Putting a m42 in a m10 e30?

[2mAn]

If the car is already a 5 speed, I would just swap a M30 in

[TobyB]

I meant 24v swaped

You guys got 24v four cylinder engines??? You really DID get the good shit!!!

(:p:D:p)

hee

t

[glnr13]

If the car is already a 5 speed, I would just swap a M30 in

i can vouch for this :)

if you go this route you'll need an ETA 5 speed driveshaft and an e30m3 flywheel/clutch/pp or the bigger 2002 flywheel with stage1 or better clutch/pp.

plus the regular m30 bits needed for the swap as posted in several other threads.

[irish44j]

Well,

You'd be losing .2L but adding a cam. Honestly, I don't think the ends justify the means.

Please elaborate how the 1.8L M42 has more displacement than a 2.0L M10?

There is a huge difference in speed and feel between an M10 E30 and M42 E30. I wouldn't go spending big bucks to make the swap though.

At a minimum, you would need:
- M42 engine
- M42 wiring harness
- M42 ECU
- M42 Fuel pump and probably some of the related hoses for the system
- m42Engine mounts
- Getrag 240 transmission
- Tranny brace and mounts (if different than what is on the M10 car)
- M42 driveshaft
- Small case 4.10 diff (not sure if the M10 cars had one already)
- M42 radiator and coolant hoses
- M42 throttle cable assembly
- M42 exhaust (cat-back and muffler)
- M42 O2 sensor

There is probably other stuff needed but it is slipping my mind.

I've done the swap. I'm using the original M10 fuel system in its entirety (dual pumps, etc). Tranny mount is the same. Tranny crossbrace is the same. I think I used the M10 driveshaft as well (don't quote me on it though).

My '85 had a factory 3.91 LSD small case, which is damn near perfect for the M42 (IMO).

The M10 was fine. Stock for stock the M42 is far better in every way except sound. Nope, it's not an M20 or M50, but it's a more modern engine and it feels like it, and it has ~40% more power, and it feels like it. A chip wakes it up nicely and gives a higher redline as well. It's a fun engine that likes to rev. A bit buzzy if you're using solid motor mounts is the biggest downside, but less of an issue for a street driver with OEM liquid-filled mounts.

And it gets way better fuel economy, if you care about that kind of thing.

All in all, a pretty easy swap, just get all the M42 stuff out of an M42 car. The toughest part is splicing the wiring harnesses, and that's really pretty simple. Otherwise, it's pretty much drop-in.

It's a simple swap if you buy all the M42 stuff together. Both my M42s came with tranny and wiring and radiator, so it was that much easier.

You do need to find a place to mount the ignition coils, and if you buy the engine, be SURE to label which wire goes to which coil from the ECU before you unplug it....else you'll be spending time with your multimeter, lol.

Anyhow, I did a full swap documentation from M10 to M42 in my build thread - look around winter of 2012-2013 (It's a long thread). It should cover every aspect of the swap, with lots of pics...

[irish44j]

m10 e30's came with 3.64 open small diff

mine came with a 3.91 LSD from the factory....

[glnr13]

mine came with a 3.91 LSD from the factory....

you're right, i forgot about the option of LSD. i think they also had option for 4.10