M42 Tuning

[pac1982]

Looking in to tuning options for the M42 engine, i have a 318is and would like to get a little bit more power out of it.

I'm guessing it has quite a bit of potential seeing as the E30 M3 engine is based on the M42 and also having seen the engine in the E36 touring car which puts out over 300bhp also based on the M42 engine.

Having said that i'm not after massive power but between 160-200bhp would be nice.

What would a few basic things do for me such as a full exhuast system and superchip?

And please no comments like "Just drop a 325 motor in"

I was reading something on wiki about using pistons and a crank from other BMW motors but not sure how true this is seeing as anyone can write stuff on wiki heres the quote from wiki......

"Further, the long-stroke forged crankshaft from the M47 motor coupled with an overbore of +2 mm will make for a 2.1 L Stroker M42. The 86 mm pistons from a European 3.0 L S50 will produce a high compression, stroker M42 when coupled with the M47 crank. The addition of a MAF conversion from an M50 engine and properly setup cams, valvetrain, and tuning will yield potent output from the M42. "

Any help at all would be great

[stonesie]

Have a good search around this section, there have been strokers built and pushing out about 200bhp and there are a couple of supercharged engines pushing simmilar power (appletree and Hoshy spring to mind)

But please clear your mind of any link between the M3's S14 engine and the 318is's M42

[appletree]

A full exhaust an chip with a big bore throttle body would help but doubt you'd get your 160bhp out of it.

The wiki stuff is right, an m47 stroker would get you someware around the 180-200bhp mark but its not cheap to do properly. As N/A tuning is expensive compared to FI

[pac1982]

I would love to go down the turbo route but where do i get the parts from, dont mind spending the money i'm guessing it would cost about £1500-£2000 for the conversion but what are the end results like?

Would i be better of putting a 325 engine in?

[Daf318is]

I looked in to all sorts of options with tuning my M42 ranging from stroking it to charging it, I even bought a charger and started making mounts! But when I started adding up the costs it just wasn't practical - i know you say no comments about dropping a 325 in - I'm just warning you that costs can escalate and a conversion is far better value for money!

[Elecblondie]

I'm guessing it has quite a bit of potential seeing as the E30 M3 engine is based on the M42

Really? Pretty sure the s14 has its roots in the m10 with a head derived from the m1's engine.

[Alex]

m20b25

start with a chip and bbtb, i chipped mine the other day well worth it

[appletree]

If you want a quick easy solution that will give you the power you want with scope to increase power in the future then dropping a b25 in would be the best bet.

Think you'd be looking at 2k for a stroker depending on how much you get a crank for.

An then you would be about asfar as you could go power wise.

[ShakeyC]

I'm guessing it has quite a bit of potential seeing as the E30 M3 engine is based on the M42 and also having seen the engine in the E36 touring car which puts out over 300bhp also based on the M42 engine.

I think your being fed porkies mate

N/A is lots of money really if you haven't got spend then strongly advise leave it alone and just give it a damn good service and maybe a chip! Last thing anyone wants to do is spend cash on quality or branded parts here and there which ends up being miss-matched thrown together ending up rubbish!

Personally i would not stroke an M42 fit some solid lifters and good cam profiles with a good chip, what you can't beat in CC you will in revs

[pacerpete]

I would love to go down the turbo route but where do i get the parts from, dont mind spending the money i'm guessing it would cost about £1500-£2000 for the conversion but what are the end results like?

Would i be better of putting a 325 engine in?

YES !

[hongkongfuey]

i'm sure an old zoner (koz) i think it was had an 'is' , can't properly remember but sure it had, bbtb, cam upgrade, chip, and was running at 162hp, it was in either pbmw or total bmw

[GrindCulture]

M50 it. 6 pots + 4 valves per cylinder = Proper engine

[ShakeyC]

M50 it. 6 pots + 4 valves per cylinder = Proper engine

But but but it sounds like a dyson

[Daf318is]

M50 it. 6 pots + 4 valves per cylinder = Proper engine

But but but it sounds like a dyson

You must have one hell of a problem with your dyson mate!

[robbo86]

i'm sure an old zoner (koz) i think it was had an 'is' , can't properly remember but sure it had, bbtb, cam upgrade, chip, and was running at 162hp, it was in either pbmw or total bmw

Kos. DOnt think it was recammed, but it had a remap

[GrindCulture]

162bhp with only mild breathing upgrades and a remap seems a bit optimistic for a 1.8 M42 to me. With a 1.9 bottom end it would be so much more believable IMO.

[odbod]

Dunno about £2K for a stroker engine, depends what you want to do...

Thetomc is using an M47N crank (89.6mm stroke) to build a stroker using standard M42block and pistons and some M5x 135mm rods with an different head gasket to get about 2L.

I'm getting a M47 Rover crank (88mm Storke) modded and using M44 standard block and pistons skimmed down so they don't hit the head, other than tha the engine will be much as standard to get a 1997cc engine. But I'm lucky as I can get some very good deals on machining...

Both options should get to 170bhp+ one way or another, whether you go forced induction or N/A you will have to take the hit on some engine management.

[appletree]

I was thinking about the cost of a M47 crank, euro m3 pistons and machining work with some one that could do the work them selves, or mod a rover crank, to get a new crank was £816 when i last spoke to bmw.

[odbod]

Yep, I'm running with the modify a Rover crank that someone sold me for £60 (cheers Appletree ) idea, then with the £200 M44 engine I've got a set of pistons that match the bores and once skimmed will be just about right for a budget build spec, but still giving enough of a step up in terms of performance. That with the PCIII that I bought for £130 gives me enough control to get it running right. And having just finished my LPG install I'll be running at diesel economy too.

After that I've just ot to sell everything else and should end up relatively cost neutral, maybe £300-500 cost for the engine tops once I've bought all the gaskets etc...

[armanib]

http://www.noswizard.com This may help

[odbod]

But the AA says everyone that uses NOS is going to die!

[GrindCulture]

It'd be interesting to see how a little M42 would cope with nitrous, but I'd be buggered if I was the one who was "testing" it, unless it was fitted by someone who really really knew what they were doing.

[Gunni]

Power usable from NOZ is just the same as from a SC or Turbo.

Stock internals are good for 300hp EASY.

[rix313]

But the AA says everyone that uses NOS is going to die!

That made for some very irritating morning TV

[pac1982]

But the AA says everyone that uses NOS is going to die!

That made for some very irritating morning TV

I heard that on the radio made me chuckle!

I had NOS on a Lambretta once