M Roadster brakes on E30 with M3 running gear possible?

[jaistanley]

I have just got a crashed damaged M roadster to break for parts to fit to my 318is with M3 running gear..

I was lucky enough to bid for the engine on ebay and offered 400 quid more for the rest of the car which they accepted.. Cool eh?

The rear trailing arms are damaged beyod repair but the brakes on them seem good. The front struts are fine and as such the brakes are OK..

Will these fit to my M3 struts and will the rears fit to my M3 trailing arms? The problems I can imagine with the fronts will be incorrect disk offset, incorrect spacing between caliper bolts and or incorrect offset of caliper. The rears look a little more promising but I just don't know as of yet. Unfortunately I'll need to fit some sort of 17"'s which personally I dont think will suit my car (std looking 318is) but Ho hum big brakes are a must!

Anyone done this or know if it's possible?

Many thanks..

Jai

[Kos]

complete rear axel will fit with diff, a compact diff will fit and use any e30 diff (M roadster/coupe have different bolt paterns for the drive shafts)

front legs will also fit, but you may need to change your wishbones, not too sure, DEMLOTis the man to ask

but its all possible and not too bad a conversion

[jpboost]

There's a guy over on one of the american m3 forums (s14.net) who fitted z3 front struts to his m3. I can't remember all the thread details, but I think it was seen to be not quite ideal.
Have a search for his threads on there (his username is GMW-CSL ) his car had plenty of mods including an LS1 vette engine.

[jaistanley]

The rear beam is smashed to oblivion.

Both rear swingarms are bent and one has ripped out of its mounting points and off the car shearing the damper rod.. Not pretty. I need to know if the caliper/caliper lugs/disks/handbrake/splashguard from the roadster fit the M3 rear swingarms..

I don't really want to fit the front struts.. The method of fitting e36/compact struts (using offset bushes and evo wishbones to counteract incorrect geometry) strikes me as a compromise over the M3 stuff I have at the moment. I may be wrong, I haven't measured anything yet, but I think the M3 stuff designed for the E30 chassis is the safer bet. Plus I have it so can sell the roadster struts to a Z3 or Compact driver (or maybe one of you guys looking for 5 stud conversion?)!

My question is can I fit the brakes from the roadster?..

Many thanks though.

Jai

[Kos]

too much agro, the only time i've seen it is when the complete front leg has been fitted,

you will need to fabrecate caliper mounts and a suitable disk

but anything is possible

[jaistanley]

Not just a bolt on job?

Shame. Perhaps I'll sell the whole front struts as one. Will be worth more anyway. Can put the money toward a set of big brakes that'll fit under 16"'s then and get the M3 BBS 16"'s.

With a nice set of low profile 4 pot calipers I may be able to get the same size disks under 16's instead of 17's anyway.

Will the rears fit and if so, will they fit under 16's? I can try it out but asking here helps me sort out a budget for the next few months without getting oily, cold or sacked for not turning up!

Many thanks for all replies.

Jai

PS Definately wont bolt on....?? Pretty please, tell me they will!

Lame.

[Kos]

wont bolt on

you gan get 4pots under a set of 15" rims on the M3, khumo racers do but they mostly run compomotive rims to help clearance bu they still use big disks aswell

that you best bet
godspeedbrakes.co.uk could help you out

[Demlotcrew]

Thanks for getting back to me.

Andrew

[Jordan]

I have complete M-Roadster rear trailing arms/brakes on my e30. Wonderful

You won't be able to run just the brakes though no sorry. The entire trailing arm/brakes as a unit will bolt directly in place of the stock trailing arm/brakes though.

[Kos]

Thanks for getting back to me.

Andrew

[Jordan]

The front M-Roadster strut assemblies, rotors, and calipers are the same as e36 M3.

You CAN fit the e36 M3 front rotor and caliper to your e30 M3 or e30 M3 strut housing equiped e30.

You will need a rotor spacer from SBI
http://www.sbibmw.com/site/main.htm



It fits between the hub and rotor, and the e36 M3 caliper bolts right on. I also run this setup on my car.

[jaistanley]

Demlotcrew: Andrew...

Sorry I didn't PM you back. Had a similar email from pete and replied to that but didn't get back to the zone.. Was using the internet at work and between bidding for car, organising my mate phill to help me pick it up and getting my mum to lend/send me the cheque (mummys boy) It went out of my head..

I've PM'd you now...

Hope all is forgiven..

Jordan: Thanks for the info.. Were those spacer expensive? What diameter, thickness and offset are the disks if you know? I ask so I can see if I can find any disks of similar spec (ally bells and separate rotors for example) I can use instead..

What size wheels/tyres do you use to run these brakes? They look large! Do they rub at all and whats the ride like? Did they adversely affect your handling?

Many thanks guys...

Jai

[Jordan]

I run stock e36 M3 wheels. M System DoubleSpoke II's

17x7.5 front 225/45R17
17x8.5 rear 245/40R17

I'll be running 17x8.5's in the front too soon, with 245/40R17 as well.

No clearance or rubbing problems.

I won't disclose the specs on the rotor spacer, if you want want you'll need to buy one. They are $190USD a pair or so.

The stock e36 M3 front rotor is 315x28mm.

I have very stiff coilovers, and Koni SA's. 17in wheels are the least offensive item in the rough ride department.

[jaistanley]

I'm not looking for the specs of the spacer.. I'd like to know the offset fron the hub face to the outer disk braking surface or centre line of the disk. I'm certainly not going to start producing rip off's of their product !?!

I was asking so I knew the offset of the calipers so I can spec some different disks, from another manufacturer.

Does anyone know of a website with disks dimensions on? I'm going to measure it all up etc it's just be nice to be able to choose from a list etc.

Thinking about getting some floating rotors and alluminium bells to fit the calipers to my hubs. Wilwood do some cheap ones at rally design.co.uk

Good idea?

Many thanks..

Jai Stanley

[Demlotcrew]

The better upgarde is to use the E46 M3 disks as they are ally in the centre thus making them lighter and you can then use the 4 pot clipers on them. (they are also larger, 315 E36, 325 E46)

If you need the spacers i know someone who is about to make a few (Around Ԛ£110 for the fronts)

Andrew

[Turbo-Brown]

Jai, just out of interest:

If the rear beam's been smashed to bits, is the gearbox OK?

Would've thought the prop might have transmitted a whach to it that's all

[jaistanley]

Hmmmm, that does sound pretty good.

I'm going to nee to do something good with the ammount of power it'll be pushing..

Ԛ£110 is a good price for something that'll mean I can bolt 315mm brakes straight on, trouble is I'll need to fit 17" wheels. It also means I can fit the E46 brakes from the M3 then yea? Not an option as they'd cost money (unless the disks fit under the M roadster calipers which I very much doubt, 10mm bigger).

Getting hold of some 5 series/7 series brakes may be another answer.. Look at this page: http://member.rivernet.com.au/btaylor/B ... E28M5.html

It has loads of upgrades suitable for the E28. I have M3 front struts so the front will fit. Will the rears mentioned on this same page? IE are e30 M3 rear brakes interchangeable with the mentioned cars?

I'm yet to get the car stripped. If the gearbox is shafted I'm in for an expensive repair. Just seen one go on ebay too.. I really hope its all OK.

I'll have to wait until the weather turns from baltic to just cold..

Jai