M42 Turbo

[318isteve 0]

Hi there,

Not by any means building this now but i own a 318 and want to put a m42 into it with abit more go, forced induction seems to be thhe way to go. im after about 250-300 horsepower..

has anyone done this?

And any reccomendations on setup? having a search on good ol' google and megasquirt, t3/4/5 turbo bigger injectors, metal gasket fuel pump etc should get me there but im still abit lost.

im only a student so a dont have an open budget and have looked down the 2.5 swap but if i did this i would have to replace my suspension, struts and brakes etc so cost will end up being similar anyway so why not go for something less common.

lots and lots of questions, any help would be appreciated guys cheers!

[Mark 178]

have looked down the 2.5 swap but if i did this i would have to replace my suspension, struts and brakes etc so cost will end up being similar anyway so why not go for something less common.

lots and lots of questions, any help would be appreciated guys cheers!

You'd still have to replace the brakes/suspension etc .... 250-300 horsepower is the same no matter which engine it comes from!

[CamB 48]

Does no one ever search? Andrew had one.

Actually that's a bit harsh - the problem is that the search engine on the site ignores three letter searches, which is extremely friggin annoying when BMW uses 3 digit engine codes...

http://www.bimmersport.co.nz/forums/index....43&hl=turbo

http://www.bimmersport.co.nz/forums/index....07&hl=turbo

http://www.bimmersport.co.nz/forums/index....94&hl=turbo

Will cost heaps. All turbo conversions cost what you think they will cost, multiplied by 2. It's strange - even you try and do it cheap, it will cost cheap x2. If you try to do it right, it will still cost 2x the higher number...

[Jeddy 0]

250-300 will need forged internals and standalone=big dollars

Just get a m50/m52 first

[320guy 0]

250-300 will need forged internals and standalone=big dollars

Just get a m50/m52 first

No, just no.

My mate has a turbo m42, got it dynoed last month. 300whp.

Engine hasnt been opened, or messed with apart from a new head gasket. Yeah, you will need a stand alone to do it properly.

[Jeddy 0]

Andrew/Gus's turbo m42 is about 300hp right? Thats running like 2?something pounds of boost. No way could a stock engine safely and consistently run that. How many pounds is the one you know of running?

Also pic's of your mates turbo. Love to see another one floating around.

Edited November 26, 2008 by jeddy

[320guy 0]

I think its running around 16~psi -

Was dynoed at 300whp, and he rapes the crap out of it and had no problems (has been turbo for a couple of years now)

Edited November 26, 2008 by 320guy

[Gus 5]

that's an e36 M42 engine - would be interested in finding out a bit more - it does seem some pretty high numbers on stock pistons???

can't really recommend it on a cost/benefit ratio..good fun though!

[318isteve 0]

Cheers CamB for the links, heaps of great info. and yea it is a pain.

300rwhp would be amazing on a stock m42

i may be looking at a 1 that has a blown head gasket from the local wreckers and re-honing that etc.

does anyone know of a company who makes reasonably cheap forged pistons? or pistons from another motor that will fit once i rebore?

also is it worth looking at stroking the engine with the turbo or would this make it weaker/not worth it?

[Jeddy 0]

There are alot of Piston companies, Ross, JE etc but there not going to be cheap. What were you planning on stroking it with? M47 crank? to take it out to 2.1 with an overbore?

[E30-323ti 66]

Cheers CamB for the links, heaps of great info. and yea it is a pain.

300rwhp would be amazing on a stock m42

i may be looking at a 1 that has a blown head gasket from the local wreckers and re-honing that etc.

does anyone know of a company who makes reasonably cheap forged pistons? or pistons from another motor that will fit once i rebore?

also is it worth looking at stroking the engine with the turbo or would this make it weaker/not worth it?

IIRC you can use a M47 crank (diesel motor) + re-bore and you are around 2.1l, not sure what rods (S50B32 rings a bell, but that might be the pistons??), but you would prob. want some H-beams to go with the forged pistons if you are going turbo and then balance the whole thing up.

[CamB 48]

A quick look at the Wiseco catalogue suggests there may be a Mitsubishi option if you can find rods to work with it.

But its unchartered territory though...

[Jeddy 0]

IIRC you can use a M47 crank (diesel motor) + re-bore and you are around 2.1l, not sure what rods (S50B32 rings a bell, but that might be the pistons??), but you would prob. want some H-beams to go with the forged pistons if you are going turbo and then balance the whole thing up.

Yea thats the combo. Althought i'm not sure how easy it'll be finding a m47 crank and s50 pistons in NZ for cheap.

[tire 10]

M44 or m47 crank, info: http://www.e30zone.net/e30zonewiki/index.p...42_Stroker_Info

[320guy 0]

that's an e36 M42 engine - would be interested in finding out a bit more - it does seem some pretty high numbers on stock pistons???

can't really recommend it on a cost/benefit ratio..good fun though!

Yeah its from a e36, was orignally a 316. Not sure what the differences are between the e36 and e30 m42... Just a different intake manifold?

He has had no problems with the standard pistons, as long as your tune is good they should be fine.

Running a microtech ECU. Not exactly sure what model turbo, I think its either a Garret GT30 or GT35, though I think its more likely to be a GT30...

Water injection (though only uses it when he gets a bad batch of fuel)

Huge ass wilwood brakes.

Bilstein suspension.

Edited November 27, 2008 by 320guy

[318isteve 0]

hmm so perhaps a m44/m47 crank with a slight over-bore with s50/mitsi pistons would get me around 2 litre, if all else fails i could keep the m42 crank as (correct me if im wrong) they are forged.

if i could put a copper gasket on there and lower the compression alittle then i should be able to run 10-12psi safely?

one more this may sound stupid but could i fit roller rockers from a m44 onto the m42?

[Jeddy 0]

The cost for the extra .2l is probably not worth it. Just turbo the 42 as it is

[318isteve 0]

oh ok i wont bother about stroking then,

still leaves me with new pistons does anyone know more about the misti pistons?

would solid lifters from a s50 be a worthy thing to look into for increasing redline or again dont bother?!

thanks again

[320guy 0]

oh ok i wont bother about stroking then,

still leaves me with new pistons does anyone know more about the misti pistons?

would solid lifters from a s50 be a worthy thing to look into for increasing redline or again dont bother?!

thanks again

If you are only looking for 250 - 300hp, dont bother messing around with the internals. Just get a decent aftermarket ecu and a decent turbo then get a solid tune for it and you should be good to go

[318isteve 0]

sweet

like i said the sheap engine ive found has a blown gasket (needs to be replaced anyway) so a re bore would be good is +.25 the next size to bore to?

and what sought of CR ratio is your mate running? is he in hamilton?

[320guy 0]

sweet

like i said the sheap engine ive found has a blown gasket (needs to be replaced anyway) so a re bore would be good is +.25 the next size to bore to?

and what sought of CR ratio is your mate running? is he in hamilton?

He is in auckland, he is running standard compression ratio. Nothing has been changed.

Also, stripping the engine down and boring it out and putting new pistons is as alot bigger job (and alot more expensive) than just replacing the gasket...

Edited November 27, 2008 by 320guy

[Jeddy 0]

sweet

like i said the sheap engine ive found has a blown gasket (needs to be replaced anyway) so a re bore would be good is +.25 the next size to bore to?

and what sought of CR ratio is your mate running? is he in hamilton?

If you want to spend some money get it honed and get custon pistons then you can choose your CR and allow for potentially more boost.

[318isteve 0]

alright so a hone and new pistons, metal gasket, megasquirt and some new injectors and turbo set up?!

does anyone know about the Karl Schmidt pistons on trademe or know of using mitsi evo pistons?

does $450 sound like a reasonable price to pay for the bare motor?

[320guy 0]

$450 isnt too bad.

You will probally find it will be cheaper just to get a Link ECU rather then a megasquirt. Also more support in NZ for link (tuners, installers etc).

[antony 0]

Cheaper to get a Link than Megasquirt???

I don't know about m42's, but with m20's Megasquirt is over $2000 cheaper