M42 Turbo - Scandinavian style

[23732]

definately, the m42 is a way better engine than the m40.

how did the m40 of your brother died?

It blew the headgasjet out because of one of the o-rings did not shut properly. It happened in a pretty steep hill where he was driving past his buddy on full boost ;)

[varg]

Do you have the exhaust manifold set up yet? Any pics?

[ccsdo5]

Maybe I am wrong about the intake but just from others builds and experience I'm pretty positive the intake can't flow that much air. Sure you can cram as much boost into as you want but it won't flow freely like you want. The biggest limitation for sure is the M42 throttle body. It has a dual throttle plate that's also very restrictive. IIRC there was someone who made a M42 to M50 throttle body adapter.

Also a word of caution make sure you check your bearing clearances and crank before putting the M50 crank bearings in. My crank was worn out when I rebuilt my M42 and I developed some bad crank walk not too long after getting it running.

I'll definitely keep my eye out on this, I'm curious to see what sorta numbers you end up with this setup. I would be thrilled to hit 200-250 whp on the stock M42 I have now and wouldn't be disappointed in 300-350 whp on a built M42.

[fresh_TD]

Maybe I am wrong about the intake but just from others builds and experience I'm pretty positive the intake can't flow that much air. Sure you can cram as much boost into as you want but it won't flow freely like you want. The biggest limitation for sure is the M42 throttle body. It has a dual throttle plate that's also very restrictive. IIRC there was someone who made a M42 to M50 throttle body adapter.

Also a word of caution make sure you check your bearing clearances and crank before putting the M50 crank bearings in. My crank was worn out when I rebuilt my M42 and I developed some bad crank walk not too long after getting it running.

I'll definitely keep my eye out on this, I'm curious to see what sorta numbers you end up with this setup. I would be thrilled to hit 200-250 whp on the stock M42 I have now and wouldn't be disappointed in 300-350 whp on a built M42.

200whp on a stock M42 is not difficult to achieve...the turbo kit sold by jake at classic daily achieves that at 9psi.

Sent from my Samsung Note 4

[CorvallisBMW]

sub'd for turbo fun

[ccsdo5]

200whp on a stock M42 is not difficult to achieve...the turbo kit sold by jake at classic daily achieves that at 9psi.

Sent from my Samsung Note 4

I'm aware of that, but I will be abusing the car and it'll live most of its life up at the limiter on track... I also have probably like 150,000+ miles on it (I'm not exactly sure) it has never gotten a head gasket, the timing chain is pretty loud, and I don't plan to do anything to the engine until it sorta goes bye bye. I also have a slightly larger turbo than what Jake uses on his kit I believe. I have no doubt the car would be above 220 whp on a bar of boost I'm just a little scared the head gasket won't hold. that's why I said "on the stock m42 I have now" lol

[elcoy]

Man I cant wait to see where this goes... Looks like there is a potential for a wealth of information in turbo M42 building! Sub'd

[23732]

Do you have the exhaust manifold set up yet? Any pics?

Not yet, as I need twin-scroll, my brother has to custom weld one for me.

Maybe I am wrong about the intake but just from others builds and experience I'm pretty positive the intake can't flow that much air. Sure you can cram as much boost into as you want but it won't flow freely like you want. The biggest limitation for sure is the M42 throttle body. It has a dual throttle plate that's also very restrictive. IIRC there was someone who made a M42 to M50 throttle body adapter.

Also a word of caution make sure you check your bearing clearances and crank before putting the M50 crank bearings in. My crank was worn out when I rebuilt my M42 and I developed some bad crank walk not too long after getting it running.

I'll definitely keep my eye out on this, I'm curious to see what sorta numbers you end up with this setup. I would be thrilled to hit 200-250 whp on the stock M42 I have now and wouldn't be disappointed in 300-350 whp on a built M42.

I will check the clearances with Plastgauge. Might have to buy myself a Bently manual to have controll over the tourques and clearances.

We'll see what the poweroutput is, there is always an oppertunity to exchange it later and get it tuned accordingly. But I didn't know the E30 intake had a dual throttlebody? If so, I might change it out to a single, large one.

Also, M54B30 pistons looks like the best choice for low-compression builds.

[word is bond]

A 400+ hp M42 Touring!? Sub'd. You Scandinavians are wild. Looking forward to seeing where this goes.

[23732]

A 400+ hp M42 Touring!? Sub'd. You Scandinavians are wild. Looking forward to seeing where this goes.

Making the touring as stealth as I can, while have bucket seats and a cage in it. I am also trying to get the car as close to a tonne as possible ;)

[elcoy]

Holy eff I totally didn't realize it was going in a touring! I already thought it was cool now it's ice cold.

[23732]

Here is a better picture of the car. It has been straightned and only needs a new b-pillar and outer sill (which are bought). New doors are already bought and painted the same color.

[econti]

maybe it gets a little faster revving, but less eating out the crank? i don´t know for sure.
But no worries, like OP says: it doesn´t have to last long, and MM probably uses them for a reason indeed.

The new bearing sets have 360 degree thrust surfaces, unlike factory bearings

[varg]

The new bearing sets have 360 degree thrust surfaces, unlike factory bearings

Critical :up:

Fixes one of BMW's biggest screwups with the M42.

[wazzu70]

I have an M42 running on VEMS. I can send you the primary trigger settings when you get to that point.