E30 M42 Swap

[alisterh 26]

Hi,

A few people have asked my how I did my swap so I thought I should clear some myths and put it in a permanent place.

The reason I chose this swap its cheap, easy and the drive train is already capable. The e30 is my Girlfriends daily so I wanted it off the road as little as possible.

The e30 had a very ticky m40 and was on its last legs, the donor car was a 1995 318ti but any m42 car will be fine but a non ews model would be ideal.

Below is the list of parts from each car used.

e36 318ti m42	e30 m40	e30 m42
Engine	Engine arms	Exhaust Manifold
DME	Engine mounts
Engine loom (x20)	Upper and lower Oil pans
1994 DME (no ews)	Gearbox/clutch/driveshaft etc.
Power steering pump	Fan and fan clutch
Alternator	Throttle cable with part No. 13541288013
dip stick (needs bending)	Brown Temp sensor (swap with black temp sensor on m42)
Starter motor

As you can see all the parts except the exhaust manifold are from the E30 or the donor 318ti. I sourced the exhaust manifold from e30zone in the UK and was $250 delivered.

The only custom parts were the coil bracket (soon to be COP), the exhaust manifold to existing exhaust and the c101-x20 adapter.

I treated the c101 to x20 adapter just like an m50 swap, below is my adapter table

Pin No.	C101	Colour		Pin No.	X20	Colour
1	Charge light	Blue		25		Blue
2	Static oil level	Green/Yellow		1		Blue/White
3
4	Temp Guage	Brown/Purple		12		Brown/Yellow
5	Oil Pressure Light	Brown/Green		23		Brown/Grey
6	Oxygen Sensor relay	Green/White		22		Green/White
7	Switched power	Green		21		Green/White
8	Fuel rate input	White/Black		24		White/Black
9	Engine Speed imput	Black		20		Black
10	Dynamic Oil Level	Blue		2		Blue/Yellow
11	Reset Service Lights	White/Green		19		White/Green
12	Check engine light	Grey(brown)		8		Grey
13	Fuel pump relay	Green/Purple		13		Green/Purple
14	Speed signal for ecu	Black/White		14		Black/White
15	Unloader relay	Black/Green		15		Black/Green
16	Diagnostic	White/Black		17		White/Purple
17
18	Start	Black/Yellow		18		Black Yellow
19
20

Overall it was a very easy swap, this was my first time pulling an engine and was completed by me and a friend in a long weekend.

Hope this helps others in the future.

Cheers

Edited October 31, 2016 by alisterh

[polley 916]

Cool. I really like the m42 engines.

[NZ300E 44]

Sounds like a great repower without breaking the bank. When you say cheap, what do you mean.....all up......2....5.....10k.....not including labour of course because it was a diy job.  Curious to see if it might be an option for my car. 

[alisterh 26]

36 minutes ago, NZ300E said:

Sounds like a great repower without breaking the bank. When you say cheap, what do you mean.....all up......2....5.....10k.....not including labour of course because it was a diy job.  Curious to see if it might be an option for my car. 

Under 2K, donor car was $550, exhaust manifold was $250, custom exhaust work was $280, 1994 ECU was $80, c101 adapter was made from loom cuts from zebra car parts $20. I also spend $500 on preventative maintenance water pump, vacuum lines, oil, filter, coolant etc. 

It looks like your car is 320i though so some of the m40 parts you would need to find  as well. 

[NZ300E 44]

Cheers for that. Got me thinking.

[alisterh 26]

The car is now certified which ended up dragging out a lot longer than I expected mostly due to small issues unrelated to the swap. Also did a coil on plug conversion which really cleans up the engine bay.

Overall the car feels great, way more e30s should of come to NZ with this engine car feels so light and loves to rev.

Next up is a bit of a Hartge tribute (body kit and wheels)

Edit: Also forgot to mention that driveshaft loops weren't required due to unmodified driveshaft and less than 50% power increase. 

Edited March 13, 2017 by alisterh

[agent75 37]

I am very seriously keen on doing this swap.  I take my E30 to the track and love the 4 cylinder weight and feel, but struggle with the bad case of asthma my m40 has.  hmmmmmmmm.  Thanks for posting this

[HEQ841E34 0]

I'm now looking at doing this swap on my E30, did you swap over the engine loom and ecu aswell? I'm picking up a 1995 ti with everything I'll need. Where abouts are you located? Im keen to find out how it all went. I'm swapping out the old and blown M40

 

[alisterh 26]

Yeah you need to use the 318ti engine loom and you will need to find a pre 1995 ecu or buy a ews delete chip. I'm located in Auckland. The swap has gone well, the car is daily driven by my girlfriend and has never let her down. 

[HEQ841E34 0]

8 hours ago, alisterh said:

Yeah you need to use the 318ti engine loom and you will need to find a pre 1995 ecu or buy a ews delete chip. I'm located in Auckland. The swap has gone well, the car is daily driven by my girlfriend and has never let her down. 

Sweet so I'm getting a semi complete 1995 318ti body(everything except engine and wiring and ecu gone)  from Christchurch and once I get it back here to Nelson I'll get it all installed into my e30, I'll most likely make an exhaust manifold from the ti one.

Can I just find an earlier ti ecu and it will work? Or is there still more work involved? I'm very keen as I've been trying to research this so much and really glad I've found someone who has put it into writing which is going to help no end! 

Im looking forward to having a little pocket rocket e30 ??

[alisterh 26]

They ecu you need is plug and play but it's probably just easier to buy a chip from eBay for less than $40. I have heard from a few people that a m44 manifold bolts on and clears the steering linkage without modification so that may be an easier option. 

[HEQ841E34 0]

I see those chips on eBay. Once I get the m42 to mine I'll have to collect up the last bits I need for the swap as it doesn't have an alternator and starter motor or even the power steering pump with it but I I can get m44 parts in Nelson fairly easily so should be able to make something work. 

What did you do for radiator hoses? Use the m40 ones? 

[alisterh 26]

I ended up using a mix of e30 m40 hoses and the 318ti hoses. I cant remember exactly  but some required trimming. 

[HEQ841E34 0]

I've now got myself the m42 out of the ti I bought, with everything ready to do the swap. The ti I got everything from is an auto 01-1995 and i don't think it's got ews. The key reader isn't plugged in and key is the older style key. This is my first engine swap, the wiring that you did what are the ones that are crossed out in the table? 

[alisterh 26]

From memory the ones crossed out are only required if you have a overhead check panel, usually only found in 6 cylinder cars. 

[HEQ841E34 0]

I've now got the m42 in the e30 ready to finish up tomorrow/today. How did you send your dipstick tube? I can't see how I can make it work. Using the e36 one also there was two connectors on the ecu end of the m40 loom a black and white one. Are they significant to anything? 

[alisterh 26]

Here is where my dip stick tube ended up, was just a bit of trial and error really. From memory I don't remember worrying about those black and white plugs. 

[will 169]

Black and white plugs are for A/C leave them unconnected unless you have A/C.

EWS is simple to wire in so dont worry if it does have it.

[HEQ841E34 0]

I gave my dipstick tube a good bending. Will most likely need some more tweaking. Mine has a/c but not sure if I will bother trying to fit it back up to the m42 as belts are different etc. now I just need to get a top hose sorted and make up an exhaust manifold that'll work. And tidy up th wiring side.

[e30seattle 0]

Stumbled upon this forum looking for more information on ews. I have a 1984 e30 318i and it had an m10 in it as you probably know which blew so I needed a cheap "quick" swap. So doing my research I decided to go with m42 out of an 1995 e36. I got it all installed had a custom wiring harness made and got it all hooked up and it cranks over but wont start. boiled it down to the ews and was just wondering if i could get the dme out of an e30 m42 or should i get a earlier <1995 e36 ecu? any help would be greatly appreciated. 

[dirtydoogle 383]

For what it's worth it have a 94 date stamp ecu with EWS 

You can have it removed 

[e30seattle 0]

I put in the 1994 ecu into my e30 and still nothing. No fuel no spark. Could this be because I am using an e30 m42 wiring loom instead of a e36 m42 wiring loom? But the motor is out of an e36.

[eliongater 718]

That sounds like EWS? Post a picture/the number on the ECU?

[Tuonome 0]

Hi I bought an e36 318ti for a donor for my 1989 316i e30, I have stripped the e36 ti and I was wondering if the m42 engine from the e36 goes onto the e30 subframe? Or do I use the e36 ti subframe?

[nick496 268]

Pretty sure it's just the engine mounts from your old m40 go onto the m42. No subframe swapping required. Not that you can easily swap the front subframes.