m43 318i 2.1l rebuild

[steve_k]

allrighte peep's?

as the title really,

my mum's B/F has asked me to try & find out about the above .

he's got a m43 318i lump & has heard about taking it out to 2.1 & like i said has asked me to find out if it's possible & what parts would be needed.

T.I.A

steve.

[rix313]

PM odbod he's doing a stroker at the moment and is getting some adaptors made up to modify a rover crank to fit the BMW block.

[Omi]

Why not swap for an M44? The extra 8 valves, 1 camshaft and simplicity of the swap, rather than rebuilding a motor's internals for some gains at massive expense...

Presuming you're talking about an E36 here, there's loads of Compacts with M42/44 lumps in scrapyards. - Bolt on, for you. Much cheaper, power gains, and a better platform for further modifications.

[Bob_S]

why not just put an m50 in?

[Omi]

Why not an S50?

[Bob_S]

with a turbo.

[Omi]

With NOS.

[Bob_S]

with hydrogen injection.

[Omi]

With hydraulically actuated valves to allow completely custom timing without cams, offering the choice of running on less cylinders, and the further option of water injection to create a 2nd power stroke.

[Bob_S]

with this done, he should then transplant it into an e30 318is shell which is made of unobtainium and then galvanised and is thus far lighter and handles far better than any other car on the road, bar none.

[Omi]

Surely then you'd just leave the M42 in-situ, rather than messing around with all this Formula 1 and cutting-edge performance technology?

Gordon Murray only used the S72/2 in the Mclaren F1 because BMW did him a good deal... He originally wanted M42s when he phoned up.

[Bob_S]

usually most iS' have exceeded the 100k mile life expectancy and now require the chains to be changed as they are prone to snap!

[odbod]

If you really want to do this start with a reasonable M42 Engine, get some S50 pistons and a rover crank, I can arrange to get it modified to suit and hey presto, with a bit (quite a lot), of extra work you have a 2.1l engine. The engine block will need to be bored out and I think you might need some M50/S50 135mm rods, but I'm not sure, M42 rods are 140mm.

Alterntively quote a lot of work can be cut out using an M44 engine and an M42 Head, + rover crank shaft (again modded to suit) to give you a 1997cc 2Litre engine. Going down this route means you can use the M44 block and pistons, the pistons need ~ 2.5mm shaving off the top of them.

The rover cranks are some what limited on time, there are some going through very soon, after that I don't know, you need to supply a crank from the BMW engine used in the Rover 75 or freelander, 88mm stroke, non balance shaft engine type, and £200 to machine it so it is a direct fit in the M42/M44 engine block.

If you are keen drop me a pm you'll need to lay your hands on a crank in the next week or so, there are some on ebay, but quite expensive (£180), the alternative is to get one from a breakers, some have found them for £60...

I wouldn't bother with the M43 route, best go for 16valves

Cheers

[steve_k]

cheers for that.

i'll ignore the daft idea's & talk to him whrn i see him next.

[Omi]

Ungrateful swine.