Quick spooling budget rear mounted turbo M50tu?

[THEhomelessONE]

Well I finished the m50tu swap not too long ago and I need more power. Would like to have full boost by 3k and around 300whp using a holset or other cheap turbo.

I would rather have a rear mounted turbo since I'm in CA, no manifold or major exhaust work needed, ease of install. I'm hoping I could use an hx35 but it may have too much lag, hx30 maybe?

The main thing I'm worried about is tuning, is there someone that could flash a safe tune on a stock chip without a dyno? I have a 413 ecu if it matters.

Just need something that'll keep me happy until I can swap in a v8, threw in the m50tu since the m42 went out two weeks after I bought the car, wasn't planning on doing a swap anytime soon $$$

I appreciate any advice that can help towards the project (scavenge pumps, fittings, piping diameter, etc.) Will post pics of the vert when I get her back from paint, TIA!

[TheTacoMan]

Having researched Rear mounted turbos in Truck applications, I can tell you it will still cost as much as a normal manifold mounted turbo setup.

[Exodus_2pt0]

With all of the available cheapo manifolds and available hood space, there is no reason to go rear mount.

[THEhomelessONE]

What brings the cost back up? I would love to keep it under 1k, but 1.5k max. I'd like to be able to reverse everything in a couple hours and throw her in for smog when needed, plus the stock manifold was a pain to work around, want to avoid it if possible.

[TheTacoMan]

Oil pump, oil lines, all the extra piping and all the supporting turbo mods. 1.5k might get you a turbo setup but it wont be ideal.
Tuning is very important, which usually isnt cheap.

[THEhomelessONE]

Yeah didn't think an oil pump would cost so much, I still want to go with a rear mount though. Any advice on what I can do for tuning on a budget? Thanks!

[ak-]

Being you live in CA, just do a bottom mount setup.
My friend's e36 turbo has had his hood opened 3 times after getting pulled over and they never even noticed. Even car guys at meets didn't notice it was turbo charged. It literally looked like a long cold air intake or something.
Just don't go getting fancy colors and shit or mount your BOV near the throttle body like everybody does.

[THEhomelessONE]

I'll keep that in mind, but really want to be able to go back to stock within a couple hours if needed. I don't want to put too much effort into this. Any advice on what size holsets to look for or tuning? I understand it's more efficient to just do a regular turbo install, but honestly if I can't so a remote mount I'd rather keep it NA and suffer until I can afford an LS swap.

[Exodus_2pt0]

If you are serious, I'd wait to do the ls swap.

That said, I built a 5.0 e30 and missed the straight 6. I would rather have a turbo I6 than the v8.

[mitchlevy7]

I'll keep that in mind, but really want to be able to go back to stock within a couple hours if needed. I don't want to put too much effort into this. Any advice on what size holsets to look for or tuning? I understand it's more efficient to just do a regular turbo install, but honestly if I can't so a remote mount I'd rather keep it NA and suffer until I can afford an LS swap.

then dont do it....sorry to be a dick

[THEhomelessONE]

The ls swap will take a couple years, why didn't you like the v8? A remote install makes more sense to me than doing a traditional setup. I'm pretty confident I can have everything finished within a week, I just need to plan it all out, don't like being caught off guard.

Only thing I'm really concerned about is the tuning. If I can run on e85 that'd be even better. Any recommendations on turbo choices? Leaning towards the hy35.

Sorry, what I really meant by too much effort was having to take everything on and off again if I get harassed by the popo, as well as the risk of clearance issues and custom exhaust fabrication. A remote system seems pretty straight forward.

[TheTacoMan]

the risk of clearance issues and custom exhaust fabrication. A remote system seems pretty straight forward.

I hate to burst your bubble but there will be extensive fabrication as well as clearance issues with a rear mount, an e30 isnt exactly a big car with alot of room. Rear mount turbos are often used in trucks and other bigger vehicles with large engines that do not have room for a turbo in the engine bay.

You like the idea of a rear mount turbo but havent thought out any of the logistics and how you would design it. Its a waste of time when there is a variety of bolt on manifolds. If you are so worried about the po po then make a big engine cover or something.

[Q5Quint]

I think a rear mount would be way harder than a front mount. You have to custom everything instead of buy an off the shelf manifold and bolt up. Then you have to custom the parts to bolt back on if you remove them every time.

I think it would be better to do a stealth bottom mount since you already have an updated engine. They wont know the new engine is or isn't supposed to have a turbo.... I think. As long as the codes read right and the tailpipe check is legit.... how do they know you don't have a new twin turbo bmw engine in there?

I am not up on the cali laws but you might want to consult someone who is or has a shop there. A rear mounted turbo could actually be worse since it is obviously added and removed to pass inspection, while a stealth oem looking install with a newer engine would fool anyone who doesnt know about bmw engines specifically while they are staring right at it.

[THEhomelessONE]

Lol don't underestimate Cali police, most of them know what engine codes to look for and where to find them. My friend had his supra impounded for adjustable cam gears. I plan on getting BAR'd when I get it back from paint, then boosting.

Honestly, what is there to fabricate? Running piping back up the chassis? I could probably get away without running an intercooler as well if I used aluminum piping. The turbo would be larger than the stock muffler, but not so large it couldn't fit, and doubt it would be lower than the diff.

I'm fairly confident with everything except what to do about tuning, what fuel pump and injectors to use with e85. Would rather run e85 since it's almost like running 116 octane and has great cooling properties. Plus it's $1/gal cheaper and stations keep showing up here in CA.

[kamotors]

What about the 10+ feet of oil lines, the $300 scavenge pump, the fact that its very hard to route large pipes under an E30. Megasquirt ECU is $650 alone. Theirs no way your going to be able to use the stock exhaust setup and have a decent setup.and to run ethanol you need MASSIVE injectors, newer fuel line and once again a proper ECU tune

its will be much more expensive to run the rear mount setup, and if not tuned you will pop the head gasket and have to redo everything.

just do it right the first time if your going to go boosted.