M42club.com - Home of the BMW E30/E36 318i/iS

DISCUSSION => Swaps, Turbos, Buildups => Topic started by: thejimlab on March 06, 2007, 05:09:43 PM

Title: m10 to m42 swap
Post by: thejimlab on March 06, 2007, 05:09:43 PM

OK guys, I have a complete 318is parts car, and the m42 is going into my 318 circa 1985. Any idea what has to be changed aside from the obvious (motor, tranny, harness, ECU) Do I have to change any of the fuel lines? I'm thinking the fuel pump has to be changed. If anyone has evcer done this, please let me know.
Jim

Title: m10 to m42 swap
Post by: m42 fan on March 11, 2007, 09:06:27 AM

I have no idea, but just wanted to say good luck.  Looking forward to updates

Brian

Title: m10 to m42 swap
Post by: Vladi on March 11, 2007, 03:49:35 PM

You'll need the rear disc brakes. The M10 has an external fuel pump if i'm not mistaken and the M42 and M40's in the tank.

Title: m10 to m42 swap
Post by: Noel Higa on March 17, 2007, 06:57:17 PM

Here are a couple of PMs I got from a guy named Rob on another board.  He is attempting to get an m42 into a similar vintage 325 shell.  I was hoping he would solve all the problems and let me know before I dive into the same swap you're talking about.  I've had several people tell me, "no sweat, no problem", but I've never seen any postings from anyone who has actually done it.  Rob is confirming my suspicion that it's tougher than it seems it ought to be.  See below:

"I test fit the engine into the car today. Using E30 M42 motor mounts it dropped in, but there are a few challenges:

The charcoal canister needs to be relocated.
The powersteering hose from the pump to the rack may need to be modified. I have an E36 M3 rack in the race car so I can't be sure how it will work on yours, but be prepared.
The top radiator hose will not reach the radiator as the radiator in a 325 is wider. In addition, the hose bosses for a 325 may be larger in diameter but I'm not sure yet.

I'll have a custom throttle body setup so I can't tell you much about that or any of the wiring as it will have a Tec3 ECU. I've also done the Coil On Plug conversion so I can't speak to coil location either.

Good luck,

Rob.

Quick update... There are more challenges than I previously thought. The tranny sits farther forward so you'll need a M42 prop shaft as well as the shifter linkage and support. I'm not sure what I'm doing about the tranny mounts as there is a real problem there too, and only the 4 main tranny bolts match."

Title: m10 to m42 swap
Post by: deni durrell on March 26, 2007, 11:44:12 PM

I am doing a similar project. Going from a '91 318is to a M10-based 318i, '84. At this point I have gutted the '84 of everything interior (incl. hvac), removed the suspension, pulled the transmission out, and emptied the engine bay (including all wiring harnesses, and MBC+booster. I have pulled as much as possible from the parts car with the intention of transferring it to the '84. I've gone so far I've been thinking of only using the 318i on the track since I know that I didn't spare anything original. And although I've got the M42 + trans in the car, I'm sure I'm not even 25% of the way there. I was thinking, "the more I take out, the more I will have to figure out to be able to put it back". Oh well.

Although I have to say that I am far from done, all the things mentioned in the previous msg were right on; in addition, the engine mounts didn't fit. The M42 mounts are closer together, the older mounts sit further apart. I used the old mounts just so the engine would have something to sit on.  I may have read some threads here that go over which ones to use (e.g., 5-series?).


(http://www.ddurrelltech.com/bmw/318i/mount-sm.jpg)

All in all, I am trying to use as much as possible from the parts car to the 318i. Not sure about the ABS just yet. It looks like new tubing will have to be used, some of it is too hard to remove without damaging it. I had to drill out the screw that holds the igintion, with that the steering shaft came out easily; i'd like to use the same door locks; I will be using the M42 radiator; hopefully the power windows and black trim too.

(http://www.ddurrelltech.com/bmw/318is/318is-engine_bay.jpg)

(http://www.ddurrelltech.com/bmw/318is/318is-front-w-susp.jpg)

(http://www.ddurrelltech.com/bmw/318is/318is-side-left-w-susp.jpg)

(http://www.ddurrelltech.com/bmw/318is/318is-side-left-int.jpg)

The 318i..........

(http://www.ddurrelltech.com/bmw/318i/318i-interior-back.jpg)

(http://www.ddurrelltech.com/bmw/318i/318i-interior-side.jpg)

(http://www.ddurrelltech.com/bmw/318i/318i-left.jpg)

Title: m42 swap
Post by: jbuttenshaw on March 31, 2007, 08:11:02 AM

i did this swap, its not too hard, u can file out the m10 cross memeber to fit the m42 mounts, i put an e36 m42 in mine though so it was easier wiring wise, if u can get the computer on the loom i can tell you the wires that need to be connected to get the dash intergrated etc. stock tailshaft fits, u can bolt up one bolt from the gearstick support and it works alright, i used commodore fuel pumps whichi guess u lot will not have being non aus. i used an in tank feed pump and the stock early e30 surge tank with a high pressure pump after it, without that is lost fuel around corners sometimes. good luck, i'm hapy to answer any questions.

Title: m10 to m42 swap
Post by: thejimlab on March 31, 2007, 02:55:55 PM

any wiring information would be great.
Thanks,
Jim