e30 repower. M10 --> M20b25

[325iRod 135]

Picked up a spare M20b25 this time last year (Jan 2021), planned on rebuilding the engine and using it as a spare for my other e30 that I had recently (in the last 6 months) finished bringing back to a condition I was satisfied with. Got a bit bored with not having an e30 to tinker with so decided to buy a second, this time a 1987 318i that came with a genuine Mtech 1 kit.. both in reasonable condition but needing some work. 

Before the 318 arrived I'd decided I wanted to repower it with my spare M20b25, so started to assemble some parts that would be required for engine swap and upgraded drivetrain. This 318 was auto so would obviously require the appropriate manual parts to complete the conversion.

Dropped the m20b25 off to the engine shop for almost a full overhaul? Bearings, rings, bores honed, block & head resurfaced, test head and install new seals. Had manual fly wheel resurfaced at the same time. I got the engine back and put it back together myself, thankfully as you all know these are pretty easy to put back together and very enjoyable.

After completing the engine it was time to remove the M10 and front rear/subframes, removed subframes so new bushes could be installed. Went with Powerflex bushes after using them previously and being pretty happy and easy to get. While the subframe/s, struts are out I dropped them at a mates shop for sand blasting and paint. Decided to Clean the engine bay and get under the car with degreaser, hot soapy water a hard brush and water blaster to remove 30+ years of dirt. It wasn't a fun job but I am pretty happy with the results. 

Upgraded front brake calipers to stock 325 calipers that take vented discs and while I was there grabbed a purple tag rack and upgrades the steering.

Installed M20 loom and 173 ECU, located battery to the boot and put new M20 engine into the 318 for the first time and connect the dots with the wiring. I wish I could say she started up 1st time but I had the leads around the wrong way (maybe a couple to many beers the night before?) but at least it was an easy fix.

The original plan was to repair the damaged panels (usual carpark dings) and re spray it in its original color Alpine White but I'm having second thoughts.. do I change color to Brillantrot?

Here's the 318 as it arrived at my house

 

Engine as purchased 

Head back from shop

this is the only picture of the block I can find

 

 

Subframes coming out

 

 

 

 

Brakes and Rack

Engine and loom

Very Short video of 1st start after fixing leads

 

 

 

 

 

 

 

Edited January 28, 2022 by 325iRod
edited

[Gaz 1060]

I did wonder what you were up to collecting all these parts when your one was mint!

[325iRod 135]

3 hours ago, Gaz said:

I did wonder what you were up to collecting all these parts when your one was mint!

Yeah.. knew i'd need something to keep me entertained 

[TriniGT 2]

How easy of a swap was it from the M10 to the M20B25 harness-wise?  I am doing the same swap, I have a complete engine with engine harness and no ECU.  I will be using an AEM infinity as I will be turbocharging my setup and looking at doing a Coil-over-plug setup.

Any advice is appreciated.

[325iRod 135]

2 hours ago, TriniGT said:

How easy of a swap was it from the M10 to the M20B25 harness-wise?  I am doing the same swap, I have a complete engine with engine harness and no ECU.  I will be using an AEM infinity as I will be turbocharging my setup and looking at doing a Coil-over-plug setup.

Any advice is appreciated.

Very easy, the harness goes through the firewall and is sealed with a large rubber gromet.. getting the rubber gromet in/out is probably the hardest part but plenty of silocone spray helps.

Nice build, keep us updated along the way! Eventually I would like to install RHD throttle bodies in this old girl 🙂

[TriniGT 2]

Okay so just to make sure, there is only one harness from the engine to the ECU, as in there is no plug connector separating the engine harness before it is fed into the firewall to the ECU?

[325iRod 135]

I've Owned this car April 21 and its never has a wash, to be fair for most of that time its been sitting outside on axels stands under a car cover or in the garage with no engine / drive train. Anyway.. yesterday was a pretty good day in CHC so took the opportunity to give the exterior a bit of a tidy up. It still has a long way to go.. a few dings and scrapes but definitely a lot better than it was. 

My goal is to have this car in the panel & paint shop to fix up its imperfections and full respray in the next 2/3 months / over winter.

After the giving her a good old wash, I remembered that last time I drove her the steering was way off, so as I was feeling motivated it was time for a backyard wheel alignment. I was never going to get this perfect but at least now at a glance the front wheels appear to point in the same direction. One day (probably after panel & paint) she'll get a proper wheel alignment but for now my best effort will have to do  

After all that took her down the end of the street (very gingerly) for the 1st test drive since installing the manual gearbox and m20b25, the car felt great.. cant wait until its all legal and road worthy and take her for a proper drive!

Very quick photoshoot while I was out

[Sammo 2544]

Damn, a Tech 1 and a Tech 2 #goals

[325iRod 135]

1 hour ago, Sammo said:

Damn, a Tech 1 and a Tech 2 #goals

@Sammo It is nice having both, I spend a lot of time in the garage staring at the 2  

I have 3 BMW's at the moment but my end goal is to sell one of the e30's and the e92 335i and buy an M3. 

[325iRod 135]

A couple of months ago I acquired a 14.5mm rear sway bar and also picked up a 3.75 medium case diff. 

I finally got around to installing the rear sway bar and diff a couple of weekends ago. I've been finding motivation is hard to come by in these cold dark winter months but felt good to be giving the old girl some love. I had a small case diif that I used when re-installing the fresh rear subframe so I had to remove that before installing the medium case, I decided to make the job a little easier by removing the half shafts to create a little more space. Pushed out the old rubber bush on the diff hanger and installed a new power flex bush. Installing the medium case diff was pretty hassle free but reinstalling the half shafts proved to be a right pain in the backside!! It took me several attempts over multiple nights, lots of cleaning and filing away any small imperfections on the splines, finally managed to to get the splines aligned and pushed into place. I suspect this job would have been much easier with 2 people and a hoist rather that on my back in dimly lit garage. 

 

 

 

 

 

I knew when I installed the manual conversion on this car the shifter would need replacing as you can see above it is far from pretty.

After reading one of @Sammo posts I decided to go with z3 1.9 shifter, installation was quick and easy - a quick win all round.

Going from no rear sway bar to a 14.5mm sway bar and new shifter I was very impressed with how the cars feeling.. having a sway bar has made a huge difference to the feel of the back end and I'm amazed at the difference the new shifter has made.

Next up for this build..

Converting 4 door sport seats to 2 door following this article..

 

 

[Sammo 2544]

Good work! How easy was the diff  hanger bush?

I've got an 80a Garagistic one to go in mine at some point, looks like getting the old bush out can be a right pain without a press?

[325iRod 135]

@Sammo I started with a press but couldn't find anything that was the right size to push it out, was only pushing the rubber.

So I drilled out the centre rubber piece and used a hacksaw to cut out the outer metal ring, once the cut was made it tapped out easy with a big flat head and hammer.

All up it took 30-45 min, not too bad at all  

[Sammo 2544]

38 minutes ago, 325iRod said:

@Sammo I started with a press but couldn't find anything that was the right size to push it out, was only pushing the rubber.

So I drilled out the centre rubber piece and used a hacksaw to cut out the outer metal ring, once the cut was made it tapped out easy with a big flat head and hammer.

All up it took 30-45 min, not too bad at all  

Good to hear - that was the technique that seems to be popular - did the new poly bush push in by hand?

[325iRod 135]

@Sammo yeah it was easy enough to do by hand.. just pushes in. My one was in 2 halves, if yours is the same you wont have any trouble.

[325iRod 135]

Been stripping this old girl down as much as I can before it goes into the paint shop on Saturday. 

I should get most of done, but will leave front and rear windscreen for the professionals.

Cant wait to get it back with a new coat of paint, then ill have to put it all back together again  

[Neil McCauley 394]

Front and rear screens are super easy to do yourself, the trick is not bending the (now unobtanium) chrome / shadowline centre metal clip. Getting them back in... Find someone you hate and ask them to do it 😁

[325iRod 135]

@Neil McCauley thanks for that, I've been ignoring the centre locking piece hoping to make it someone else's problem / whoever tackles it has a good solution for it. I had a quick look this morning and the "decorative strip" that goes into the seal isn't cheap so hopefully that comes out ok and can be rejuvenated / refurbished somehow.  

[325iRod 135]

@Neil McCauley I sent a query into CHC BMW for all the parts below apart from main seals (weather strip) and all are available ex Malaysia for just over over $400 inc GST.

Not a bad price I thought. 

 

 

[325iRod 135]

On the way to the paint shop, happy days  

[325iRod 135]

Got the car back from paint shop late last week, spent the last few days putting it back together.. exterior is almost complete but have a lot of work to do inside.

I was really unsure about repainting it white but I'm very happy with how she's turned out. What colour number plates should I go with? (seem to be pretty topical at the moment). 

A few pics of it in the driveway.. really looking forward to it getting some new wheels (more to come here).

[E30 325i Rag-Top 2956]

I would think that would look really sweet with the new black and silver plates. The white body with black details is always a classic combo I feel.

[325iRod 135]

3 hours ago, E30 325i Rag-Top said:

The white body with black details is always a classic combo I fee

Yeah, I think it is as well but until now liked the look more on modern cars, my 335i (e92) is white\black and I love it. 

Also agree with you re the black & silver plates, that should finish her off nicely. 

[E30 325i Rag-Top 2956]

I also kind-of think that the black plates look better on older/classic cars, they don’t seem to look right on new cars to me.

[325iRod 135]

Been able to make some pretty good progress with the old girl over the Christmas break. First off I acquired some 15" basket weaves from a fellow Bimmersport member a few weeks before the break  

I'm still not sure what wheels I'll end up with on this car but I thought 15's would look better than the 14" weaves its currently sitting on, also always wanted a set of 15's. I've got 2 new waffles sitting at BMW for me to pick up and 2 more on the way. 

They don't look to bad for a quick home refurb job, one day they will get a full restore.

before..

After..

Got these RS's and slightly bigger lips (nothing to crazy) earmarked for the white coupe as well, these will get the full treatment (curbing removed, polished lips, repainted faces and new / refurbished bolts). Probably over the winter months. 

 

 

 

[325iRod 135]

The dash in this car wasn't to bad, only one crack in the standard e30 position. However, I've had a mint one sitting in storage for a few years now and I've been waiting for the right time to put it to use. So, out with the old and in with the new.

I think this is the 3rd attempt at pulling out and refitting e30 dash, not a bad job certainly not as daunting as one may think - IMO the worst part is refitting the heater duct controls and associated clips. 

I don't have to many photo's of this process but here it is with the old dash completely removed..

 

While I was in there, I pulled out the old blue carpet that was pretty tatty and installed a better looking blue replacement that came into my possession from a friends parts car. 

Replaced as many of the seals in the air box as I could with new sticky foam from Bunnings.

And retrofitted an OBC to replace the analogue clock, the only piece I need to complete the job is a piece of loom that connects ambient air temp and OBC horn. If anyone has this piece (including ambient air temp sensor) and don't need it I would be more than happy to purchase it from you. 

Re-installed and everything worked - Very happy boy!