M3 wheel hub and bearing

Post Sat Sep 15, 2012 6:44 pm

just a thought

Is the axel size different on the e30 m3 to the rest of the e30 range? and if it is is it bigger?

If its the same size could you not fit an e30 m3 bearing / hub to convert to a 5 stud?

If the axel is bigger sureley you could get a sheith made to a push fit over the standard axel to build it up to the m3 bearing size?

Post Sat Sep 15, 2012 6:54 pm

From memory not a chance for the front bearings however the rears are the same size as standard 4 stud and the trailing arms are the same as well. You will however need calipers and carriers from an m3.

Post Sat Sep 15, 2012 7:25 pm

At 300 quid a side you may as well source front struts and rear arms

Post Sat Sep 15, 2012 11:04 pm

Or if you don't have abs, use an e28 bearing for about £30

I very much doubt it's as simple as
Bolting them on, probably a similar problem to you get if trying to fit e36 hubs onto an e30, the stub axel isn't long enough to fully thread a nut on.

Plus you'd then have to mess around finding disks to fit, space te calliper to suit etc.

Post Sun Sep 16, 2012 12:13 am

What's the reason for a 5 lug set up ?

Post Sun Sep 16, 2012 4:05 pm

Kos wrote:What's the reason for a 5 lug set up ?

brakes im running 740 calipers on 320 mm disks with 16" wheels and the calipers have had to be ground down to fit under the 16" rims im wanting to upgrade my calipers but not wanting to grind them down to fit under the wheels so new wheels it is, and there is a much begger coice of wheels in the 5 bolt pattern

Post Sun Sep 16, 2012 4:45 pm

IIRC 300mm.de did a conversion kit a while back that was simply a sleeve to go over the e30 stub axle & the hubs/bearings.

Post Mon Sep 17, 2012 12:00 pm

steve_k wrote:IIRC 300mm.de did a conversion kit a while back that was simply a sleeve to go over the e30 stub axle & the hubs/bearings.

I've seen this done on a Dutch forum also, I'll try find some pics

Post Mon Sep 17, 2012 12:22 pm

Jozi wrote:
steve_k wrote:IIRC 300mm.de did a conversion kit a while back that was simply a sleeve to go over the e30 stub axle & the hubs/bearings.
I've seen this done on a Dutch forum also, I'll try find some pics

thing is if this is possible & proven to be safe then i'm suprised more folk ain't doing it.

jozi, if yyou find the link post it up & (fingers crossed) it may can contain the dimensions of the sleeve & if so i've got some old coilovers i'm going to rebuild & try it out

Post Mon Sep 17, 2012 12:29 pm

No dims but that shouldn't be to hard to figure out, E30 OD and then the ID on a e36 hub. Found a few pics anyway:

Standard brakes won't fit anymore either, you'll need adapter brackets and callipers

Post Mon Sep 17, 2012 12:31 pm

Cheers for that jozi

time to get the tape measure out lol.
could make 5 stud conversions a little bit easier.

Got hi-spec 4 pots so no worries about brakes lol.

got a link to it?

Post Mon Sep 17, 2012 12:38 pm

steve_k wrote:Cheers for that jozi

time to get the tape measure out lol.
could make 5 stud conversions a little bit easier.

Got hi-spec 4 pots so no worries about brakes lol.

got a link to it?

It's in Dutch though http://www.e30fansite.nl/Forum/viewtopi ... a&start=50

2 sleeves for 45 euro need e36 hubs then.

Post Mon Sep 17, 2012 12:39 pm

Cheers jozi.

google translate will be on it later.

cheer's for that

Post Mon Sep 17, 2012 12:43 pm

Let me know if you need any help translating

Post Mon Sep 17, 2012 1:32 pm

Jozi wrote:Let me know if you need any help translating

Thanks dude no worries ;)

Post Mon Sep 17, 2012 5:36 pm

From memory, there was questions over how much thread was available for the hub nut, once the sleeve was in place.
I'm sure a member on here tried this, but decided against it as he wasn't happy, I think with the hub nut issue.
This is all from memory, so might have it wrong.

Post Mon Sep 17, 2012 5:42 pm

You can see from the pics above the nut doesn't go all the way on, and theres certainly no way you can strake it into the axel.

I personally wouldn't be happy running my own car like that.

Post Mon Sep 17, 2012 6:06 pm

harry_p wrote:You can see from the pics above the nut doesn't go all the way on, and theres certainly no way you can strake it into the axel.

I personally wouldn't be happy running my own car like that.

+1 That looks like a accident waiting to happen.

Post Mon Sep 17, 2012 6:06 pm

MIght not be difficult to bodge another method of securing the hub nut though. Difficult to see for sure but it looks like there maybe enough thread for safety so a bodgeworthy castle nut arrangement could work.

Post Mon Sep 17, 2012 6:12 pm

Surely the risk would not be that the nut would come off due to undoing, I would think with that little thread in the nut the risk of it stripping the threads out of the nut/axle would be quite high.

Post Tue Sep 18, 2012 4:32 am

Funny this should rase its head now, i am currently working on a similar set up to what is shown above, however it will have proper bearing location and full thread engagement with a method to lock the nut similar to the stock set up.
I actually have a strut converted Sat in the garage as i type this, the issues that need to be resolved as said above are of the brake fitment as there are issues with both caliper mounting and rear clearance for back plates and track rod ends.

i am looking at a combination of hub spacer and special nut, a caliper bracket for e30 calipers on either 286mm or 300mm discs and a hub centric spacer for the back of the disc to give suitable clearance.

However there is no simple solution available currently that is safe. And that's the big critical with this, simply using a sleeve and the stock nut is a big no no.
Any solution coming from the direction will be a little more complex/expensive than that option but will be a proper safe solution or i won't put it out there.

Perhaps its the right time to ask what a properly engineered solution should be priced at? As if i can't do it safely for a price people will pay then there is no point proceeding.
Is £350 too much for:
300mm discs
5 stud hub
Adapter and nut
Caliper spacer
Disc spacer
Long studs
Pretty much a bolt on kit for both sides.

Post Tue Sep 18, 2012 4:38 am

Just to add a few issues i have found with the current versions are the thread engagement, the ability to lock the nut, the location and in a couple of cases the compression of the bearings, the brake issue, the abs sensor depth and the resulting wheel offset.

It seems getting the hub on there is as simple as a sleeve but the rest needs a bit of work if a bodge is to be avoided.

Post Tue Sep 18, 2012 8:15 am

@hairyscreech.

if like you say a safe way of doing this is possible & is proven to be safe then a price of £350 would be fair to pay for such a conversion.

like you i'm in the process of trying to find a solution & not a simple bodge & although it might take me some time i'm sure that either of us could come up with it.

mine mite just a bit more heath robinson than your's though, & please don't ask me to explain it as I can't lol, I just get on with it.

Post Tue Sep 18, 2012 3:08 pm

Here is a preview of what i have (currently made in metal) but i don't want to reveal too much at this stage as it would be very easy for someone to copy/steal the idea.

As can be seen from the CAD drawing the nut will have full engagement, which seems to be the big issue, that and being able to lock it off properly.

By all means give it a go, as developing/designing these kind of things is a great way to learn.
Let us know how you get on (via pm if you prefer) as i may be able to help here and there, i can probably offer you a prototype kit soon for testing if you don't get anywhere.

Post Tue Sep 18, 2012 5:11 pm

Thanks for the offer of help screech, not got access to CAD at the moment just going to doing things the old skool way (by eye & trial & error) heath robinson stylee.

as for the prototype kit, well if I had the funds i'd have one off you but you know what it's like lol.

if I do get stuck (fingers crossed I don't) i'll be in touch.