'94 E34 Touring slicktop, forged M50B30 powered, S362SX-E boosted, daily driven

[varg]

The vanos rebuild did effectively nothing. I don't know why it's malfunctioning, so I disabled vanos and definitely gained some power though the drop in mid range torque is noticeable. I bet I picked up at least half a second on my 60-130 time with this change but I haven't had the opportunity to re-test. By the next time I do it'll probably also be on significantly more boost. As is right now it would probably put car lengths on a mustang gt (12.2-12.3s 60-130), at 20psi it should keep up with an RS6 (10.5s). I'm using 60-130 as a performance benchmark because there are no drag strips here and I don't want to risk breaking my driveshaft or axles with aggressive launches.

I'm also having AC problems. I initially thought this was because my custom lines were still too close to the downpipe so I re-did them when the engine was out for the second time, and it still happens. With the car cold or on the highway, the AC works, it blows cold even at idle. Very cold on the highway. Once up to temp the AC will turn off when I'm in traffic for more than a few minutes. And I mean turn off, the snowflake and recirc button lights go out, it's not just getting warm. If I unplug the IHKR and plug it back in it blows cold again. I thought it was due to the under hood temps near the exhaust getting too high and overheating the lines. This would cause a high pressure cutout but cooling the lines and condenser with a hose in my driveway didn't cause the AC to turn back on and I can't put the gauges on the system with the car hot because the service ports are too close to the exhaust. It's possible that there's a cooldown timer in the IHKR logic and once the HP switch is tripped the AC refuses to turn on again for a period of time, but I don't know. There's next to no information available about IHKR function and repair, only IHKA. I am not converting to IHKA. I re-did some solder joints but the board is conformally coated with an epoxy resin, and I did some work to the controls; cleaning the temp sensor, re-soldering the board, but it didn't solve the problem.

My spare vanos was in great condition. I almost felt bad rebuilding it. Oh well. I cleaned it up inside and out and rebuilt it only to have no change.



This is my next step to trying to solve the AC issue as well as my problem of melting windshield washer line tees, installing a loud 5.2" Spal fan forcing 300ish CFM of outside air into the hot side of the engine bay. There will be a baffle in front of it so it pulls cool air from the front end instead of just recirculating hot air. I was going to use a bilge blower but it was even louder and sounded like a hair dryer. Fingers crossed.


Soon I'm going to have to wire a high current relay straight between the battery and the fuel pump, using the stock wiring only to trigger the relay. My fuel pump is pushing the limits of the stock wiring as you can see by the fuse temperature relative to others in the box and I bet that will cost me some fuel flow when I turn the boost up more. As a side note, I love this thermal camera.


It still burns oil (and leaks). I love this car and it is fast but it sucks it gets a lot of attention, people frequently compliment it or recall stories about their own old BMWs, then it smokes and looks like a total piece of junk.

[varg]

Thanks, as for residual oil burning off from something, not a chance. I've been daily driving this thing and my commute is 33mi each way, plenty of time for oil to burn off. I'm convinced that there's something wrong with the bottom end. Either the clearances are too large after the re-hone or the oil rings are for some reason not doing their job well. It has good compression somehow even though it smokes like a piece of crap, which really pisses me off because my my 270,000mi+ abused stock engine didn't produce a hint of smoke.

I've also been tuning, fixing surface rust, and breaking down. I think it was the dumbest breakdown, the ignition switch connector was loose but was so tucked away that I didn't diagnose it as such when it first cut out. It has been like this for years now and didn't make a peep until early February... At least my AAA tow arrived in under 2hr. I think I've done pretty well, I've been DDing heavily modified old cars for over 13 years and I haven't needed a tow since late 2010. What happened was that it the car started cutting out momentarily and unpredictably (once or twice per day at first) after doing my first real benchmarking exercise, which kind of threw me off. Then it decided it didn't want to run for more than a random amount of time, and wouldn't restart for another random amount of time. Instead of limping home from shutoff to shuttoff I called for the tow. As for that 60-130, the car did it in 12.66s. That's .3-.4s off of a new 6 speed mustang GT's time, and the car is pretty unhappy from a power standpoint. It is on my base ignition map, with a 200kPa boost target (oscillating response) and as I found out looking at the logs again because of the strange shape of my boost VE table, with a sluggish VANOS unit. VANOS is very slow to respond, around 1.5s each way during transients, and revving out it only backs off a couple of degrees before I shift and it re-engages. It will be interesting seeing the difference in performance with a rebuilt unit because the cam refusing to retard has to be costing me big after 5,000rpm.

This was a pain. I had to cut the crumbling gap filler trim off with a hobby knife then sand the surface rust where it was trapping dirt and scouring the paint.



Another E34 design flaw is these inane lower door edges. You can tell the E34 is where BMW started to lose their touch with building long lasting, sensibly designed cars. Necking the door down and putting an expensive piece of rubber reinforced trim on it? Come on. They trap dirt and moisture and cause rust. Stupid.



Night shot of the fleet.



Self explanatory



The center graph shows the VANOS solenoid turning off and the cam timing (yellow) barely budging before my shift point. Also notice my MAT in the lower graph, this turbo and intercooler are playing well together, and the plunging VE value, which is something I'd expect with the cam staying advanced all the way to redline.


I just wish the brand new engine didn't burn oil, that is not going to stop bothering me.

[Northern]

It's been a whole page since I've seen this car, and it's seen a lot of work.

Car sounds great. Hopefully the exhaust smoke is just residual oil that needs to gradually burn off?

Wishing you luck with that ProVent. Mine let oil into the intake in the first few days it was installed so I just vent to atmosphere now.

[Dj Buttchug]

Dude that thing sounds great!

[varg]

Quick video update. A short clip so you can hear what it sounds like on low (11psi) boost. Eventually I'll get some more clips as I continue to turn the boost up. I am ok with how it sounds, it could be better, but it could also be worse. It is nice that it isn't raspy or overly loud. I6s, especially 24V BMWs in my opinion, tend to sound absolutely terrible. The post E90 M3/4s for example, sound like total ass. I don't like stand rasp and excessive loudness, a good exhaust sound is sonorous or wailing, but never raspy or harsh. I was afraid that the large pipe diameter and straight through mufflers would work against me, but it turned out sounding like a 24V version of my E30, which is basically what I wanted. Makes sense since the exhaust configuration is very similar, just 1/2" larger. It would probably sound better if the manifold was equal length and 6-1 instead of unequal length 6-2-1, but packaging being what it is, I don't know if that would be doable.

Right now I'm fighting oil cap leaks and doing repairs such as sanding rust spots from paint chips and covering them up. It still needs the rear bushings and brake lines upgraded too. Right now the right rear tire rubs on the fender but the left doesn't, because the subframe is shifting a bit under squat.

Well at least the oil leaking part is gone now. Nice bit of progress to keep you sane. I think I may have a drivers side lower door trim piece for you. I will check in my stuff this weekend. Looking forward for more info. I also want to see what settings you are running for idle control. min/max clamp and start up offset settings.

They're nothing special, and my cranking/startup duty cycles are probably of no use to you because I have a bigger engine and an adjusted throttle body stop. I also idle at 1,000rpm hot to keep the transmission and clutch noise to a minimum, reduce the chances of stalling when electric and AC load increases, and keep the vibration in the cabin to a minimum. It's a totally different animal with a clutch setup like mine and solid UHMW engine mounts. I actually have the replacement door bottom trim pieces I need, I just haven't installed them yet because I need to sand the surface rust off where they rubbed the paint off of the body and paint over it.

[Dj Buttchug]

Well at least the oil leaking part is gone now. Nice bit of progress to keep you sane. I think Imay have a drivers side lower door trim piece for you. I will check in my stuff this weekend. Looking forward for more info. I also want to see what settings you are running for idle control. min/max clamp and start up offset settings.

[varg]

Back to daily driving my wagon, and enjoying it a little more. The new turbo spools faster, in the closest I got to an AB comparison I went from, during 2nd gear pulls, 175kPa by 5650rpm with the S366, to 175kPa by 5300rpm with the S362. Switching to closed loop boost control I hit 175kPa by 4900rpm, holding that wastegate closed during spool really does make a big difference. My boost control isn't perfectly tuned now, but I've had some other issues to chase down. I'm looking forward to actually doing some performance tuning and logging so I can start seeing performance progress in numbers. Timed/logged 3rd gear pulls are a favorite of mine for testing, and I'll eventually do some 60-130 times.



On to the issues.

I had a strange failure, the brand new clutch master cylinder feed line I bought, genuine BMW from FCP, was leaking. I don't know where it was leaking from, it seemed like the whole thing was weeping fluid. It made a total mess, got brake fluid on my strut tower and subframe, ran down into the cabin. It's a complete pain in the ass to replace in an E34, way worse than an E30. It was impossible for me to get the grommet back into the firewall hole. I installed the one that failed with the engine and master cylinder out of the car and it was possible. so I'm figuring out what I'll do with that.




Dj Buttchug proved prophetic here. The new turbo started leaking oil out of the turbine after I put a commute on it. It was so bad it was dripping down out of the CHRA and onto the turbine housing. I was confused because the S366 didn't do this, figured it couldn't be the drain flange, but it was my only shot. I pulled the drain flange and replaced it with this Cummins truck drain I bought on Amazon. It is much larger, 18mm ID, the aluminum flange was just over 12mm, way too small... So I replaced it, I crammed a 3/4" hose onto the end of the drain, tightened it down, and adapted it down to the 5/8" of the 10AN on the pan.




It's not pretty, but the turbo stopped leaking. I had hope that this would stop the exhaust smoke, but it didn't. I couldn't see the drain still being an issue, and I want a cleaner solution than this, but I can't exactly replace the 10AN in the pan with a 12AN. I'm going to have to step down from the 3/4" hose to 10AN somehow, maybe a fitting that is 10AN threaded with a 3/4" barb.




Next, to cure my steering wheel vibration under braking at around 50mph I replaced my control and thrust arms, this also improved front end feel and handling. I am not looking forward to replacing the bushings in the rear.




A provent clone AOS install is in the works next. Turns out a 3/4" hose shoved into the valve cover breather port fits perfectly. I'm going to try just running this larger breather and draining the oil from it. Whether I'll eventually vent into the turbo inlet and use a vacuum line with a check valve to pull some vacuum on the crankcase, I don't know. I would prefer not to. The exhaust still smokes with a breather style oil cap so I don't think it's possible that crankcase pressure is responsible for the smoke.



To be continued.

[Dj Buttchug]

Nice progress. Not sure if my issue is comparable but your smoking symptoms seem somewhat similar to mine. Oil in the combustion chamber obviously rules out turbo oiling issues.
I have been battling this issue on my engine as well for the past two to three months with several changes in the turbo oiling system and no success in fixing until this weekend. I am pulling oil from the oil plug at the rear of the cylinder head. I don't believe the location of the oil feed is relevant, but pressure and flow could be different if you are pulling from the filter housing or another location close to the oil pump. Anyway, here what I've been dealing with.

At engine idle, low load or lower RPM rev range there is no smoke in the exhaust. But as engine speed and oil pressure increases things change. If I enter the 5k + engine speed range or quicky stab the throttle and let off, engine goes into overrun (no smoke yet) Right when we reach idle speed again, I get a lovely sizeable puff of bluish smoke. It would happen every time. My engine doesnt smoke on startup only coming off rev.

There was no evidence of oil in the turbine housing at all. No wetness or dark markings. Nothing.

My old oiling system was as follows. -4AN line to a standard oil restrictor that came with my turbo. I believe the hole sizing was .065 or larger. This caught my eye but I installed it anyways. Still no changes in smoking after moving from a journal bearing turbo to a BB unit.

To fix the issue I ended up switching to a -3AN line, .035 restrictor AND creating a restrictor at the port on the back of the cylinder head. I Tig welded the M10x1.0 shut on the cylinder head side and redrilled the inner diameter smaller to reduce overall volume in the line. After doing this I tested to confirm the turbo is still getting sufficient oil flow through a clear temporary drain tube. After I did this mod, the smoke is gone. I can bounce the engine off redline and it still will not smoke.

My car is still in the air, so I have not yet been able to test on the road, but I think reducing the amount of oil in the line has fixed the problem. My theory is the volume of oil being delivered to the CHRA is too high (even when properly restricted) and was just enough to spill over into the exhaust turbine... ??? Hard to know for sure. I should also note I did have a small bit of oil in my compressor housing as well (very light film that would creep from the compressor blades) This symptom is now gone as well.

I should mention as well that I tried 4 different oil drain setups, modified the drain tube inner diameter to make sure oil could escape the center cartridge quickly and tested several settings of CHRA clocking trying to find the best setup for oil flow. I ended up using a magnetic level to ensure my turbo is clocked correctly. Being you are top mount I think there is less need for this but worth adding for info purposes.


Hope you get it figured out and looking forward to how the new turbo spools up.

[varg]

I've been daily driving the car for a while now and have about 1,300mi on the engine. The smoking issue is bothering me, new valve seals didn't fix it. I replaced them after spotting a drop of oil running down a cylinder wall and oil on the combustion chamber and valves while borescoping. I noted nothing wrong with the seals I removed and it proved to be a total waste of time replacing them. I've performed leakdown test but unfortunately my old harbor freight leakdown tester has poor resolution because of its oversized orifice so all it told me was that all cylinders are the same within its resolution. Currently I'm unsure of what I will do about this because it's hard to gauge the oil consumption. My valve cover leaks persistently, having been ruined by an incompetent powdercoat shop, it does not seal even with RTV on both sides of the valve cover gasket and leaks at the fill cap. I'm now seeking a replacement valve cover that won't need refinishing like my spare does, unfortunately they are around $400 new if available at all. There's also a lot of blow-by but since this is the first new all forged engine with big ring gaps I've had my hands on (0.018" gaps), I don't know what is normal.

My 3D printed valve spring compressor


Plugs showing evidence of being rich (as expected) and oil burn on 3 & 5...



After datalogging as I progressively turned the boost up to around 12psi I decided the S366 is too big, and that the possibility of 700whp+ was not worth the lag, so I bought an S362SXE on black friday sale to replace my S366. I'm expecting that going from a 66/91.4mm compressor to a 61.4/83.5mm compressor, and from an 80mm turbine to a 76mm turbine, I will gain valuable boost response, and still be able to do 600whp+. Below is a piece of a log from a 3rd gear pull, as you can see my boost is still building at 5,000rpm (the vertical line marker). Of course I didn't know when I ordered the turbo that the valve seals wouldn't stop the oil burn, this car may never even make 600whp with that issue.



The S362 and S366 compared. They are the same size on the outside but different internally.





Condor speed shop fall meet


This has continued to be a frustrating project, it's not at all rewarding having the money to do everything right instead of cobbling together junkyard/used parts, when having more issues than I ever had in my shoestring budget builds like my Volvo and my E30. More on that to come.

[varg]

The timing of the smoke, mostly when I stab the throttle for a quick rev, taking off from a stop, and sometimes on startup, doesn't point to typical turbo smoke.There was also no oil residue in my throttle body. I immediately started checking other things honestly because I've never had any smoke from a turbo on the E30 with the nearly identical 4AN feed and 10AN return to pan, even with Turbonetics turbos, which are arguably lower quality than Borg Warner. I'm planning to have a friend who is also a car enthusiast and a mechanic follow me this weekend and tell me when it smokes, but so far I've had no evidence that it smokes on overrun or at WOT, other than what sounded like the thin dark smoke typical to a turbo car when my wife described it to me while following.

[Dj Buttchug]

Is there any evidence of oil getting out of the turbo housing? Oil restrictor correct in oil line? Maybe you've checked all this already just thinking out loud. I would assume you have proper oil drainage flow from the turbo housing back to the oil pan. I'm wondering if maybe the oil burning is coming from the turbo and in fact is not the stem seals.

*edit*
Re read dripping found in borescope... 650 miles is a pretty good amount. Might not be to terrible to do seals if you can pressurize the combustion chamber to hold the valves up.

[Digitalwave]

Hopefully the smoke is something relatively simple like the valve seals.

[varg]

It's back on the road now and I'm driving at 7psi of boost, tuning as I go. I've put 650mi on the new engine at this point and it runs well, sounds pretty good, and attracts a lot of attention at cars and coffee compared to the E30. It's not all good though. There is a smoking issue I'm trying to diagnose. I borescoped this week after doing a leakdown test (inconclusive because the old HF leakdown tester has an oversized orifice) and found a drip of oil going down the #2 cylinder wall and oily looking CC and valves. I didn't see oil on the intake side with the borescope through the injector ports so it may be exhaust side. This points to a valve seal issue imo, and I'm ordering new seals. Valve seals on a 24V engine in the car will be a pain in the ass, I put new seals in the head before the first build to avoid just this. I either screwed them up (don't see how, I've done it before and it is a simple job) or they were faulty. I'm hoping the seals fix the smoke and consumption so I can work on turning up the boost. The leakdown test showed consistent results across all cylinders though, a fair amount of air came out of the breather hose for all of them, I'm unsure how much is normal for a forged engine with big ring gaps as I've never had anything but frankensteins and old OEM engines. The engine was not cold, but it had cooled for an hour or so before I started the testing. It is a pain to get this car to TDC, it's impossible to see the timing marks from the top, I have to go under the car and stick a mirror up between the radiator fans and crank pulleys then shine a light up to see the marks. I put blue paint pen marks on the trigger wheel that line up with a fin on the oil pan so I can do it from the bottom in the future.

Cars and Coffee 10-15



The ECU box/harness heat shield I added shortly after the turbo heat shield.

Glad to see this back up and going forward. Keep after it! The last we read on this thread made me sad :(

Well done! I have been patiently waiting for an update. Nice to see things are looking up.

Thanks guys, the issues I had took the wind out of my sails on this build, it went from a hobby experience that taught me TIG welding to a chore, and with the E30 needing some repairs pressure was on to have a driveable wagon.

VARG nice wagon! Here’s some food for thought the machine shop I use specialize in big American iron from N/A street cars to NHRA alcohol burners. When I take a block and pistons to them they ask this,

N/A only
N/A with juice ( NOS)
FI only
FI with juice

All versions get a different piston ring end gap stack for the same bore based on piston top / ring temp. I only built N A versions, but he busts me every time I come thru the door.

Thanks. I gapped the rings per the sheet that came with the pistons. They recommend 0.005-0.0055" per inch of bore for the compression ring in for high hp turbo engines, so I gapped to 0.018". Regardless, I don't think that my ring installation caused the scoring because of the lack of scratches when I turned the engine over by hand before installing it, I think debris from the plug wells or intake (which was still pretty crusty in some spots when I cleaned it before the most recent assembly) caused the issue.

[PEZ2]

VARG nice wagon! Here’s some food for thought the machine shop I use specialize in big American iron from N/A street cars to NHRA alcohol burners. When I take a block and pistons to them they ask this,

N/A only
N/A with juice ( NOS)
FI only
FI with juice

All versions get a different piston ring end gap stack for the same bore based on piston top / ring temp. I only built N A versions, but he busts me every time I come thru the door.

[Dj Buttchug]

Well done! I have been patiently waiting for an update. Nice to see things are looking up.