Turboed M30 E30

[KrayZE30]

Ive been thinking of buying a low milage 5,6, or 7 series and swaping its M30 engine into my car along with hooking up a turbo to that beast. The cost would probably be somewhere around 2k for the car and 2-4k for the turbo I think.... Although, I'm concerned how badly this engine will affect the balance and handling of my car.

I could also go in the direction of rebuilding my 170k mile shitty compression m20 and turboing that or even swapping in M50b28 engine with M3 cams. Although, I dont think you get very good performance out of the M50 for the amount of money you have to invest. Especially If you want to turbo that thing.... damn....

Overall, I think that I could get the most bang for my buck by swapping in a turboed M30.

M30 + Turbo = 285-350hp
M20 + Turbo = 240-275hp
M50 + M3 Cams = 220-230hp
(These are all just very rough estimates. Correct me if I'm wrong)

What are your thoughts on this? I wanna hear it all. Good, bad idea? Go with the M50?

[LowR3V'in]

A guy on bimmerforums turbo'd his M50 and ran a best of 12.8@112 w/ 313rwhp
Don't know the boost, but mentioned that he ran 5psi just fine with his 10:1cr
and when he bumped it up to 8 it "created ring problems".


Here's was "TCD 535i" had to say; He is affiliated with http://www.turbochargingdynamics.com/ or might even be the owner. :?:

Q:I get the feeling that boasting the highest HP stock bottom end is like bragging that you have the most compromised and potentially unreliable setup.

A:Yep, that was a stupid comment. I think it is highly unlikely that the bottom end of the m20 is the weakness of the motor. This isn't a m50/s50/m52/s52 motor with high compression and lightened rods that doesn't like boost.

The m20 has only 8.8:1 compression and is extremely stout. It's weakness is the headgasket as with most n/a motors turned turbo. I suspect that studs extend the life of the headgasket to a reasonable length of time.

I would say the E30 motor is the most reliable and cost effictient.<--- did I spell that right?

[iXer]

I would keep the M20, blueprint it and then turbo it. I'm no expert but I know a lot of knowledgeable guys and have read up on the M20 in particular as it sits in my 325iX, though I no longer have turbo planned for it.

Build/get a proper exhaust manifold (pulse split for good street performance), a big intercooler (can never be too large), a turbo made for the kind of power you need (Holset HX40 = low exhaust manifold back pressure), and all the usual forced induction trinkets (wastegate, dump, ..) - then all it takes is to control fuel and ignition.

Basically I would invest a lot into reading up on engine management, replacing the stock ECU with an aftermarket one controlling both ignition and fuel. MegaSquirt comes to mind, I've got one going into my Volvo.

As LowR3V'in quoted: the headgasket is the weak spot on this engine. O-ringing the block to keep the headgasket in place with a steel wire is a good remedy but doesn't help remove the cause of the problem. The M20 combustion chamber is shaped in a way which is prone for detonation more easily than a more modern engine like the M50. Using after market pistons helps, as well as changing the shape of the combustion chamber in the head. This is where the knowledge of turbo engine experts is needed to reach the really high power on this engine.

300 hp is no problem out of the engine, if you have programmed your ECU correctly given the conditions I mentioned.

Feel free to question what I've said just here, I'm no expert.

[grk325]

M20 + Turbo = 240-275hp


buddy a well built turbo m20 can sure produce way more power than that ;)

i dotn see why it cant produce more than 400hp..and yes it costs :roll:

[Erick]

Re: Turboed M30 E30

M30 + Turbo = 285-350hp

Patrick, e34biturbo on bimmerforums, got his M30 powered e30 M3 to 610rwhp. Not bad eh? :)

But in the end it's all about how much you pay to play.

[KrayZE30]

Yea, after doing some more reading, I'm starting to lean toward turboing my current M20 engine. I'm looking to spend around 3000-4000 on a turbo setup. Hopefully I can push some good numbers. Anything above 240 rwhp would put a smile on my face. Well, I wont have the money till most likely the end of summer, so I still have a long while to research this topic.

But still, my main question is how come not too many people put turboed M30's in their e30? Are they a worse canidate then the m20 for FI?

[LowR3V'in]

Because not allot of people are hardcore like that. :o

[Bmwbro]

turboing the IX

if i were to turbo my 88' m20 325ix, would the transfer cases be able to handle the power? what about an engine swap? not to steal the thread, but just wondering.

[Erick]

Re: turboing the IX

if i were to turbo my 88' m20 325ix, would the transfer cases be able to handle the power? what about an engine swap? not to steal the thread, but just wondering.

if you do an engine swap you are changing the whole damn drivetrain with it, making it a rear wheel drive. Then yeah you can turbo it.

As for the turbo m20iX, I think that wont last long because I hear transfer cases are already a bitch on STOCK 325iXs. I can't imagine what a forced induction iX would cost it's owner in transfer cases. :roll:

[decay]

i'd swear i'd heard of at least one guy with an m50 325ix... he just used the oil pan from his old m20.

i could be wrong.

i'd kill any of your mothers for an awd turbo e30, myself.

[Jordan]

i could be wrong.

[Bmwbro]

i'd kill any of your mothers for an awd turbo e30, myself.

exactly. it would be unreal. it must have been done by somebody before.

[decay]

alright, so what other than the oilpan would prevent an ix owner from dropping in an m50?

[Rob]

Re: Turboed M30 E30

most bang for my buck

turbo the m20, its already in the car, which will cut down on a lot of costs, and then you can do a better turbo setup as opposed to spending more money on a motor swap and skimping on the turbo setup

[Erick]

alright, so what other than the oilpan would prevent an ix owner from dropping in an m50?

The drivetrain.