View Full Version : M20 turbo/ or m50 swap

06-24-2004, 10:46 PM
hello bimmer heads! my stock m20 motor has about 250k miles on it and im planning to rebuild the whole motor again with a T3 turbo along the side, but should i instead just replace the whole $h!t with an M50 (including the tranny the ecu ..) and is it worth it. IF so, please tell me more and hit me up with a link to where i can get my hands on the m50 or m52. thanx

06-24-2004, 11:10 PM
depends, in that case maybe is better just put the M50, but with the turbo in you fresh m20 will be faster than that swapp for sure, and will be more unique and cool, I mean fun to rive

06-24-2004, 11:56 PM
hey! nice set up, hmm i like the ideal of turbo charging my fresh M20. I have the t3, but where did u get your intercooler, bov, exhaust flange...ect? to make this happen. and how much gain did you get out of it?

06-25-2004, 01:38 AM
If you are asking these sorts of questions, its very obvious ( to me anyways) that doing a turbo on your m20 is not something you need or should be doing.

06-25-2004, 04:10 AM
We all have to learn somewhere.

On a stock motor you can expect 10hp for every 1psi of boost. A 12psi setup is pretty easy and will get you around 300hp at the crank.

The exhaust flange many use is an adapter manifold that connects to your stock dual manifolds. You can have one fabricated or buy it from www.proturbo.fi

Try to stay away from a FMU or fuel pressure raiser. They are just a headache and not optimal in any way. For not much more you can get a MegaSquirt ($260 assembled) stand alone system and some large injectors.

You can find intercoolers at junk yards or on ebay. Read the turbo faq at the megasquirt site (www.megasquirt.com) for information on large factory type intercoolers you can get cheap.

I would recommend a hybrid t3/t4 in your application, but a t3 can work for less boost. My BOV is a turbo xs RFL, but don't worry about that so much. Just start collecting parts.

If you are going to do a re-build get the turbo diesle crank and build a lower compression 2.7l stroker motor, perfect for a turbo. You can do this with stock parts from other e30s.

There are many avenues for upgrades on a turbo setup once you get it running. My goal is 400 or more crank horsepower.


Bimmer Heaven
06-25-2004, 11:16 AM
The M50 swap will be a lot more reliable then the turbo, it will be easyer to do and might end up cheaper. It depends what you want from your car!

06-25-2004, 04:29 PM
Well, already Dan gave you some pretty good info, except that the FMU is not a headache Dan, I have one and neger got a problem with it, it's a cheap solution to run stock ECU since you won't put larger injectors than 21-24 LB/h size, if not the ecu won't handle and will cosume gas like hell.

The FMU helps to fill the cilynder to compensate the air of corse while will be doing the Job of a big set of injectors.

The turbo adapter is custom, I just printed out a paper from the Proturbo manifold and copied it in my cr, we builded that manifold almost in the car.

The Intercooler you can search in Ebay, Actually I bought one from StreetImports (ebay) for $200 Brand new, polished and good finish, very good IC.

The BOV is a Apexi, you can always check in Ebay for cheaper stuff.

take a look at my page , there is the BOV

My 325is Turbo (http://members.cardomain.com/m20325is)

06-25-2004, 05:52 PM
great, my engine is being rebuilt at the moment and im collecting the parts that i need for the turbo set up. and thanx for the ideas on what brands i should use (flange, bov ect...) o and ebay sounds cheap so ima look for an intercooler there.

06-25-2004, 06:58 PM
Originally posted by AR13LLE 9
great, my engine is being rebuilt at the moment and im collecting the parts that i need for the turbo set up. and thanx for the ideas on what brands i should use (flange, bov ect...) o and ebay sounds cheap so ima look for an intercooler there.

Sure, I can help you in anything realted to turbo just ask,

about the IC I bought this one, it's compact, fits under my M Tech II front spoiler and it's very nice.



The site http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=33742&item=7907121966

Also check for other size and TYPEs of ICs, cheack carefully there a model that is a bit larger than this one but is different shape and model, I like this one more since has a kind of serpentine inside the runners as well.

Not like this one


check here more pics


I suggest you join e30Tech (http://www.e30tech.com) for better reference, I eman we are like 8 members with mostly custom Turbo kits a lots of stuff to talk about it and great info, we can help you ther more, there is a Turbocharged Section too.

My nickname is diegom6 too.

Let me know how it goes!*th-up*

06-28-2004, 01:37 PM

I pm you.

06-28-2004, 01:39 PM
check PM !

06-30-2004, 08:21 PM
check ur pm ar13lle

07-04-2004, 02:47 PM
considering u have to rebuild ur m20 it would be cheaper to do the swap. in ur case i would do the swap.