Ratch's 318iS Resto is back!!!

[Ziggy]

What's the craic with building a 2.1 M42?

[tim_s]

m42 with m44 bottom end? Built one of these before with kent regrinds, 161bhp, runs like factory. m44s complete are also a good move though having said that, just the end result is a bit more factory with a hybrid m42/4. What symptoms have you got? If it's just profile gasket and it's not overheated, prob only a few hours to see it right...

[Royalratch]

Researched it, love one but put off by everyone that they're a disaster waiting to happen and cost as much as an M52 install almost. Love the idea of one tho.

[cro320]

Yeh but you can't see from the pix that it's a fake! And I don't have a refund!

Cheers tho.

I have the same rear blind! It's not fake, it's dealers retrofit

[Royalratch]

Aha!

All dealer retrofit 'options' are fake lol.

[Felix79]

Ratch why not go for an s14?

[B7]

Ratch man! I cannot believe you are even contemplating a step away from original......

Do not let the OEM Homo side down!!!!

[tim_s]

I still think m44 or 2.1 would be nice - sort of OEM+ - externally unchanged but 'honed' from the original. that or just bend over and buy an s14!

[goosiegander]

S14 (in this case) ftw!

[Royalratch]

S14 is a no no. Terrible engine for town driving. A constipated driving experience under 4K rpm.

OEM+ is okay. I think a solid headjob with some cheeky porting and a skim or M44 FTW.

My sense has returned!

[bss325i]

I've never slagged off the 6-Cylinder boys - only the M20 boys.

I cant see my 325i M20B25 head cracking at 130k if at all.

Dont be a big gaylord, M52 FTW!

We both know it makes sense. You wouldn't even be thinking about it otherwise!

Keep your M42 in the shed if you ever get the inclination to revert back to original but limp wristed gayness.

[Simon13]

Barry just wants your money. Don't listen to him. OEM+ 2.1 M42.

[Royalratch]

But 2.1's are almost universally condemned. Too much thrust angle on the conrods at BDC or whatever causing rods to go.

Longer stroke means more torque tho right?

[Jhonno]

I've never slagged off the 6-Cylinder boys - only the M20 boys.

I cant see my 325i M20B25 head cracking at 130k if at all.

Dont be a big gaylord, M52 FTW!

We both know it makes sense. You wouldn't even be thinking about it otherwise!

Keep your M42 in the shed if you ever get the inclination to revert back to original but limp wristed gayness.

[bss325i]

Regardless of who does it (as long as they do a good job!), M52 is the way forward!

I think DanThe does drive in drive out conversions.

[Dezzy]

I can't see Ratch asking Dan to fit an M52 for him or Dan doing it tbh.

You couldn't have it done better anywhere though.

[Royalratch]

Nah, staying 4-Pot twin cam FTW.

Maybe some other juicy tweaks tho like some mild porting to the head and a remap - all invisible but good for another 1bhp.

Still need to get a minty 4.10 LSD sorted (USA this Summer for that!) and maybe 8J's on the rear.

[bss325i]

11121739913 $2,144.49

[Royalratch]

Lo mileage M42 / M44 - £350.

BSS Engines Ltd fitting service - ?

[bss325i]

Dont bother with an M44. If your going to stick with a four pot then stick with an M42.

Good luck finding a low mileage engine though.

New head.

[Kedge]

OEM+ 2.1 M42.

[e30topless]

Frag the shitter and buy a sport !










sorry fella I couldn't help it, as much as i despise the M42, your car isn't a rotting scrapper and needs to be kept OEM

[johnt0709]

OEM+ 2.1 M42.

Give him 2 years and he'll be chillin with Bootyman.

Oem+ FTW

[tim_s]

But 2.1's are almost universally condemned. Too much thrust angle on the conrods at BDC or whatever causing rods to go.

That's bollocks! M42 Haterz! When you say universally condemned, by whom? why?! Rod ratio on my 2.1 was far, far less than your run of the mill 330ci or whatever. Not to mention it had cracked rods and arp rod bolts to hold it all together. That engine's had plenty of miles and track days/ring trips. Obviously there are different rod length/piston pin height combinations etc that can be used and that will dictate the rod ratio, so I guess it does ultimately depend on how it's been built. But I just don't see any evidence for what you're saying, seems more or less totally unfounded.

Longer stroke means more torque tho right?

Mine made more than the peak torque of a 1.8 m42 from 2k rpm to the redline at 7,4k, over 150 ft/lbs from 4,5k rpm and a peak of 175ft/lbs. So yes

[tim_s]

Dont bother with an M44. If your going to stick with a four pot then stick with an M42.

Good luck finding a low mileage engine though.

New head.

haha you're going to get loads of differing opinions here - I reckon the m44 or m44 hybrid is the best route. Barry, why not m44? standard they're quieter and faster than the m42, and most of them are half as old and it's easier to find low mileage examples. It's not too much work to fit them to the m42 ecu etc. My personal pref would be m44 block, m42 head which is externally identical to factory. Almost all M42 blocks now have rusty coolant channels, have done loads of miles and are 20 years old. For a couple of hundred quid with an m44 you get bigger capacity which in the one I built was good for 161bhp on an m42 head with £200 kent regrinds with more torque throughout. They've made lots of improvements like better lighter cracked rods too. The crank stuff is overrrated, the m44's one isn't as nice as an m42 one but is lighter and in reality for a road car they're the smart choice.

[Royalratch]

Tim.

A few people on here have said they have had stroked M42's come in with the same failure. I think M44 is the way to go but the issue I had with the one in my Touring was the M44 using single sensor to feed the ECU and Temp Gauge whilst the M42 uses 2 sensors. So you where do you put the Temp Gauge sensor on the single port M44 block - assuming the M42 ECU will use that port as a priority?

2.1 could be a go-er but I'd probably build that engine outside and drop it in. I've been building my bike engine up so am getting my head round valve clearances, valve seat lapping and custom pistons etc etc.

Forged 810cc goodness FTW.




Tim, jog my memory on a 2.1 - all stroker, with shorter pistons, N47 crank etc etc? No boring?

[tim_s]

Oh right, have other people on here built one? I've not seen any other strokers on here! My 2.1 was 88mm stroke (m47), and pretty big overbore of 3mm to 87mm with some tasty forged goodness for pistons! Needs custom MLS gasket - but these are a better idea anyway. you can go 90mm stroke but makes piston pin height/rod length more tricky plus I'm totally happy with the near square engine.

On m44s, the temp sensor thing among other things (such as top timing case slightly different on m44/m42 and you need to use the m42 one to get the cam sensor on the correct wheel etc to do it right and use a bit of instant gasket to seal it up) is why I prefer doing the m42-everything-with-m44-block hybrid. If not, the temp sensor thing is easiest resolved with a T piece or just feed the dial from somewhere else by teeing into a hose, but obviously if building a hybrid you don't even need to worry about that as you'll be using the m42 head. The other reason I like doing the m42/4 hybrid is cam availability for the m42 head is better. The late 6mm m42 heads off later m42 e36s with the single valve springs are prob the best heads imo.

[Royalratch]

So it is bore and stroke.

What can you achieve with bore only - worth the bother?

[tim_s]

Just bored you could get 1925cc max and get a nice high CR - not a bad idea imo. with a short stroke would be pretty revvy. Could do the same with an m44 and get 2l. Both ways you'll need an MLS HG.

I think basically you need to work out if you want to just do an oem rebuild - in which case an m44 with kent cams and new clutch/light f/w would be the ticket and feel a fair bit quicker, or go a bit mental, in which case doing something similar to the one I did woudl be the way forward - being a bit more mental than me (I kept mine very daily driver and decided to stop chasing power as I had enough) I reckon there's 220-230bhp in there.

[Royalratch]

200bhp would be plenty - and I'm all about town posing with the odd blast so usability is key.

What I don't get is how a 2.5 M52 only gets about 195 with some mods - surely it should be making more.

Food for thought.

[Dezzy]

2.8 M52 Ratch

They are heavy restricted on the inlet side. M50 inlet and tb see them well over 210bhp and a set of S52 cams and a re map see them around 250.

[Royalratch]

Yeh but these M5x conversions are getting awfully common.

Soon they'll be so widespread they'll be positively council.

I think an enlarged M42 is the way to go. Unique, decent power hike and invisible to all - especially the insurance man.

Watch this space.

[tim_s]

A 250bhp 2.8 m52 would have to have some pretty extensive mods I'd have thought though, not just inlet, cams and remap. 90hp/litre from a 10:1 CR m5x with single vanos is a lot! US s50/s52 make about 80hp/l and they already have everything mentioned there not to mention more capacity. My alpina B3 is a 3l 10.5:1 (iirc!) with cams, zorst + manifold, alpina tuned etc, same if not modded cyl head (I don't actually know!) and manages 83hp/l. Not saying it's not possible, but without opening the engine up, raising CR and adding some pretty spicy cams, seems a pretty optimistic figure.

[Dezzy]

There has been a few with better (proven) power than 250 bhp.

One dyno proven 260 bhp with S52 cams, enlarged tb, M50 inlet manifold, exhaust and live remap.

They are very restricted as standard

[Royalratch]

I'm already in negotiations for a clean E36 M42 head.

PM'ed you Tim if you'd be so kind.