M30 OEM Turbo project

[CorvallisBMW]

I just realized your running AC. How come? Would removing it make life much easier?

Yes I am keeping AC. It's not that I really need it, I just want it. It's still the original R12 system and blows ice cold, so I'm willing to go through a bit more work to keep it functional. The compressor and lines definitely get in the way of several things including the piping between the turbo and IC, and the exhaust manifold near the #1 cylinder. In fact I may need to get a new suction line fab'd up at an AC shop to clear the manifold, as even holding it way out of position with zip ties doesn't create enough clearance.

And of course AC adds extra load to the cooling system, which is already tricky on m30 swaps, and even more so on turbo cars... I guess I'm just a gluten for punishment :)

[ThatOneEuroE30]

Yes I am keeping AC. It's not that I really need it, I just want it. It's still the original R12 system and blows ice cold, so I'm willing to go through a bit more work to keep it functional. The compressor and lines definitely get in the way of several things including the piping between the turbo and IC, and the exhaust manifold near the #1 cylinder. In fact I may need to get a new suction line fab'd up at an AC shop to clear the manifold, as even holding it way out of position with zip ties doesn't create enough clearance.

And of course AC adds extra load to the cooling system, which is already tricky on m30 swaps, and even more so on turbo cars... I guess I'm just a gluten for punishment :)

Ah Well good luck my friend.

[CorvallisBMW]

Who has two thumbs and likes progress? This guy.

One of the issues with the stock intake tubing was the way it was shaped. It bent inwards towards the motor and would not allow the stock elbow to fit where I needed it in the e30 bay. You can see how it's angled in.




I knew I needed it to point both more towards the fender and be taller. So, more choppy choppy.






I had to makes some calls and look around for a shop that could do custom aluminum pipe welding. The stock tube is about 2-7/8", not 3", so it wasn't as easy as just adding some off-the-shelf bits. I finally found a place called Accurweld over in Washougal, WA. It took him a bit longer than he originally indicated, but the work isn't bad. I had 1.5" of length added to the lower/turbo end and 4" added to the upper end.




One end looked really good with nice, smooth transitions




But the other end wasn't quite as pretty. I'll need to break out my Dremel and smooth that lip a bit.




Once installed, it fit perfect




Now with the stock elbow fits on, along with the MAF and a 60* silicone elbow for the (as yet to be determined) air filter




With the intercooler in place, it's really coming together! I tried to buy the factory 745i breather tube, but it came back as "blocked" in North America. Weirdest thing ever, I've never heard of a part being blocked. Oh well, some 3/4" oil-resistant Buna-N tube worked OK with a couple of the stock 90* elbows.

[TimeMachinE30]

Wow. Moving rather quickly. Looks quality.

[CorvallisBMW]

Acutally I'm surprised by how fast it's going, I was expecting a bit more fabrication to be required.

There's still lots to do, but hopefully most of the big stuff is nearing completion. Most of what is left is sort of medium-difficulty.

Medium-difficulty shit still on the to-do list:
-Get new passenger-side motor mount arm from Otis
-Get new reinforced subframe back from welder, paint it
-Add oil feed line
-Add oil drain fitting to spare pan, install
-Send out all hot-side exhaust components for ceramic coating
-Send Intercooler out for heat-rejection coating
-Fab up mounts for IC
-Install 10" IC fan
-Install charge piping between turbo and IC
-Figure out gauge setup (boost, A/F, oil temp/pres, etc)
-Find Miller tune, purchase matching injectors
-Find air filter that fits in tiny space
-Replace valve cover gasket and guibo

[ThatOneEuroE30]

Acutally I'm surprised by how fast it's going, I was expecting a bit more fabrication to be required.

There's still lots to do, but hopefully most of the big stuff is nearing completion. Most of what is left is sort of medium-difficulty.

Medium-difficulty shit still on the to-do list:
-Get new passenger-side motor mount arm from Otis
-Get new reinforced subframe back from welder, paint it
-Add oil feed line
-Add oil drain fitting to spare pan, install
-Send out all hot-side exhaust components for ceramic coating
-Send Intercooler out for heat-rejection coating
-Fab up mounts for IC
-Install 10" IC fan
-Install charge piping between turbo and IC
-Figure out gauge setup (boost, A/F, oil temp/pres, etc)
-Find Miller tune, purchase matching injectors
-Find air filter that fits in tiny space
-Replace valve cover gasket and guibo

Not to much left. I suspect you'll be done rather quick.

[SkiFree]

All euro parts are now blanket blocked from bmwna (this happened about 2 months ago) .... I learned the hard way.

[ThatOneEuroE30]

All euro parts are now blanket blocked from bmwna (this happened about 2 months ago) .... I learned the hard way.

What do you mean blocked? Haven't had a problem ordering euro parts.

[ak-]

Looking good.
Please don't run your breather tube that way though. I've had nothing but trouble in the past having it like that when I first turbo'd my m20 and had a bunch of trouble doing it this way on my rebuilt turbo m20 with even 2 breathers on the valve cover.
It throws oil into your charge piping and lowers your octane rating with the oil/vapor getting into the cylinders.
While on the dyno tuning, I was having all sorts of trouble until I vented it to atmosphere which resulted in taking out a lot of fuel from my table because the car now ran super rich - showing that the amount of fuel needed to cool things down was a result of that oil vapor getting into the system lowering the octane rating.

I just don't want you to go through what I did. I'm starting to think I ruined my first motor gradually over time because of this.

[CorvallisBMW]

Looking good.
Please don't run your breather tube that way though. I've had nothing but trouble in the past having it like that when I first turbo'd my m20 and had a bunch of trouble doing it this way on my rebuilt turbo m20 with even 2 breathers on the valve cover.
It throws oil into your charge piping and lowers your octane rating with the oil/vapor getting into the cylinders.
While on the dyno tuning, I was having all sorts of trouble until I vented it to atmosphere which resulted in taking out a lot of fuel from my table because the car now ran super rich - showing that the amount of fuel needed to cool things down was a result of that oil vapor getting into the system lowering the octane rating.

I just don't want you to go through what I did. I'm starting to think I ruined my first motor gradually over time because of this.

Huh, I wouldn't have guessed that to be the case, but it's good to hear from first hand experience.

Really all I'm doing is copying the factory setup. From the factory it was routed just like this, though I did contemplate adding an oil catch can to prevent any nastiness from making it's way back in the the intake. How much boost were you running? I'm only doing like 6-8 lbs.

Maybe I'll vent to atmo, I guess I'd just need a catch can or filter of some kind that I can hide in an inconspicuous place. I really don't want a ricey eBay breather filter on top of the valve cover.

[ak-]

Huh, I wouldn't have guessed that to be the case, but it's good to hear from first hand experience.

Really all I'm doing is copying the factory setup. From the factory it was routed just like this, though I did contemplate adding an oil catch can to prevent any nastiness from making it's way back in the the intake. How much boost were you running? I'm only doing like 6-8 lbs.

Maybe I'll vent to atmo, I guess I'd just need a catch can or filter of some kind that I can hide in an inconspicuous place. I really don't want a ricey eBay breather filter on top of the valve cover.

Yeah man, I was surprised that my setup acted the way it did.
First I had a catch can in line from the breather to the turbo intake elbow - same result.
Then no catch can, with a line from breather to turbo intake elbow, thinking it was restricting flow/pressurizing the crank case - same result.

Ended up venting the catch can to atmosphere and everything was dandy from there on with the exception of having to remove fuel from my tune because it ran rich now since oil vapors weren't being introduced in the cylinders.
This was all tested on 11psi, which is going to have more blow by then your m30 on 6-8psi (I think? Engine liter/efficiency play a role here?), so maybe your results won't be as extreme, but I don't want any kind of oil vapor in my system anymore - just too big of a variable on finicky turbo cars.
Idk how other cars do it or maybe I don't fully understand the concept yet of pulling vacuum into your breather.

Did factory have a catch-can, cyclone-separator, or check valve in between?

[CorvallisBMW]

Yeah man, I was surprised that my setup acted the way it did.
First I had a catch can in line from the breather to the turbo intake elbow - same result.
Then no catch can, with a line from breather to turbo intake elbow, thinking it was restricting flow/pressurizing the crank case - same result.

Ended up venting the catch can to atmosphere and everything was dandy from there on with the exception of having to remove fuel from my tune because it ran rich now since oil vapors weren't being introduced in the cylinders.
This was all tested on 11psi, which is going to have more blow by then your m30 on 6-8psi (I think? Engine liter/efficiency play a role here?), so maybe your results won't be as extreme, but I don't want any kind of oil vapor in my system anymore - just too big of a variable on finicky turbo cars.
Idk how other cars do it or maybe I don't fully understand the concept yet of pulling vacuum into your breather.

Did factory have a catch-can, cyclone-separator, or check valve in between?

Again, good to know. Maybe I'll ditch this idea and just vent to atmo then.

AFAIK the stock system had no kind of catch system. You can hee it here, parts #6, 8 and 9.





So I tried to look more closely at the oil feed line today. It's a completely rigid tube, absolutely no flexibility or unions. It's supposed to go from the oil filter housing to the turbo... pretty straightforward.




Unfortunately it hugs the block really closely which means to run it I'd need to pull out the radiator, alternator, and most of the front of the engine. I hate, hate, hate bleeding the coolant system on this thing so I'd like to avoid that, but... shit. Looks like my choice is to either create my own feed line using a tee off the pressure sensor on the back of the head, or pull stuff apart and use the stock line. I'm not sure what's best so I'm going to sit on it for a while, do some thinking.

[AWDBOB]

Me thinks this is a badass project, I've always wanted to do something of the sort.

Side note: I agree about the VTA vs recirc that ak was saying. I've always had much better luck running VTA for reasons stated above. Do you know if you need to recirc for proper vacuum or no?

[ak-]

Best of luck

[CorvallisBMW]

Me thinks this is a badass project, I've always wanted to do something of the sort.

Side note: I agree about the VTA vs recirc that ak was saying. I've always had much better luck running VTA for reasons stated above. Do you know if you need to recirc for proper vacuum or no?

That's +2 on the VTA idea, sound like a plan to me! I don't know about vacuum on turbo cars, but I found this excellent article om MotoIQ regarding NA cars: http://www.motoiq.com/MagazineArticl...A-Edition.aspx