Prop-shaft for S50B32 swap using 5 speed boxÃ¢â‚¬Â¦

Post Tue Jun 20, 2006 1:04 pm

I'm currently sourcing the parts for my S50B32 swap as many of you will know (I say it a lot, just don't do it!)

The engine and running gear I have is from a 1997 M Z Roadster and as such has a suitable diff and a 5 speed gearbox. The prop-shaft that came with it is unfortunately prop-shafted but I may be able to rescue it or parts of it (when the accident happened it was pulled apart which spun the tips of the splines off where the collar nut is in the middle, I could dress them and try to fix). It looks the right length as the Z3 and the E30 share a lot in common (wheelbase??? Ã¢â‚¬”a Engine to diff distance??, not sure). I don't know if it'll be exactly the right length and may need shortening/lengthening but here's to hoping.

In the event of me having to find an alternative, can anyone think of my best course of action? The gearbox that came with this engine seems a little bit of an enigma. I assumed it was the same as an E36 3.0 Litre M3 but a friend who has a limited knowledge of these said it doesn't look quite right. The output flange looks bigger than my E30 one as does the input flange to the diff.

Can any of you ETK wizards help me here? Are there any E36/Compact/E30M3 etc props that I can use? Hybrids (front of E30 rear of MZRoadster as an example) are a possibility.

I hope that made sense and I hope you can help..

Many thanks either way.

Jai

Post Tue Jun 20, 2006 1:21 pm

Ive just checked the ETK and the rubber donut is the same on the '97 M Z Roadster and the E36 M3, so the E30 M3 prop will fit to the MZ 5spd box.

The MZ prop could well be the wrong length (or it could be right

) - the ETK shows 1240mm, but it doesnt show the E30 M3 prop length

I can try to measure my E30 M3 prop in a few days when I get the car moved and see how far out 1240mm is.

Fixing your MZ prop maybe an option, but it would need to be rebalanced if its been apart, unless it was marked before. Its possible that any damage may also throw it out of balance.

Post Tue Jun 20, 2006 2:15 pm

Thanks for the help fella!

I dont think I can use an E30 M3 prop unless I get a different diff. Not 100% but the input flange to the diff seems quite a bit bigger than the E30 one. My E30 M3 4.1 (american) diff has the same flange as the small case that came off my 318is so I'm assuming the 3.25 enlish diff is the same..Sound right?

Thanks again.

Jai

Post Tue Jun 20, 2006 2:19 pm

I thought the ZM diff was an upgrade/another option for those who need a 3.15 diff - like us S50 converters. I was on the look out for ZM diff for mine because of the slightly longer ratio and better Slipper.

Post Tue Jun 20, 2006 2:28 pm

You could well be right. It looked bigger but that may be because the flange is round rather that convoluted if you get me (its a full circle for strength instead of the funky X shape of the E30 diffs).

I hope you're right cos I may be able to just buy an E30 M3 prop!

The Torsen slipper does look handy, smoother and more progressive. I have to replace the finned back plate though, mine was damaged and the drivers side flange lost. Car was rather battered. The guy went sideways into a bank at 120, flipped up and hit the boot SQUARE on into a bridge. NOT pretty.

Jai

Post Tue Jun 20, 2006 2:37 pm

Im sure thats right about the ZM diff. I know what you mean about flange shape, but that shouldnt be a problem as long as the bolt holes line up.

jaistanley wrote:Car was rather battered. The guy went sideways into a bank at 120, flipped up and hit the boot SQUARE on into a bridge. NOT pretty.

Not good, hope he was ok.
Makes the E30 conversion ever more interesting

Post Tue Jun 20, 2006 2:40 pm

There was a bloke swapping an S54 into an E30, all he did was use the E30 rear section with an Automatic E36 or E46 front half, the splins were the right size so it just pushed together, i'll see if i can find the link but it will take you a long time to wade through the thread because it's massive !!!

Post Tue Jun 20, 2006 2:47 pm

Cheers guys...

Err.. the driver wasn't OK.

A guy from work's sister used to go out with him. He is an ex beemer driver unfortunately. (my respect to anyone who may have known him). Didn't have a seatbelt on, the hood looked like an ejector seat had gone off.. Reminds us all to drive safe and belt up. The passenger did and is fine (I'm told).

Jai