Das Beast: My E30 track / street build

[dvallis]

I tore down the turbo today. Found the problem. Turbo turbine and compressor wheels are supposed to be connected.



And here's the root cause. A tiny scrap of plastic was firmly wedged in the 0.060" turbo oil feed restrictor. All I can say is WTF? Our turbo oil feed is off the sandwich plate, which should be post filter, unless someone can tell me otherwise.

Combined with oil starvation in the turns from slosh, our turbo was seeing little or no oil for some time. You can see the heat discoloration on the shaft. It seized in the housing and the turbine wheel sheared clean off.

We'll be investing in a turbo oil feed filter. Bigger the better to reduce any oil pressure losses and have room to trap things like the plastic shred.



We need a new turbo. The CHRA saw some hellish wear and doesn't look fit to rebuild. Considering upgrading to a Garrett GT3076R (aka GT30R). It's available with a 0.61 A/R T4 turbine similar to what we were running. It's a dual ball bearing CHRA, so will spool faster than the journal bearing PTE. Also water cooled.

The map looks nice for an M20 at 10 psi boost. If the VE happens to be higher due to boost, we're still in the right ballpark. CFMs look right.

[dvallis]

Here's the start of our race oil pan. E28 528e had an M20 block with this steel pan. We're going to cut off the sump, trim the back to clear our rack and fab a new high capacity sump with trap door baffles. Why steel? We're not skilled a welding aluminum. :-)

[ForcedFirebird]

The Canton Rascing LSx front sump swap pan is a great design to imitate. We used one in the w210 ls1 swap - want to say it was Nissan 240 fitment (front sump) It has a diamond shaped hole in a baffle with four trap doors and a wide girth that is similar to what the m20 needs in an e30.

https://www.youtube.com/watch?v=TF_W1yt2ZEU

[dvallis]

We started with good compression on #1



But not so great on #4 and #5. Engine pull and teardown underway.



Most but not all of the 528e pan holes line up with the M20 block. On to plan B ... cast oil pan butchery. I'll be giving away the pan on for-sale, since it was donated to me.

[dvallis]

Getting ready for engine pull.



Bitch tube mod in progress for improved crankcase breather. Will have AN16 fitting welded on end.

[moatilliatta]

I talked to the MRT guy on eBay, His kit fits stock struts with the Z3 rack. Also found this thread that shows the MRT kit installed. It puts the knuckle really close to the Stoptech rotors he's using. My rotors are also way thicker than stock.(11.75" x 1.25" Hawk DTC) Not feeling grinding the knuckle for clearance. Any comments?

A lot of the bigger BBK need the casting on the outer ball joint of the control arms ground down.


A good rule of thumb is 10PSI per 1K RPM, Some spec E30 guys run the bigger sump pan, Maybe a paul poore makes it. I assume there will still be oiling problem. Vac oil pan baffle has trap doors which help.


If you're using head studs they usually need another torque after a few heat cycles especial with MLS gaskets.


Id pull vacuum on the valve cover into a venturi into the exhaust with a catch can in the middle of the routing. As long as your running no cat, high flow mufflers, it should pull a vacuum.

Stim tech I think made a billet valve cover with dual vac ports, It looks strong, wont crack that one! Id even consider to be a head girdle...


Vband clamps can be so annoying. Especially when they use a stainless nut on stainless stud. They seize instantly!! If you're lucky enough and they are metric you can put a washer and OEM copper nut on them.

[McGyver]

Bitch tube mod in progress for improved crankcase breather. Will have AN16 fitting welded on end.

Dumb question:

On my stock m20 running factory management, when I pull the oil filler cap at idle the engine stumbles. Is this because engine vacuum is sucking unmetered air into the intake through the vent tube? (meaning the stock ECU with an AFM can't handle a vent-to-atmosphere catch-can, and would require the catch-can to be plumbed back into the manifold)

Once I switch to MegaSquirt and a MAP sensor, the vent-to-atmosphere may suck in air at idle but will vent crankcase pressure under load. Both are OK because the MAP sensor is just reading the manifold pressure.

Is that how it works?

[dvallis]

It's a vacuum and afr thing. The stock throttle body has inlets between it an the MAF, one of which goes to the valve cover. Open the oil cap and you change the volume of air from head to intake manifold through a hose. Idle Air controller is supposed to compensate. You might have a defective IAC valve, wiring or hose.

[Northern]

Most but not all of the 528e pan holes line up with the M20 block. On to plan B ... cast oil pan butchery. I'll be giving away the pan on for-sale, since it was donated to me.

If it's just the holes, is there some reason you can't just plug/redrill?

[moatilliatta]

I wonder if the pan is squished or something, shows using the same gasket as all M20's Minus an iX.

http://bmwfans.info/parts-catalog/11131730234/

[dvallis]

We could drill it, plug and grind holes but that sound like a PITA. Going with the modified cast pan for now. Long term I'm going to scan a pan flange, recreate in CAD and do a custom pan

[dvallis]

New bitch tube with AN16 vent.. It's gonna breathe much better.

[dvallis]

GT3076R aka GT30R ball bearing water cooled turbo rated for 525 HP on re-flanged downpipe.

Compressor: 4" inlet, 2" outlet, 0.64 A/R, 57 mm inducer, 76 mm exducer, trim 56
Turbine: T4 undivided inlet, 3" V-Band outlet, 0.63 A/R, 60 mm inducer, 57 mm exducer, trim 84

With the new 10:1 compression ratio and this fast spool turbo it should be quite a ride.

[dvallis]

A few more rebuild pictures

[dvallis]

The mystery continues. No cracked rings on 4 or 5. Rings installed the right side up. Rings clocked correctly. No piston damage. Moving on to valves.