Concise version of the M50 developments sticky

[rossmc88]

Hi,

Is there a concise version of the M50 developments sticky? Has most of the developments on doing a swap with an M50 not finished and there is a now "best" way of doing it from all the experimenting that has went on?

It would be amazing if there was a guide that detailed the best servo to use, prop and gear box combination etc? So you wouldn't have to spend 3 hours reading the 36 page topic?

Thanks

Ross

[Alex]

+1 there is far to many pages to read in that thread

[daimlerman]

Yes of course the thread has no end of twists and turns,those zoners who posted on it were the heros who pioneered the way to do the conversion by trial and error.
No end of times I have posted the spec. that I used,and that is completely different to,say, Danthe or Brian Moore's spec.
There is no 'right' or wrong' way,just the way that suits you,or the parts you have/can get hold of easily.
Things get a little more complicated the higher engine output you are considering,when you are thinking in terms of 250+bhp things like tieing the back axle down come into the equasion as well....

[DanThe]

As Malcolm says there are plenty of ways of doing the conversion, the way you choose obviously depends on parts available, funds and your own mechanical ability.

I think most will agree to the Clio servo being better than the Golf though

[rossmc88]

thats great to know the clio is the best servo to use. What is the best gearbox, flywheel, clutch, starter and prop combo to use?

[rossmc88]

thats great to know the clio is the best servo to use. What is the best gearbox, flywheel, clutch, starter and prop combo to use?

[mr_dink]

m42 gearbox is a direct fit and allows you to use a 325 prop with a sensible e30 ratio diff (3.7ish?) however some say that the m42 can't handle the power. Never heard of anyone breaking one though, even with a b28.

Using an m5x manual gearbox will mean it's man enough for whatever torque you want to put through it, but as it's a non overdrive box with a 1:1 5th gear you will need a v.low ratio diff (3.08ish?) and also a modified prop.

Flywheel, starter and clutch you can use any as long as they're all matched to each other, it's common to use a lightened m20 fly which would require matching m20 starter etc.

Anyone feel free to correct me on any of the above as I've never done the swap myself, planning to do so in the near future though so have read about many a swap on here.

[mr_dink]

Oh and also, m40 and m42 gearboxes are identical AFAIK, same part nos and everything.

[rossmc88]

ok ill go for a m42 box, m20 starter clutch and flywheel, and 325 prop. Does the m42 box have any gear linkage alligment issues? I want to go for whatever combination is easiest and takes the less amount of modifying. An m42 box would do me because i dont ever plan on running more than the standard m50 power. What engine mounts and air box should i use?

[mr_dink]

m42 box lines right up it's the m20 box that sits at an angle. Not sure exactly which selector rods you'll need to get the gearstick sat right but I think it's 320 ones.

You need e36 alloy engine mounts and e28 m5 rubber ones.

m42 box should be fine and requires less modifying and no funny diff ratios.

It's all pretty much bolt on stuff except for the exhaust manifold.

[DanThe]

Lightened/balanced M20 flywheel/clutch is a good mod to do before the lump goes in. Standard M20 flywheel will need some machining on the rear to fit, or you can grind some of the sump webbing back to fit the standard one

[daimlerman]

When the stock M20 fly is offered up to the block you can see what needs the attention of Mr Angle Grinder.
M40/M42 'box is fine for standard M50,you will need 320 gearstick mount and selector rod,or be a competent welder in light alloy....to shorten the M40 items!
This is a good chance to install the Z3 1.9 gearstick for it's shorter shift.
E36 engine loom is longer than E34 so easier to modify,Dan supplied mine for modest cost ready to fit.
Exhaust is the other biggie,you will need to be a competent welder/fabricator to modify M52 s/s manifolds to clear the steering rack and the ARB,there is no cheap ready made solution.
I started with a 3.45 diff,but found it too 'tall',the current 3.64 gives better acceleration with the same overall fuel economy.
Prop should be the longer E30 one,not the special short thing fitted to 325i when using the M40/42 'box.

[DanThe]

That reminds me, must must get over to the gear manufacturer for quotes on steering linkages

[daimlerman]

That reminds me, must must get over to the gear manufacturer for quotes on steering linkages