Any Engineers? (Brake disc bells)

Post Mon Apr 11, 2005 9:50 pm

I need an engineer to make some disc bells for me.

Basically I want the rear disc bell copying in steel (as opposed to the standard cast disc) but I want it drilling to accept an AP vented Motorsport disc. (Similar to these)

This is so I can use the standard mechanical handbrake internally in the bell.

Any help appreciated, good price paid if anyone can do it by copying a new disc, without a drawing.

I'm based near Leeds but location may not matter.

Any other suggestions for using a vented rear disc on an E36 Compact welcome. (Same rear end as E30. Deeper offset disc with Compact, E30 M3 non vented rear fits, but 20mm spacers required each side.)

Post Mon Apr 11, 2005 10:17 pm

Fcuk a duck!

They're HUGE! Especially for the back!

You've probably considered it already, but would it not be possible to machine a solid disc to accept those? That way you could just machine part of the O/D off the disc, turn a shoulder to locate the monsters there and drill the PCD to hold it on?

Just a thought.

Not sure my lathe's really big enough to turn anything that big though, what size and grade material are we looking at just out of interest?

Post Tue Apr 12, 2005 9:04 am

They're HUGE! Especially for the back!

I don't know how big those ones are, it's just a pic I grabbed from ebay to demonstrate the principal. I'm wanting to use approx 300mm discs with Brembo 2 pots.

You've probably considered it already, but would it not be possible to machine a solid disc to accept those? That way you could just machine part of the O/D off the disc, turn a shoulder to locate the monsters there and drill the PCD to hold it on?

That's basically what I'm wanting to do, the standard discs are cast tho' and drilling them etc wouldn't be as good as using a 'turned replica'. (So I'm told?)

I can use Z3M rear arms/hubs/discs but they are 20mm narrower each side and I want to avoid using spacers.

I can just use the Z3M discs on my hubs which would be fine, except the standard mechanical parking brake wouldn't work with this set up. (I'm using a hydraulic handbrake operated by a seperate lever, my car has to be road legal and therefore I have to have a mechanical parking brake too.)

Anyone fitted rear vents on an E30?

Any other suggestions?

Post Tue Apr 12, 2005 9:59 am

Hi, just an idea, you don't have to have a mechanical hand brake for the car to be road legal. You just have to have a mechanical system for locking the brake on. So as long as you hydraulic hand brake has a ratchet built in to it it should be ok.

I know a guy who built a trike and foo the handbrake just put and extra disc on the front and an extra lever with a huydraulic tap. He just squezed the lever to lock the brake then turned the tap to the off position, passed the sva and mot.

Post Tue Apr 12, 2005 10:04 am

Hi, just an idea, you don't have to have a mechanical hand brake for the car to be road legal. You just have to have a mechanical system for locking the brake on. So as long as you hydraulic hand brake has a ratchet built in to it it should be ok.

I know a guy who built a trike and foo the handbrake just put and extra disc on the front and an extra lever with a huydraulic tap. He just squezed the lever to lock the brake then turned the tap to the off position, passed the sva and mot.

Ta for that. My hydraulic lever does have a mechanical lock.

I've always been told that it has to have an actual mechanically operated brake, can anyone cofirm this either way for sure?

Post Tue Apr 12, 2005 10:12 am

My sxperience is totally from the SVA with building kit cars. ANd I can tell you that from the sva manual I have you can use a mechanically locked hydraulic hand brake.

Also I had a mate who put a lock valve in the brake pipes to the rear of his mini, mot man let that through.

Post Tue Apr 12, 2005 10:24 am

Thanks Widge.

I'll speak to the MOT station where it'll be tested.

Post Tue Apr 12, 2005 10:56 am

Speak/contact a guy call Ian Godney at the following website - He has an handbuilt M3 Rally Car and what he doesnt know about brakes........well anything in that area!

http://www.godspeedbrakes.co.uk/

He can machine whatever you are looking for with bells, spacers, caliper brackets....

Post Tue Apr 12, 2005 11:05 am

Nostrils wrote:Speak/contact a guy call Ian Godney at the following website - He has an handbuilt M3 Rally Car and what he doesnt know about brakes........well anything in that area!

http://www.godspeedbrakes.co.uk/

He can machine whatever you are looking for with bells, spacers, caliper brackets....

I've contacted Ian already, I don't think 'one offs' are his thing.

I've also spoken to the MOT station who wont pass it without a driver operated mechanical brake, he says it has to be a mechanical linkage all the way from the driver to the brake, which until recently had to work directly on the wheel hub. (Unacceptable being in board)

I'm confused now.

Post Tue Apr 12, 2005 11:17 am

That's absolute bo**cks he's just benig arsey. Try another MOT station. How the system works is irrelevant as long as it satisfies the MOT criteria, ie. sufficent brake force and can't be knocked off by accident etc

Post Tue Apr 12, 2005 11:39 am

Widge wrote:That's absolute bo**cks he's just benig arsey. Try another MOT station. How the system works is irrelevant as long as it satisfies the MOT criteria, ie. sufficent brake force and can't be knocked off by accident etc

He gave me a lecture about wagon brakes being held on by a spring and air pressure releasing them, as opposed to air pressure applying them which is what most people assume.

Any links to official info'?

I can't find any.

It would make life a lot easier for me if I could ditch the standard handbrake lever, apart from being able to use the Z3M discs, the hydraulic lever is annoyingly close to my left knee and could be relocated to the standard handbrake position.

Post Tue Apr 12, 2005 11:45 am

OK try finding another MOT station and just don't tell them :lol:

Post Tue Apr 12, 2005 6:46 pm

A seperate MOT station told me that a mechanical brake is required.

So, back to original question.

Post Tue Apr 12, 2005 6:53 pm

M3Compact wrote:He gave me a lecture about wagon brakes being held on by a spring and air pressure releasing them, as opposed to air pressure applying them which is what most people assume.

This is just so that they are 'fail-safe' is it not, and it's not relavant.

Nor is this post

Post Tue Apr 12, 2005 7:00 pm

This is just so that they are 'fail-safe' is it not, and it's not relavant.

It was to demonstrate that wagons have a mechanical brake in case of system failure. (IE if the braking system fails on a wagon by the compressor failing, the brakes would be locked on as opposed to inoperative)

Nobody fitted rear vents on an E30?

Post Tue Apr 12, 2005 7:20 pm

someone did the i.x vents and wide caliper convert, cant remember who but i think it was demlot

dont think it compares to what u have in mind though

Post Tue Apr 12, 2005 8:03 pm

johnono wrote:someone did the i.x vents and wide caliper convert, cant remember who but i think it was demlot

dont think it compares to what u have in mind though

The Z3M conversion must be easy for E30s, I need 40mm extra track tho'. I suppose it's finding big enough fronts which is the problem for E30s.

Not sure my lathe's really big enough to turn anything that big though, what size and grade material are we looking at just out of interest?

The size would be approx 200mm Dia 150mm deep, I can't see a particularly high grade steel being necessary.

No engineers fancy cloning a rear disc to use as a bell?