VIN #336 Craigslist Find. S38 Swapped Euro E30

[tschultz]

I took a few photos of the track day and thought I'd share them here just because I like looking back at the history. Pretty crazy to think it has been 7+ years since I test drove it once. I didn't get a ride but it was cool to see out there... on the straight it looked pretty fast! Also good that the brakes lasted without issue.










The '84 318i M42 'Melony' was also out there for the track day as a test day as well as the little 1600.

[downforce22]

Took it to a track day this weekend. Coolant hose split and leaked before blowing a couple miles from home.

Here is some on track shennanigans. Will need better tires next time I get out there, couldnt carry much speed through the corners as the back ends was stepping out.

https://www.youtube.com/watch?v=n5Wy6cKThhI

[e30m3s54turbo]

Any up dates on your car.
In two weeks I’m going to install my s38 b36 in my e30. I made my motor mounts to fit around Hartge oil pan.

[fronton]

Great read. Incredible find and I love that interior. Have you weighed it yet?
Cooling is definitely one of the most difficult aspects of S38B36 e30s. Coming up to ten years on my setup and not a single issue once it got dialed. Without AC, on a 100 degree day I tap out long before the cooling system would. Once you have enough cooling power you still need to make sure you have it perfectly bled, which is no easy feat.

[econti]

Yeah, as much as I like the -idea- of a S38 in something, everything just costs a silly amount for them. I'd love to add a E28 M5 to the fleet but throwing that many dollars into it just to make sure the valvetrain doesn't self destruct is difficult to stomach.
However as BMW are now pushing the classic parts idea, hopefully things will be made again and for more reasonable prices.

Either way, great thread, good to see you getting back into it.

[downforce22]

It is hard for me to believe it has been like 3 years and I have had the car sitting for so long without doing much to it. I have found I tend to get interested in things and get burnt out for a while and then go back to them later. Lately just getting back working on this with the probably solution to the loud valvetrain has got me back to looking into the S38.

As I alluded to before about things disappearing, it appears most S38 swaps were coming to an end by 2015. First the supply of engines has been reducing and by 2015 the newest S38 would be 20 years old by then and reaching end of life as daily drivers. Also, the recent boom in e30 m3, e28 M5, and e34 M5 values over recent years proves that the early 2000s/2010s were the bottom of the market and these cars have turned into a more collectible car. Sad, but true. Most forums posts seem to have come to a general consensus that an s38 swap would cost 10k-20k back then based on chassis, engine, and condition. Resources like motor mounts and e30 s38 swaps have been declining and documentation of this stuff on forums have also been declining. Some parts are NLA and or ridiculously expensive. I saw a thread on m5board where a MAF from the s38b36 cost $3500 + core charge from pelican parts! Looking into the swap and reading about the car and Lucifer's Hammer e28, you realize the R&D that went into these engines in the mid 80s to 90s and that these cars were not cheap then. This is a true racing engine for the street. I think you can appreciate things more when you know the history of them rather than just what it is in front of you. It would be like seeing an old slow car vs realizing it was a ford model t that changed history.

With all of that said, I am glad I have left the car sit for so long, waiting. It wasn't hurting anything sitting here and I can keep ironing out details one by one.

Ok, back to the car. Ever since I got it, the tachometer back light did not work. I had been considering sending it to Bavarian Restoration for them to have a look, but all the wiring i had been doing on the other car and solving the intake plenum gave me the confidence to tackle it. I pulled out my space clusters and spare SI boards to see if I could narrow down the problem.

First thing to note is a purple wire. This was connected to the green housing on the cluster which normally goes to cruise control (C6 I think). The original wire color is blue yellow. Well this car doesn't have cruise. It also doesn't have a yellow C3 connector since it only has a euro clock. The purple wire goes to the ecu to a black.white wire which I believe is tachometer, speed signal, which is pin 29 on the e34 m5 pinout.

20200727_191856 by tee scz, on Flickr

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So after pulling the cluster I checked the coding plug which may be specific to the m5 or maybe euro tachometer and obc module. Either way it works. I believe the e34 m5 came with an 8k tach which I don't see needing. If it ain't broke, no need to fix it. While I was in there, I found this on the euro fog light. Looks like I will need to repair that to get it working again.

20200727_191948 by tee scz, on Flickr

Then I pulled the SI board out. It looks like the OBC light had seen better days. I had a spare and was able to swap it with bulbs that weren't burnt and didn't have black coloring on them.

20200727_194611 by tee scz, on Flickr

Here were my spare SI boards for the 86+ cars. The earlier clusters have different pins but these all were lithium batteries. I chose the one where both batteries read 2.7 V. This should help ensure everything on the SI board works right.

20200727_194921 by tee scz, on Flickr

After looking, the back housing board may have a burn or something so I contacted Greg's M from Bav restoration and he let me know that this was not the problem with my cluster.

20200727_195457 by tee scz, on Flickr

I checked the bulb, it seemed back so I replaced it as well. There may have been 2 problems with it not working, but this way now I can eliminate one more potential problem.

20200727_195633 by tee scz, on Flickr

Interesting thread on bypassing the SI board for future reference https://www.mye28.com/viewtopic.php?f=3&t=94937

Ultimately, I couldn't find a problem on the board and decided to replace it with one form my spare cluster with broken mounting ears. They appear the same though one is motometer and one is vdo. After confirming the spare cluster backlights work, I took it apart and replaced it to the housing with the good mounting ears. I had to swap all gauges but that was no big deal. Looks like I forgot to get pictures but now the backlighting is working properly and I have light on the most important temp gauge for night driving.

Last thing I did was look at the stereo wiring. Ever since I got the car, it would reset the radio every time with a turn of the key. I figured there was no power getting to radio in the form of constant 12v. The switched power was working right. Normally that is red/yellow/orange on radio wiring. I got in there and found the switched and constant 12v power were hooked up wrong. I was able to swap them and now the radio works correctly with memory function and it does not reset when the key is turned off. As it turns out because of this issue I have not even listened to the cd in the radio, or stereo system while driving as it would default back to standby mode.

20200729_185328 by tee scz, on Flickr

With that button up, I am waiting on the shims from VAC motorsport. I picked up two in the size that vac didn't have from the dealer at a disappointing $23 each. As my e30 friend says, S38 = Rolex. I also received the correct thermostat from FCP euro. I will probably drill a hole in it to help the bleeding process and use that. Perhaps the old tstat doesn't actuate at the right temp, or doesn't actuate correctly.

In the mean time, I had to compile all of the S38 swap build threads I could find. The dates on these go back a few years and I didn't include thread without pictures. All of this is helpful as most other s38 e30 swaps have cooling problems. I am sure there are more, but with these links all in one place it makes it appear that the S38 is a common swap. It is not common and in 2020 it is even less common. To give an idea of engine numbers:

E26 M1 M88/1/2 Europe 453 (399 roadgoing) uses ZF dogleg, mechanical injection
E24 M6 S38B35 North America 1,767 (135 of those were canadian)
E28 M5 S38B35 North America 1,340 (101 of those canadian)
E23 745i M88/3 South Africa 208 (SA only)
E30 M3 S14 North America 5,300 (18,843 total production worldwide)

E34 M5
HD91 (ECE-spec 3.6-liter sedan, LHD): 5,877 produced from 09/1988 through 04/1992
HD92 (ECE-spec 3.6-liter sedan, RHD): 524 produced from 11/1989 through 11/1991
HD93 (NA-spec 3.6-liter sedan, LHD): 1,678 produced from 12/1989 through 04/1993
HD98 (SA-spec 3.6-liter sedan, RHD): 265 produced (assembled from CKD kits) from 9/1990 through 03/1993*
HC91 (ECE-spec 3.8-liter sedan, LHD): 2,676 produced from 12/1991 through 07/1995
HJ91 (ECE-spec 3.8-liter Touring, LHD): 891 produced from 03/1992 through 08/1995
HC92 (ECE-spec 3.8-liter sedan, RHD): 343 produced from 12/1991 through 06/1995
*Dates shown indicate final completion of vehicles assmebled in Rosslyn, South Africa.

Of the 1,678 examples of the E34 M5 produced for North America (1,484 for the USA and 194 for Canada), the following are the production totals for each of the three model years:
1991: 1,296*
1992: 121
1993: 261


That leaves 8,344 s38b36 engines ever made with only 1,678 in north america. No wonder the S38 parts are expensive and harder to find. By comparison there were a total of 12,254 S38s ever made vs 18,843 S14 variations ever made.

Data from M registry https://bmwmregistry.com/registry.php

Here is a compilation of s38 swap builds and info.


Non- M E24 S38B38 swap, active in 2020, https://www.bimmerforums.com/forum/s...assis-d-633CSi

Non-M E36 S38B35 swap, not active, https://www.bimmerforums.com/forum/s...ck-s38-powered

Non-M E30 S38B36 swap, not active, http://www.e30techarchive.com/showth...hp&t=95704.htm

Non-M E30 S38B36 swap, not active, https://www.r3vlimited.com/board/for...ntent?t=191125

Non-M E30 S38B36 swap, not active, https://www.r3vlimited.com/board/for...ng-my-s38-swap as well as https://www.r3vlimited.com/board/for...tecii-s38-swap

Non-M, E30 S38B36 swap, active https://www.r3vlimited.com/board/for...march-16

Datsun 280, S38B35 swap, active now S54, https://www.classiczcars.com/forums/...ge=23#comments

M3, E30, S38B36 swap, not active, https://www.bimmerforums.com/forum/s...-M5-motor-quot

Non-M, E30, S38B36 stroker swap, not active, http://www.e30techarchive.com/showth...hp&t=44067.htm

Non-M E30, S38B36 swap, not active?, https://www.e30.de/fotostory/f02050/f02050.htm

M3, E30, S38B36 swap, not active, https://www.e30.de/fotostory/f00200/f00200.htm

m3, E30, S38B36/8 stroker swap, active, https://s14net.vbulletin.net/forum/s...bas-e30-m3-s38 and https://bringatrailer.com/2016/03/28...d-1988-bmw-m3/

M5 E28, S38B35 stroker turbo, active, https://www.mye28.com/viewtopic.php?t=26880 Lucifer's Hammer

Anri, one of the s38 gurus, https://www.m5board.com/threads/dyno...36-3-6.159417/

Non-M, e36, S38B36 swap, not active, https://www.bimmerforums.com/forum/s...36-sedan/page2

E21, S38B35 swap, active posts in 2019, https://bringatrailer.com/2007/10/29...1-with-m5-35l/

M5 E28, S38b36 swap, https://bringatrailer.com/2014/02/10...d-1988-bmw-m5/

Non-M E34, S38B36 swap, https://bringatrailer.com/2015/09/22...w-e34-touring/

E23, 733 S38b35 swap, https://bringatrailer.com/2014/02/26...1984-bmw-733i/ and https://www.mye28.com/viewtopic.php?t=124140

E9, S38B35 swap, https://bringatrailer.com/2016/09/02...w-3-0cs-coupe/

E9 S38B36 swap https://bringatrailer.com/2014/05/05...72-bmw-3-0csi/

E9 S38B36 swap https://bringatrailer.com/2013/12/04...973-bmw-3-0cs/

Non-M E28, S38b35 swap, not active, https://bringatrailer.com/2015/10/04...988-bmw-535is/

Non-M, E23 M88/3 swap, maybe active, https://www.mye28.com/viewtopic.php?f=7&t=146287

E12 S38B36 swap, stackhouse, https://bringatrailer.com/listing/1980-bmw-528i-5/

Good info for S38 swaps http://www.e30techarchive.com/showth...hp&t=85247.htm

Also a good video of how to remove s38 timing chaing and replace the guides without removing the head https://www.youtube.com/watch?v=kisfxWFLmLA&t

That should satisfy the S38 lover for a minute or two. If you know of any other s38 car swaps, let me know.

[mjweimer]

Great update, I read through the entire thread and love the back story. Awesome to see this getting back on the road.


MJ

[e30m3s54turbo]

Sweet s38.
Im doing a s38 b36 with e28 m5 thermostat housing on my e30. I have drilled two holes for better cooling. I changed the thermo cooling piping to e28 m5 to work with e28 m5 radiator.
I’m going to order a e35 m5 throttle cable. It should work.
The oil cooler housing I changed to AME fitting and 19 row cooler.

[downforce22]

It has been a couple of years and is time for an update. Long story short in 2017 I decided to try and increase my income by buying real estate. I was able to do that through a line of credit on my house but that left me with additional mortgage payments and additional debt on top of those mortgages. I was able to pay down my line of credit, make repairs, and get to a stable place financially last year. However I had picked up ultrarunning as a hobby. In addition to several hour runs on the weekend and week days after work, I would often be too tired to drag myself to work on the car in the garage. In 2019 I ran my first 50 mile race and qualified for the Leadville Trail 100 in August 2020. I decided to accept the entry and bypass the lottery system they normally use.This meant an increase in training mileage and time commitment. Well fast forward to 2020 and a few things happened. First Coronovirus hits with most races being postponed in April. Then I fractured my big toe on a training run with a minimum 4 weeks in a boot. And then ultimately Leadville 100 was cancelled so I had some extra time on my hands. Despite most other work being cancelled, I work in an 'essential' field and still had full time work to balance despite teh fact that I would have preferred to be 'working' from home. (likely working on car projects if I could have or running).

I not only had a full engine swap on my 1991 325ix to do, but also a new lemons build for an m42 powered 1984 318i. The culmination of things brought me back to my projects and ultimately gave me the confidence to start back on the s38 car. I also wanted to drive this car to the 10th anniversary Drive 4 Corners meet. Last year I drove my 318i 318iS.

Starting where the car left off, it has sat without a battery until I could get to it. With winter coming and going I opted to insure and register the car this spring. I was able to get insurance through Grundy after American Collector wouldn't cover me due to my daily being older than 10-15 years old. So here it sat. Over the course of the last 2 years I did a few things here and there but nothing major.

20190907_192954 by tee scz, on Flickr

The springs I had on it raised it a bit but were way too soft for the S38's extra weight. I found these CXRacing coilovers here on R3v and got them for half of list price. They increase the stiffness considerable and should suit the dynamics of the car without allowing it bounce much on the rebound. For the rear spring I ended up going back to the stock ones that came with the car and put the purple vogtlands on the 1991 318is.

https://www.cxracing.com/CO-BMW-E30-1009

Mono-Tube, Top Mount, 32 Step Damper & Ride Height Adjustable

Street Sport Spring Rate: Front 10kg(558 lb/in) / Rear 9kg(502 lb/in)

20190205_195623 by tee scz, on Flickr

You can see a spare diving board cowcatcher in the photo that might be going on the m42 powered track car at some point. But I took the liberty of painting the Jimmy Hill front valance a flat black while it was off. I took the car out of the garage a couple of times but it ultimately had a no start issue that was intermittent. From working on the wiring on my the m42 powered track car, I figured looking at the main relay was a possibility. I had a spare main relay and swapped it and it has started up both times I needed to so that could be the problem.

20190907_183309 by tee scz, on Flickr

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After the no start, I got it running but a lot of hesitation I have had with the car has been an intermittent ticking. It is louder than normal and I ignored it and didn't drive the car until I was ready to dive in. This was earlier this year when I started the car. You can head a loud valve ticking on this video.

Click to play video
20200510_194649 by tee scz, on Flickr

I finally was looking at the situation and decided to get back into the car. When it was idling, I noticed the voltage was at 11.xx. That is weird because I had previously replaced teh voltage regulator in the car and it was a pain due to allen head bolts instead of standard screws. I started small by taking off the MAF and removing the alternator. Well to remove the alternator you have to remove the radiator. I pulled that out and found a couple of things. As it turns out the voltage regulator was in but the spring loaded metal tab that pushes the voltage regulator into the correct position was bent sideways and not riding in the groove that it was supposed to be in. I bet that was the problem. I also noticed an extra wire connected to the engine block from the alternator housing. I had never seen this and wasn't sure what it was for. I ended up taking the spare alternator from the 325ix engine swap I was doing and installing that instead. I found on e28 forums that the e28 alternator has a rubber bushing in the mounting tab to the bracket. The e30 does not and that serves as the engine ground. This original alternator looked a bit crusty so I put it on the shelf for another project.

https://www.mye28.com/viewtopic.php?t=70035

With that resolved and half apart, I got to looking at the H31 Hydroboost system. There is a reservoir for brake fluid and another e28 style reservoir for some special fluid called Pentosin. When I removed the cap, this fluid was black like dirty brake fluid and the reservoir was rusty and dirty. The lines to it had some leaks and this brake fluid was all over the bottom half of the engine. I decided to remove it and replace the lines. In this photo you can see a clear rubber hose on the bottom that I used to extract the fluid and that black fluid was what was in my power steering system. I didn't take many photos of this but used phosphoric acid to clean the metal reservoir to a nice gunmetal silver.

20200618_214816 by tee scz, on Flickr

With that apart, I had come across AngryAssSolutions from a local friend with e34 m5 at a previous drive4corners. They specialize in e34 m5 components and I had been talking to him about how the resonant flap on my car did not operate. He said that the valve diaphragm could have failed and to test it. They also makea replacement actuator that is now NLA by BMW. https://www.angryasssolutions.com/parts I also started reading and found the S38B36 has a separate ECU to control this valve while the later B38 engines have it built into the ECU. I found the control box in the glove box. The way I saw it, there were two possibilities, either the ECU failed, or the diaphagm/vacuum line to it failed. I found replacements on Ebay for $~100 but decided to wait on buying a replacement ECU. What all this meant was the intake had to come off and I started working on the S38 for the first time.

20200625_205515 by tee scz, on Flickr

With the intake off, I could look at the vacuum lines and test the actuator. You can test the actuator by sucking on the hose and if the diaphagm is still good it will operate. The valve is simple as a electronically activated but pneumatically actuated valve. It runs off throttle position, engine vacuum an engine RPM but has a startup function at engine start. Without the intake there is much more room to work. I got to looking and noticed a few things. The oil filter originally came with oil cooler lines but they have been ported off; likely to save space. There was also a crappy copper pipe in the cooling system to the heater core. I got rid of that and replaced it with a simple plastic elbow. The fuel filter looked old and I found a replacement for $10 so I cut the old one up and ordered the new one. It didn't look bad but new can't hurt.

20200701_180659 by tee scz, on Flickr

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The Resonant flap has some vacuum line, a check valve, and a vacuum reservoir. The vacuum lines were tired and cracking. Check valve seemed fine. The idle lines were a bit tired so I ordered 2 new hoses at a depressing $100 for 2 hoses.

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It was around this time I started compiling S38 specific data. It appears some of this stuff is disappearing and so I have been collecting it to make sure I have it if needed. Here is a tech data sheet from AAS about the resonant flap. Also a better view of the midrange torque you get from the flap and the ECU wiring diagram so I could determine how the thing worked.

https://static1.squarespace.com/stat...h+2020_1.1.pdf

Screenshot_20200701-225444_Drive by tee scz, on Flickr

Screenshot_20200701-230330_Drive by tee scz, on Flickr

After studying the diagram above, I realized a third possibility for the resonant flap was the solenoid. I found a thread on m5 board where the solenoid was updated and had different connectors. Well I had seen this part before on the firewall of my euro motronic 1.0 325iX (11/1985 build with 885 head and 073 ecu and high compression pistons). I went and grabbed it and it looked identical. The only difference was one digit in the part number. I also had seen it on the firewall of the 1984 318i with vacuum advance that is the base for my lemons car. Man how ironic that this stuff has some overlap from when I was doing the wiring on that car this spring. I took both parts and tested with 12 v. The relay from the s38 just arc'd as if grounded and the other one from the 325ix clicked correctly. We might have just solved out midrange torque problem.

20200701_223240 by tee scz, on Flickr

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I got it back together and the valve cycles at startup!

20200712_154442 by tee scz, on Flickr

While I had it apart I fixed up the throttle bracket mount that looked like crap. I sanded it down and now its a cool gunmetal.

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I took the car around the block to test the resonant flap with it all assembled when the throttle stuck open. during second gear.

https://www.youtube.com/watch?v=WoXmPB4KqXM

It turned out to be the throttle linkage sticking on the fuel rail.

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Here it is stuck in the open position.

20200712_215323 by tee scz, on Flickr

Remember my injector change? Well it appears they are the same.

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After pulling the whole fuel rail, I found one injector that appears to not be seated correctly in the rail. I'm not sure if the o ring was the wrong size or maybe it wasn't lined up right when I installed it, but the cap on the new injector was slightly cockeyed. After replacing the stock injectors back in the engine, I made sure to push the rail away from the linkage and the linkage now cleared the fuel rail.

With that resolved, I moved back to the cylinder head and felt confident enough about moving forward with a valve adjustment. The engine did not have the tick during cranking, and it seems to be related to the valve train as it follows the rpm of the engine. The main resource for this appears to have gone missing so I found a couple others ones to walk through the process. Little known fact, the euro s50 has the same bucket and shim design as the s14, and s38. After more research, I found a thread on m5board about the valve adjustment process and it talks about the owner hearing a noisy valve at 0.41". If I had a valve out of spec, maybe that could be the noise. I had the special tool for depressing the cam buckets and some shims and set to work. Also note to rotate the crank, I had to remove the radiator again due to clearance and my skid plate. Pretty annoying considering all you are doing is rotating the engine with a socket and breaker bar.

https://www.1988bmwm5.com/perform-s38-valve-adjustment/

https://translate.google.com/transla...search&pto=aue

I was expecting 6 to 10 shims not 17. Upon reflection the shims have never been done since so it's almost 4 inspection cycles overdue.

Most of the cylinders had opened up to .35, I was correct in predicting a big correction on one cylinder, I thought it would be cylinder 5 but it was cylinder 6 where Exhaust 1 had opened up to 0.41, this was the ticking sound I heard. Some wear marks on the cam lobe for cyl 6 but no scuffing or scratching. The noise disappeared with a new shim.

The most shims common shims used in going into the engine in GA25324 were 3.75 and 3.85, lots of 3.70 shims came out which is good news for GA25331 (bluebiturbo's M5).

Engine runs much smoother and has picked up bottom end torque and response. It absolutely screams now at 7,000rpm. Smoother all the way through the rev range. It's early days but the engine also appears to be running 5 to 10 deg cooler on oil temp, I'll report back on this in a few days. The engine passed the ///Marlboro cigarette packet test where the cig packet can sit balanced near the cam cover vent without vibrating off or falling over.

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I didn't have a 0.013 or 0.011" feeler gauge so those 0.14 may be right at 0.013". Spec is 0.011-0.013" on a cold engine. As you can see cylinder 5 intake was way off at 0.018" which equates to like 0.46 mm or something which is more than the post from Asean Aero above. I changed those shims and ordered some new ones since I didn't have thick enough shims to get within tolerance. In the process of changing cylinder 6 exhaust, the replacement shim was in but wouldn't allow the bucket to spin even with the cam lobes pointing up. I checked it and ultimately found the shim to be cockeyed in place. I might throw that one in the trash and put the original shim back in until I receive the thicker shims. See below how it is cockeyed here.

20200715_203338 by tee scz, on Flickr

The last thing I found is that since this car runs the s38b35 thermostat housing, some parts distributors have the wrong information on the thermostat housing. I ordered the cheap oem replacement thermostat instead of the true 737 part and it turns out the thermostat is too small and has the wrong lip on the edge of it. The thermostat that came out obviously fit, so I decided to use the new gasket and test the old thermostat still worked. Note the thermostat has a hole drilled in it so that either helps with cooling, or it was done to help bleed the system. I opted for the old boiling water test to see if I needed to order the $50 thermostat or if this one was still good.

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I also took a look at the e24 M6 for comparison. It runs the same H31 Hydroboost system and has some similarities to the b36 engine. I was checking out the thermostat housing among other things too. Fun fact, the e24 M6 has a WBA VIN number, not the 'Motorsport' WBS VIN number that started on the e30 m3. I found this interesting.

20200718_164844 by tee scz, on Flickr

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the first 3 character represents different manufacturer division or group at BMW, not specific assembly plants. All M car is now assembled in the same plants as the regular BMW models.

Here is a quick BMW VIN decoding guide:

(example VIN) 'WBA' 'AA13' '1' '4' 'L' 'A' 'E57862'

first 3 characters = Mfg Code
WBA = BMW AG, Munich, West Germany
WBS = BMW Motorsport GMBH, Munich
4US = BMW Manu. Corp., Spartanburg, SC, USA

next 4 characters = Vehicle Description Section

And finally some pictures of the fuel rail clearing correctly. It is still tight but works now.

20200721_205206 by tee scz, on Flickr

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20200721_205826 by tee scz, on Flickr

20200721_205809 by tee scz, on Flickr

In the mean time I am waiting for the valve shims to finish my valve adjustment. To make progress while I wait, I started looking at the cooling system in greater detail. The s14 and other engines of the era use a 1.4 bar coolant reservoir cap. I am running the e30 m3 reservoir for now, so I am limited to that being the max rating on the 180* twist style cap. The later reservoirs like the m20 res and m42 318i reservoir have full twist on caps with the m42 rated to 2 bar. I looked the e34 m5 and it runs a 2 bar cap. This may be part of my problems with the cooling system., where my 1.4 bar cap is reducing cooling. A higher rated cap will increase pressure and increase cooling capacity of the engine by allowing a higher boiling point. This prevents air bubbles from forming in the coolant at hot spots along the head. For reference, I was planning to try water wetter which does the same thing. I am wondering if this would help keep the engine cooler by increasing the amount of heat the coolant can carry that makes its way to the radiator . Here is a great pdf on pressure and mixture ratios of coolant and water.

https://durathermfluids.com/pdf/tech...ling-point.pdf

[kronus]

bump for updates, I like this car

[jeenyus]

I idea that you can use your identical twin as a type of POA is just wonderful to me.

[The_Lope7]

Just read through the whole thread what an awesome story. Any updates?

[2mAn]

This is such an awesome car... when will it be "done" because they are never actually done

[Jean]

Such a cool find and story ! Glad you are giving her another chance at life ! Thumbs up !

[ThatOneEuroE30]

Odd they drilled that in. On my 89 i got a state issued vin and it took all of two days and was a sticker. It will come off and be saved when the car gets painted but not like i will ever need it again.