M42 Turbo Build

[Minimayhem81]

Hello, i have just started a M42 turbo build as a little project while im at uni.
I bought a car last monday, its a E36 1995 but with the M42 engine, with the intention of buying the bits and bobs to make it like an E30 one.
After reading a thread just a few mins ago, i read the crank and pistons arnt the same (not forged)? Can someone please confirm this??
As i want to turbo it, this kind of make a diferance!
If i have bought the weaker engine can some surgest a combination of conrods and pistons i can use instead? Iv read about quite a few random combinations but am unsure if i want to try it, what have other people used before and know they work?

Many thanks!

[rix313]

What do you mean by "with the intention of buying the bits and bobs to make it like an E30 one."?

A 1995 engine doesn't have the forged bits, the E30 variants however do, so you'd need the gubbins from an E30 M42. You can build a low comp engine as I was looking to do by fitting an M42 crank to an M44 block, rods and pistons...

Also, whats your budget?

[Minimayhem81]

i meant the intake, sump ect...?
hmm ok thats bad...
need to find some pistons and rods i can use in this engine, maching isnt a problem so iw ould deck the block pocket the pistons whatever needed to be done.
my budget is well i dunno really
The car was £350 going to brake it sell what i dont need, £300 for an ECU you can get some alright second hand ones which would do the job. At work i make engine and chassis harnesses so wireing isnt an issue. Turbo, £100-£150, Manifold was going to make. charge pipeing and intercooler £120 ish (ebay job). hmm what else, well thats the basics for now will get bigger injectors if needed. dumpvalve can get for £30 ish. All the little bits like oil feed etc will come out in the wash have that sort of stuff already.
But the main bonus is i have free access to a dyno as i do motorsport engineering at uni so thats about it budget wise.

Think it will work?


So.... What Pistons and Rods?

[Gunni]

you also need exhaust, clutch

[Minimayhem81]

Yep sorry forgot that £200 for clutch and not going to bother with a nice exhaust yet as it will just be something to play with, simple pipe to extractor for dyno will do. Also forgot all my ARP Bolts! what is it £120 for head bolts £70 for bottom end?
It will all come in time i can start building the engine up when i know what im using

[Minimayhem81]

How strong are M50 conrods? 5mm shorter skim the block get the right CR?

Night all

[rix313]

I've given you a recipe for an easy low comp engine above...

ARP don't make specific kits for the M42 you need to buy kits from the later 6 pot engines and just have spares. I have a list some where of which kits you need.

I would also budget bigger brakes into your costings.

There's a trader on here called Injector tune who can sort you with larger injectors

[Minimayhem81]

ok spose i better try and sell this car. lol any one want a E36 318is comapct? haha

Yeah i know you have to but the bolt kits for the M20, if i remember correctly.

As for injectors ill get it all built and working and dyno'd and if the injectors need improving ill do it then

The brakes ill sort then i put it in an E30 would the suspension from a compact iv got the vented set think they would be big engough? or am i going to have to get the M3 ones? well it dosent matter yet as its only the engine im doing, the car wont be road or track legal for a long while...

[rix313]

Yeah i know you have to but the bolt kits for the M20, if i remember correctly.

You remember wrongly lol. I put this together a while back

ARP P/N: 201-6303 for the BMW 2.8L M52 con-rods can be used on the M42 rods (they use the same M9 x 47mm bolt).
ARP P/N: 201-5000 for BMW M50, M52 main bearing studs can be used on the M42 main bearings (both use the same M10 x 75mm bolt from the factory).
ARP P/N: 201-4302 for BMW M50, 2.5L head stud kit can be usde for the M42 head.

As for injectors ill get it all built and working and dyno'd and if the injectors need improving ill do it then

Injector tune sell recon'd injectors for £15-£20 each and you are gauranteed to need them otheriwse you'll wear out the standard ones and the pump with a really high duty cycle and fuel pressue.

The brakes ill sort then i put it in an E30 would the suspension from a compact iv got the vented set think they would be big engough? or am i going to have to get the M3 ones? well it dosent matter yet as its only the engine im doing, the car wont be road or track legal for a long while...

What E30 shell is the engine going into? You could fit the compacts trailing arms to the rear and convert the front to E36 suspension (Phil_172 has done this on his V8 drift touring amoung others) you will be able to run 5 stud wheels. This will also give you rear discs if you have a pov spec E30 shell that doesn't already have rear discs From there you do have a few options for larger discs and standard calipers that can be found on higher spec models (not the M3 though as the hubs are different IIRC). Or if you stay E30 spec, Keri-WMS on here makes very nice 4pot brake kits with larger discs from 280mm upwards which would do the trick

[Minimayhem81]

Thanks for the part numbers. I will sort them injectors soon .

and as for the shell i really want to put it in to my road E30 which i have already done a brake upgrade off an touring, vented front discs and calipers and a rear disc conversion and because there off a touring i got told there slightly bigger then the normal E30 ones (dont know if thats true but hey)
But with me only being 19 dont think i can afford the insurance!

The other option is to put it in a ex PBMW race car which we bought last year witht he intention of racing it but we have descided to go for the E36 compact cup with the 750 MC and are currently building them.
So this means we have a road legal fully kitted PBMW which all its lacking to be a great car is power.... and better brakes.

So i believe thats what im going to do. Should turn out alright when its done. My dad wanted to do the 3.2 engine swap out of an E36 evo m3 but that will be a mission and there not cheap! so maybe oneday.

[rix313]

The touring calipers' pistons are about 10% larger than standard, looking to get a set for my race car.

Although the 3.2 is a big cost upfront, turbo projects can easily start to cost a small fortune you have to be strict. I started a Rotrex super charger build and spent a hell of a lot. I eventually called it a day as I still needed to spend more to get it perfect. To get the car running on low boost you should be able to do it without going too mad on internal engine mods. There have been a couple of low boost super charger builds which have seen over 200 and been reliable. I guess it all comes diwn to how good your donor engine is.

Is a chap called Alan O'neil one of your lecturers by any chance?

[Minimayhem81]

Yeah i can see how it could get costy...

Oh and as for the E36 compact cup this isnt to do with my uni i know birmingham city college is doing it but no my brother and i are racing as a progression from autograss

[rix313]

Ah right fair enough. Where are you doing the uni course?

[Minimayhem81]

Im at warwickshire college and i will do my final year at coventry uni to get my full degree

[Minimayhem81]

I would like to lighten the flywheel when i uprate the clutch during the enging swap... but should i try lightening the M42 flywheel or do a conversion to an m40 like were doing on the Compact's? All depends on what clutch i can get for its price...

[Alburglar]

I have m40 flywheel and it and clutch are more than capable of heavy use. They are dirt cheap, lighter, and a much better idea than the m42 dual mass one.

[Minimayhem81]

so sounds good, i think mine has a single mass but im not sure. but anyway m40 it is

[rix313]

If your M42 is a non aircon engine it's likely to have the E30 spec M40/M42 single mass flywheel fitted to it already, my 1995 one did. It's extremely hard to balance dual mass flywheels so most turn it away, waste of time any way. There's pictures of the differences in the sticky in this section

If you get the flywheel lightened make sure you take it to a engine specific machine shop so they have a true understanding of what they're doing then have it balanced.

If you wanted to do the low comp hybrid engine I suggested I have an M44 block you can use, only want £30 for it

[Minimayhem81]

Yeah i dont want anything to do with duelmass crap. Im not sure if it has aircon i will look when i go back to uni (its half term! ).
So either it has a single mass or it will get one, i can get a M40/42 four paddel plate rated to 241flbs or 328Nm.....
Im not sure what sort of power/torque figures i am expecting but i have also found one for an M20 rated at 215 to 228, max load 271flbs or 368Nm.
Finaly, i was just wondering if it was posiable to so how fit a M3 E36 set up its a 240mm 515flbs or 700Nm and a drive spline is still 29x10t... Has anybody fitted this before? as this would give me a good reliable clutch, capable of anything i throw at it...

As for the engine im going to get the set up working and them when i get bored i might try doing your surgestion as everything im buying will also fit on to the m44 block, i think

[Alburglar]

I imagine e30 m3 stuff would work, but no-one touches it as then the price of bits rockets!

[Minimayhem81]

Ok iv gone for the Helix 4 paddle clutch (271Lbft) this will do me for the dyno and then i'll have a think again when it goes on the road/track.

Does anyone know or have a link to the standard conrod sizes....?

[Alburglar]

Read the recent 2.0 build thread in this section. All info is on there

[rix313]

Ok iv gone for the Helix 4 paddle clutch (271Lbft)

How much has that set you back? When I was at college the lying b@stard at Helix said he'd sponsor us with a clutch after having a chat with him at Autosport, never saw it

[Minimayhem81]

£230 just for the plate, i havent got a high clamp load cover for it as they are £250+VAT, if i get toubles on they dyno i might invest in one... its the same plate as what were putting in the Compacts so we ordered three

[rix313]

Thats not bad like!

Any luck with finding rod sizes? That Metric Mechanic article says they're 140mm and I'd be inclined to go on that as they seem to know everything going on these engines. Why is it you need to know rod lengths?

[Minimayhem81]

Nope no luck, iv been looking at forged conrods (Cheap ones on eBay! FTW) want to check the length to make sure there the right things! haha

[rix313]

If you're changing them, strip your engine down and measure the ones you take out?

Is it the Polish or Greek ones you're looking at on fleabay?

[Minimayhem81]

American, my dads going over there soon so hes going to try bring them back with him save on the postage.

My dads picking up an engine i bought off here today so i'll strip that down and have a measure

[rix313]

You lowering the CR at all?

[Minimayhem81]

Yeah might have a go at machining them, I dont know what shape they are so dont know what im going to do to them yet . Got any surgestions?

[Minimayhem81]

Iv now bought a turbo and a DTA ECU its pretty old but will get me started....

I'll upload some pictures soon!

Iv been looking at intercoolers and i dont know which size to buy and unsure of where to mount it without major modifications... obvious place is behind the valance but i dout much air will pass through it... so was thinking of on the same shape as the rad' what are people views on this?

[appletree]

i have 2x of these in the shed. the S13 boy fit them as an upgrade and they also fit behind the e30 valanve and are alittle bigger than the rad, a few people have fitted them on here IIRC. i know toby_unna did for sure.

http://www.gumtree.com.au/s-ad/kensingt ... /360729618

Fits like this

http://media.photobucket.com/image/e30% ... 000115.jpg

Quite thin but flows well and good for 1bar boost

PM if your intrested

[rix313]

Matt I had a clear of the garage, I still have your Mk1 Rotrex bracket!

[Minimayhem81]

oh iv only jsut found these messages! it didnt light them up in my posts bit but oh well cheers for the offer though...

i was going to ask if anyone had the pin out for the m42 ECU and if posiable for the m40 too?? Thanks!

ps will put some pics up soon, its about time!

[rix313]

I have one some where I will dig it out!