Wait, what are you waiting for? I see 2 hours of welding and fitting and you've got a turbo Porsche. I seriously thought you might be bench racing but by the looks of thing you're just waiting for a triple-dog-dare...
Wait, what are you waiting for? I see 2 hours of welding and fitting and you've got a turbo Porsche. I seriously thought you might be bench racing but by the looks of thing you're just waiting for a triple-dog-dare...
He he he he.
And I have not even posted the photos of the M62 Yet. I have already designed the mounting bracket and sourced all the parts for that as well.
It is getting forced induction. I am on the fence about exactly what kind.
At the moment I am really liking the rear mounted turbo. I have to figure out the oiling and the water cooling and if I need both. The turbo is designed for them. I was thinking of complete rear mounted setups.
Oiling: I want to only run one pump. So can I just mount a tank in one of the rear fenders and plumb a pump to move the oil to the turbo? Can I put a pump after the turbo and suck the oil through the turbo? then force it through a small cooler (I was thinking a trans cooler mounted up behind the gas tank near the dif) and then plumb that back to the tank in the fender that would hold say 1-2 quarts? I like having the oiling separate from the motor. This means I can run an oil that is optimised for the turbo. It will also keep the system cleaner (I hope) If I really wanted to get creative I would put a remote mounted filter in the system as well (again housed in the rear fender)
Cooling: I am not sure about this one. Part of me was actually thinking of running oil instead of coolant. This would make plumbing really easy. One pump pulling oil through through both sides of the turbo housing. There may be a bit of a balancing issue. I could just use two pumps (I am thinking Bosch fuel pumps for the oil since I would run a much thinner synthetic oil)
However since the turbo is designed for coolant and not oil I am sure there would be some type of issue that I am not thinking of. SO I could put a small tank and a pump in the other fender and circulate it through a small cooler tucked up in front of the gas tank by the dif. (next to the oil cooler)
I don't now what I am going to do. I really like using a stand alone oil based system to both cool and lubricate the turbo. With the turbo being so far back from the motor it will not see nearly the amount of heat that a manifold mounted unit does. This makes me think that it may be possible to go this rout and most of all it keeps the system very simple.
What do the experts say about my hair brained idea?
I always thought rear mounted turbos were interesting. I'm going to follow your progress closely! More pictures! 
Another weird question. If I suck the oil through the turbo from a tank mounted above the turbo does indexing the center section become moot or do I still need to have the oil inlet on the top? I was actually thinking that I may want the inlet on the bottom and then the pump would pull the oil up through the turbo.
I wonder if I put the pump so it was forcing oil to the turbo if the pressure would force it back around to the tank. That way i could pull the oil from the tank through a cooler and force it in to the turbo
Ok I just done know what to do with this one as I don't want to run two pumps for oiling and I really don't want to plumb it into the motor. I want a stand alone oiling system for the turbo in the rear.
If I sucked oil through the turbo (both oiling and cooling) I could then put a turbo timer on the pump and keep the turbo happy. Probably not needed but.. . .
So the root of the matter is to pull or to push the oil?
dean1484 wrote: I would imaging that the exhaust side needs to be a bit smaller to spool up faster due to the cooler exhaust temps.
In the turbocharger section on Yellowbullet they do mention sizing down the hotside pipe for rear mount.
I am kicking around the idea of building one.....I saw Mike Murillo's rear mount car run one time. It was a beast, with a trunk-full of go go.
Taiden wrote: I always thought rear mounted turbos were interesting. I'm going to follow your progress closely! More pictures!
Will do BUT I am also finishing up the MS wiring as well. I have it on the bench with a gutted DME and a complete wiring harness at the moment testing all the sensors through the harness and getting the wiring strait before I install it on the car. I have to make several patch cables that run from the harness to several of the sensors as I am using some non oe ones and I am also changing from a 944 TPS to a 951 TPS so I can have flood clearing capability as well as letting me use preset values on the TPS scale to control other things like when the boot comes in and fans and things.
Anyway we will see. I have been working on this for 2+ years so I hope to have it complete by this summer.
In reply to dean1484:
Speaking from experience, get MS working running the car and figure out the basics of tuning your map, I know it doubles the tuning work once you go FI, but at least you're starting from a baseline. We spent a lot of time just getting the XR4 running at first, and our part-throttle off-idle tuning took a lot longer because we were learning to tune with boost right out of the gate. Matt from DIYAutoTune might have some better words of wisdom. I've heard the new auto-tuning software actually works (it didn't years ago when we installed ours). Might speed up the process...
There are a bunch of rear-mount build threads with oil scavenge pumps (SHURflo 8000 series oil pump comes to mind), I remember several threads over on thirdgen.org...
In reply to Raze:
I gotta disagree. I started NA thinking it would be easier and installed the turbo later. I wish wouldn't have. You throw away the spark and fuel maps that you spent so much time working on. You pretty much start from scratch all over again.
To the OP I recommend deciding what boost level you want to run and base your maps a fair bit higher, because you WILL turn up the boost later. Are you street tuning with a wideband or going to the dyno? On the street set the boost controller down and work up, on the dyno just go all out the first time.
The seals in the turbo may be designed for pressure retention of the oil flow and if you are vacuming the oil out of the the housing it might suck air past the seals...Probably have to test it. As the seals wear, bad seals would show up as bubbling in the fluid not leaks from the housing, this could mask pending bearing failure due to poor oil flow.
dean1484 wrote: It is getting forced induction. I am on the fence about exactly what kind.
Th obvious answer is both. 
ditchdigger wrote: In reply to Raze: I gotta disagree. I started NA thinking it would be easier and installed the turbo later. I wish wouldn't have. You throw away the spark and fuel maps that you spent so much time working on. You pretty much start from scratch all over again.
Yeah but isn't just doing it once for the experience worth it? Would you really want to have tuned the turbo setup with zero previous experience?
In reply to Taiden:
By that time it was my 4th MS install.
I really don't see any added degree of difficulty with boost. Higher risks to be sure but it isn't any easier without it. Boost was a lot more rewarding though
ditchdigger wrote: In reply to Taiden: By that time it was my 4th MS install. I really don't see any added degree of difficulty with boost. Higher risks to be sure but it isn't any easier without it. Boost was a lot more rewarding though
I should have qualified my statement, we got it running with stock injectors 35#ers with the Holset on there first time (with boost locked down to 10 psi) with an open downpipe exhaust, and had to redo everything when we went to 75#ers and 30psi a cat, muffler, and full 3" exhaust, but the initial setup, though a waste, gave us practice and experience with tuning, particularly regarding initial startup and off idle, pre-boost. I would only bring up doing it in stages so you don't blow a HG or anything going straight for the cheese which is so easy to do once you have MS working and the first few times you feel your turbo really spool up 
I don't know what's so hard to understand about it and it's certainly the case.
Admittedly i dont know jack E36 M3 about thermodynamics but i was pretty sure kinetic energy was based on mass and speed. Im right with you on the mass not changing through the turbine. Feel free to explain how the speed doesnt change.
As for me picking up a textbook... lolno. I already know how to slap together turbo E36 M3 that works and generates giggles. I also refuse to do math for a living. Considering those two basic facts, the cost/benefit doesnt add up. But i WILL read your entire reply.
Generally, there is negligible kinetic energy loss in the whole system, but since the exhaust section uses both an impulse AND reaction style turbine, there is a kinetic energy loss in the gas flow across the turbine. This lost kinetic energy is translated into rotational kinetic energy of the rotating assembly, with a minuscule amount converted into heat through drag from the bearings. With more modern turbine designs, this loss is reduced, but I'm not certain if it's been eliminated alltogether
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