Long Time Dream Fulfillment: E30 Street and Track Car Combo

[CubbyChowder]

More dreams came true today. Didn't think it would happen nearly this fast, but today I scored a low mile S50! Pulled from a 1995 M3 with only 109k on the clock (was able to confirm through VIN numbers and recent smog certificates/maintenance records). I'm pumped. I just couldn't pass it up. Honestly in the decade that I've been an E30 enthusiast, I've regarded an S5x swapped E30 as the pinnacle. Obviously there are better and wilder swaps out there, but it's been a dream of mine for years and I am really happy. It's gonna be a little bit before it makes it's way into the car but when that time comes, it'll be an easy swap.

Came with the full harness and DME so that was nice. I think I got a really fair deal too, considering where prices are at for everything these days.

All I want to do is dive right into this swap and get it all dialed but I have to hold off for a little, nice test of patience.

[CubbyChowder]

Have put about 200 trouble free miles on the swap so far. I had a CEL which was a good opportunity to see if a stomp test works (which it did) - code 1263 for EVAP purge valve. I didn't have one hooked up yet but I finally found a used one for sale and it showed up today, so that took care of the CEL. I also have a Turner chipped 413 ECU from a manual car on the way, so hopefully that takes care of my rev hang "issue".

Still have a bit of tidying up to do but I'd pretty much consider this swap complete and daily driveable! Gave it the beans on some backroads this evening and the car feels happy.

[CubbyChowder]

Panici Thanks! So far I'm happy with the swap. As for paint, I've only used the VHT header paint from Autozone and have had decent results, but I also haven't gone through the proper steps like using VHT primer first and all that, I usually just clean a bit and then spray away. It lasted pretty good on my M20 exhaust manifolds but it certainly has it's limitations. Looks better than rust.

[Panici]

the reservoir now sits right off the engine mount arm. I actually quite like this setup as it hides the reservoir

Gave it a quick and dirty high temp paint job.

the car as it sits is totally driveable and I'm going to put more miles on it today! I'm happy to be in the E30 again.

I did something similar with my power steering res. Keeps it tucked away, and a nice step towards a semi-shaved engine bay.

What kind of high temp paint did you use for the exhaust? I've tried a few kinds before but haven't found one I'm happy with yet.

Happy you got it on the road! Enjoy the drive

[CubbyChowder]

Alright, the M50 swap is buttoned up for the most part and the car runs and drives. Put maybe 40 miles on it last night and drove it home. The last few pieces of the puzzle:

Got the power steering system all dialed in. Had to order a new E36 high pressure hose and modify the two reservoir hoses to make it all work as the reservoir now sits right off the engine mount arm. I actually quite like this setup as it hides the reservoir:



Then to finalize the cooling system, I bought two of the NAPA 8484 hoses that are commonly used with these swaps, and they worked out perfectly. Was able to trim them up to fit just right, they look proper:



The last big hurdle was exhaust. I have been searching for an E36 midpipe to graft onto the car (hoping to get this through CA BAR) but no luck. I did, however, cut up the pipes from that E34 parts car so I at least had something that would bolt to the manifolds. So, as a temporary solution, I ended up modifying the E34 pipes to route cleanly in the E30 and then ran them into the original E30 exhaust setup. It's not ideal as I'm sure it's restrictive, but it works for now and I will change it eventually.

E34 pipes modified to fit:



Grafted on to the E30 system. I also cut the o2 bung out of the E30 exhaust and relocated it further downstream in the collector:




Gave it a quick and dirty high temp paint job:



Bolted right up.




At this point, the car was ready to drive. Had a successful maiden voyage of 30-40 miles, coolant temp and oil pressure was solid the whole time, no fluid leaks anywhere. The car actually sounds really healthy and pulls strong, definitely a nice little bump in power over the M20. The one thing bothering me though is the "rev hang" I'm experiencing. The RPM's drop slowly when you let off the throttle and researching it leads me a bit confused as the info is all over the place but seems like a common M5x thing. The thing that makes the most sense to me out of everything right now is the fact that I'm using the 413 ECU from the automatic 525i E34, and that rev hang is supposedly programmed into those ECU's and can be programmed out. I'll get it sorted eventually but the car as it sits is totally driveable and I'm going to put more miles on it today. I'm happy to be in the E30 again.

[It's Soda Not Pop]

I use VR1 20w-50

[amcp]

Hell go 10w-60.

[CubbyChowder]

Panici & 2mAn - Thank you guys for the input! Any recommendation on a thicker oil that might be suitable for this specific scenario? Like a 20w-50 or similar? I bought some Rotella T6 5w-40 to run but can always return it.

[2mAn]

Thicker oil and if you can throw in new rod and main bearings, just do that and drive the piss out of it

[Panici]

I ended up draining the oil and filter into a separate clean pan and the oil appears glittery and I’m seeing small specs of shiny non-magnetic metal flowing out of the filter and floating around in the oil. Not a good sign.

Oof that's a rough one. Always the chance you (and I) take with an unknown engine though.

My vote is to throw in a heavier "high-mileage" oil and send it. Meanwhile find a replacement 24v engine and build it up.
I bet it will last longer then you think.

It'll get your car on the road and all the gremlins ironed out. Then you can swap in the replacement engine as time allows.

[CubbyChowder]

Well…. I think my oil filter housing mishap yesterday revealed a deeper issue. I placed a clean drain pan under my engine before I pulled the housing off to catch residual oil, and I noticed that there appeared to be some glittery speckles in there. I ended up draining the oil and filter into a separate clean pan and the oil appears glittery and I’m seeing small specs of shiny non-magnetic metal flowing out of the filter and floating around in the oil. Not a good sign.





what do you guys think? I’m really unsure of what to do moving forward. Do I put fresh oil in it, cross my fingers and continue moving forward with the swap since I am so close? I’m half tempted to just continue finishing it and try driving it for a while since I’m planning on S50 swapping down the road anyways. I don’t know! I’m pretty torn on what to do. The idea of tearing all of this back apart puts a pit in my stomach.

[CubbyChowder]

OSAH racing - I can't wait to see how it feels compared to the M20! I know not to expect much, but I think I'll still enjoy the bump in power and to just have something more modern. Streets of Willow is on the bucket list for sure! I'm really itching to get back out to Buttonwillow too, hoping to get at least a couple track days in towards the end of the year.

Northern - damn that's too bad they're double the price because those sound like they'd be perfect!

AWDBOB - Thanks man, a part of me will miss the M20 for sure, it was such a great engine for the past year.

----

Alright guys, the car runs! Finished up a bunch of little odds and ends today and finally reached a point to where I could at least try cranking the car over to see if it even would. Once I verified that the car could crank, I plugged the fuel pump relay back in and turned the key. The car fired right up on the first attempt. That was super rewarding, I was excited. But the excitement was short lived because within about 10 seconds I noticed a puddle forming on the ground. It was pissing oil from somewhere so I quickly turned the car off and inspected, and found that the oil filter housing was leaking badly from one of the plugs:



What sucks is I spent a lot of time cleaning this thing up and took a lot of care in making sure I installed it correctly with new gaskets and what not, and tapped in my oil pressure sensor for my gauge. Had no idea that those plugs were an early version thing and a common leak point, learned that the hard way. I took it out and found that it was all gunked up:



But, luck was on my side. I happened to have another oil filter housing from my E34 parts car which was one of the better later model housings with the threaded plugs, so that was a score. Obviously in hindsight, I wish I had known the differences and chosen the E34 one from the get go, but I ultimately chose the other one originally only because it was less dirty. Here are the two side by side:



So it took a couple hours to tear it all back down, clean the crap out of the other housing, swap my oil pressure sensor over and all that and get it installed. Once I had it buttoned up the car fired right up and didn't leak anymore, so we are back in business. That was an annoying setback, but all in all I'm really happy that all of my hard work paid off and that the car started with no issues. My CEL works, my tachometer works, the engine sounded healthy from what I could tell but it's still too early to really say.

[AWDBOB]

Great work on the M50 swap. I must admit, I am a bit sad to see the M20 go. Makes sense though, if your end goal is S50.

[Northern]

Re: N5x exhaust studs 11127593376, yeah they're pretty short.
Seem to work fine on the OBD2 stainless headers, but need to be wound out a thread or so on turbo manifolds and I guess the OBD1 manifolds.

An alternative is the N47 exhaust stud 11128597830 it's ~5mm longer than the N54 stud.
Downside is they're double the price.

[OSAH racing]

Your going to love the M50. I have had both m20 ( 272, chip 4.10 ) and m50/ S52 head ( headers, 4.10, ) and the M50 is produces more power through out the rev range so its quicker. do you have plans to do the Streets of Willow down the road? I want to get out there in the fall.