stuff below is for an E to I swap, but it may pertain to a m10 to m42 swap

Round Connector >> Rectangle Connector
1 >> 1
2 >> 2
3 >> 3 (not used at all)
4 >> 4
5 >> 16
6 >> 6
7 >> 10
8 >> Not used
9 >> Speed signal (run wire to C104 in glovebox (black wire))
10>> 15
11>> 17
12>> Not Used
13>> 7
14>> Not Used
15>> Not Used
16>> 11
17>> Not Used
18>> 8
19>> Not Used
20>> Run to a good ground

[Hick]

I believe early cars had a different, rectangular (as opposed to round) C101, so he'd have to make a wiring adapter. It shouldn't be too hard to figure out.

They still have some sort of plug for the engine harness. I think you are correct

[FredK]

I believe early cars had a different, rectangular (as opposed to round) C101, so he'd have to make a wiring adapter. It shouldn't be too hard to figure out.

[Hick]

i THINK theres no C101 plug on the chassis side of the 318i. Dont quote me, i have had an 83 and 84 318i and i dont think either has the plug.

This doesnt mean its impossible to swap motors, just that it may be pain as far as wiring the motor is concerned. You may be able to get away wit removing the old engine harness and simply powering the M42 ECU to run the motor, but again thats just a guess.

I swapped an m42 into an m20 chassis with very little problems. The only issues i had were that of the C101 plug [chassis side had a ground, motor side had a power wire] and removing and welding in the mounts for the m42 coil pack and air box. Aside from that it was rather painless.

[FredK]

Yes, I think the M10 318i only had two fuel lines running to the front of the car, but they did have provisions for fuel expansion according to the ETK (realoem.com). I'm not sure where, but the car had a charcoal canister and expansion tank.

So, you shouldn't need to install the M42's charcoal canister. However, that leaves the issue of the electric valve that the DME will likely want to see, otherwise it will store an EVAP code. I believe the solution is to plug in the valve, let the hose dangle off the throttle body, but plug in some kind of small filter on the opposite side of the valve.

That leaves the issue of the pump. I don't think it'll matter too much. I mean, you're blowing 90 to 100 psi on two cylinders. You need to lean out the mixture anyway. HAHAHAHAHA.

HA.

HA.

HA.

No but seriously, I think the m10 fuel system is fine. It's the two pump system, right? There's an in-tank pre-pump and a main pump, the same system as the 325e. So, it should be fine.

[thejimlab]

thread back from the dead. I have everything ready to come out. My biggest concern is fuel. Anyone have any idea if I will have to change fuel pumps? What about fuel lines? Is that charcoal cannister necessary? I don't think the m10 fuel system has a third line.

[moatilliatta]

hows the progress?

[thejimlab]

ull be a fool to boost the m42 instend of the m10. keep the m10. Very strong motors.

I have no plans for boosting. I just wanted to keep the handling characteristics of the 4 banger and get a little more power. All of the m42 owners really seem to love their cars, so I'm going to try this swap.

[ZiMMie]

ull be a fool to boost the m42 instend of the m10. keep the m10. Very strong motors.

[thejimlab]

I bought an m42 parts car yesterday. I should have everything I need for swappage, and then some. Is there anything extremely important that I need to know?

[2002maniac]

The M10 shares the bellhousing with the M30 and S14. that's it. You need a 240 from a M42 car. Not hard to find for about $100.

Tranny from a M20 or M50 car would work too but they are heavier.