supercharge the M42 or an M52

Post Mon Jul 07, 2008 1:43 pm

I need some advice because i can't make a descision. Here is the situation - help me please guys.....!

I have a perfect bodied 318is, it is off the road minus it's engine at the moment whilst it is polybushed and a few other odds and sods. The plan was to re build the engine and supercharge it - similar to what appletree has done - i even have the supercharger and some more bits and pieces.

My only problem is having just bought ny first house (not much money) and needing to replace my daily driver which is quickly falling appart. I have been considering an M50/52 swap. What do you all think? I think M52 would be cheaper given i was planning to fully rebuild the m42 engine.

i know the IS people will kill me for even thinking of putting a 6 pot in it

So please offer me some thoughts.......!

Cheers, Daf

Post Mon Jul 07, 2008 3:31 pm

The M50/M52 swap is fantastic. I'd seriously urge you to do that before thinking about tuning. A supercharged one will be fantastic. Yea the iS engine is good but if you can afford a bit of extra fuel and a bit of extra insurance you can't beat that extra displacement.

The M52 really isn't that heavy either. Yea, you'll need hefier springs but that's about it.

Post Mon Jul 07, 2008 3:37 pm

M52 aaaaaaaaaaaaall the way

I have an M50'd e30 and its fun. M52 is just the same again but more fun

Post Mon Jul 07, 2008 7:40 pm

Thats what I'm begining to think - how much should i be looking at to do a full m50 or 52 conversion? I have no idea???

I have priced up all the bits i will be needing to finish the charger and if my bank manager knew he would be having sleepless nights!

insurance isn't an issue, and i'd like to say neither is fuel - but with current prices i'd be lying!!

What would the wiring be like to achive? I am confident i cold make anything mechanical but electrical knowledge is pretty basic!

Cheers

Daf

Post Mon Jul 07, 2008 8:31 pm

I did an M50 conversion for a Zoner recently, was a fairly standard spec conversion and didnt cost much over £1,000

Most parts were bought at bargain prices though

Post Mon Jul 07, 2008 8:36 pm

Now thats a healthier figure than what i was totting up in my mind for supercharging and rebuilding the M42!

Anyone interested in swapping an m50/52 for an m42, a supercharger and a few bits and pieces let me know!

Would it be a good bet to try and find an accident damaged e36?

Cheers

Daf

Post Mon Jul 07, 2008 8:43 pm

I dont know about M42 bits, but im sure I could find you a load of M50 gear to swap for hard currency

Post Mon Jul 07, 2008 8:55 pm

My conversion cost a hell of a lot less than 1k

Post Mon Jul 07, 2008 9:06 pm

How much should i be looking at for an engine? there is an m52 on egay for £699 but it doesnt really come with much!

it seems a complex conversion because there is so many different ways of doind it!!!! all sorts of options for boxes, mounts, wiring!! is there a 'best' way?

Cheers

Daf

Post Mon Jul 07, 2008 9:10 pm

No best way.. There are many options, all just different ways of doing it tbh

Post Mon Jul 07, 2008 9:10 pm

there is a B28 on e36coupe forum for £400 atm, complete and can be heard running

Post Mon Jul 07, 2008 9:13 pm

Jhonno wrote:My conversion cost a hell of a lot less than 1k

How much were those manifolds again Mr Jhonno?

Post Mon Jul 07, 2008 9:15 pm

I only used them as I had them laying about, otherwise I'd have gone with the 'free' option

Post Mon Jul 07, 2008 9:20 pm

DanThe wrote: How much were those manifolds again Mr Jhonno?

Post Mon Jul 07, 2008 9:28 pm

pardon my ignorace, but being a 4 banger peson whats a B28???????

cheers

Daf

Post Mon Jul 07, 2008 9:31 pm

http://www.unixnerd.demon.co.uk/bmw.html

Click on 'E and M numbers' on the left of the page and you cant go wrong

Post Mon Jul 07, 2008 10:08 pm

DanThe wrote:
DanThe wrote: How much were those manifolds again Mr Jhonno?

Shhhhhhhhhhh!!

Post Tue Jul 08, 2008 1:16 am

With a carefully constructed steering coupling you can get away with using standard E36 M52B28 or M52B25 manifolds it seems... (that's with a STD E30 steering rack I believe).

As a guestimate, using an M42 flywheel/clutch/gearbox/diff/radiator etc that you already have you could drop an M52B28 in for the price of a smaller servo, electric fan, 5 Series sump, and a few other odds and sods. Not much at all! Of course you'd want to drop something like a 3.62/3.73 LSD in there too...

Post Tue Jul 08, 2008 1:56 pm

Could be a problem there because i'm running a lightened 325 flywheel, e21 release bearing and325 clutch in my 318is!!!! I weighed in the old m42 dual mass flywheel!

Never mind - the grand total is almost certainly less than that of a charger!

I am not sticking with the std e30 rack though - i live in wales with all those lovely bends, be needing me a z3/e36 rack for sure! Does this cause any issues with the manifold clearances?

Cheers

Daf

Post Tue Jul 08, 2008 2:30 pm

Quite possibly, but if you make a narrow steering coupling I doubt you'll have to remove much from the rear manifold to get it to fit.

I don't think there's any reason you can't fit the flywheel/clutch combo you have to an M50/52. You have to remove some of the aluminium ribs on the back part of the sump but it's no big deal. I think you have to use whatever starter motor you are currently using too.

Post Tue Jul 08, 2008 2:38 pm

you can use that flywheel etc setup on the M52.. Depending on where it was lightened dictates whether you have to shave the back of the sump or not

Post Tue Jul 08, 2008 9:20 pm

i'll see what i can source though because my gearbox is showing signs of wear! would anybody recomend a particular gearbox/flywheel-clutch/prop assembly that is best - or is it just a case of what you can lay your hands on for the correct price?

Cheers

Daf

Post Tue Jul 08, 2008 9:31 pm

Well I'd say the ZF box used on the 328i, MCoupÃ© and the M3 3 litre are the best. That'll need you to use either a 328i prop with an E30 centre bearing or an E30M3 one. Then you'll need a diff with a ratio of around 3.15.

You could use the early E36 325i Getrag gearbox, you could use the E30 325i prop then but you'd still need the lower ratio diff.

The cheapest option is that mentioned above, the M42 gearbox, prop and an E30 ratio diff.

You can use the ZF 6 speed box from the M3 Evo E36 but that requires custom prop and gearbox supports.