MMC brakes on a Caterham

[Unclefester]

Has anyone fitted the early Elise MMC ceramic/aluminium brakes on a Caterham?

 

I think the PCD is Ford, so should be the same as my SV, at least. They are such lovely lightweight units and would reduce unsprung mass quite a bit, at least a kg per wheel.

 

I just happen to have a set here.....

[Paul Richards]

I stand to be corrected, but I wouldn't have thought they would fit. Caterham stub axles (upon which calipers and hubs fit) are similar dimensions to Triumph Spitfire/Herald.

Ford PCD Are you talking about the wheel studs? This is relevant to the fitting of wheels and irrelevant to the fitting of brakes.

 

 

[Shad]

Wrong offset I'd have thought?

[rj]

Elise S1 is different than Ford. Had to have the boss for my wheel balancing machine machined...

[Mankee]

I was speaking to a mate last night who is a development engineer at Lotus about these actually. Most of it went over my head, but he said that the earliest S1 Elises with MMC brakes are hard to find parts for. Most owners swap to normal discs and pads when they get the car and keep the MMC bits for when they sell up. MMCs aren't as good as normal brakes, plus they don't like water much.

 

I think that summarises what he said anyway. I was too busy looking at the finer details of a 5-year-old 60-plate development mule he was using with some trick, hush-hush stuff slapped on it...

[elie boone]

If you want to reduce mass you could go for the HI-Spec 2 pot caliper. It only weighs 800gr and is a direct replacement. Another + is that it uses Elise pads witch are a bit bigger in swept area than the Spitfire ones.

 

BTW the Spitfire caliper weighs about 3 kg.

[Unclefester]

Interesting. That's a good tip about the two pot calipes, thanks, Elie.

I may or may not actually need a bit more braking grunt, with 100bhp more than the car started with.

 

MMC discs not as good as steel? I wonder if the guy had ever actually tried them....they are much better on the Elise than the later steel/cast discs. They give better braking, better suspension performance so better roadholding, produce no brake dust as they don't work by abrasion like normal brakes, but adhesion, and last indefinitely.

 

The ones I picked up recently have done 60,000 miles or so and are unworn. How many iron discs would have been used in that time?

 

They change hands for £600 a set these days! I bought a set recently to retrofit to a 1999 Elise I'm restoring, but I may well swap them onto our S1 111S in place of its drilled & channelled discs and Pagids, which I'd keep for trackdays.

 

The only negative aspects are that if they are wet, there is a slight delay before you get proper retardation, so it pays to be aware of this if driving through standing water or a deluge, but a dab on the pedal prepares them for instant braking easily enough.

 

It's reckoned that for proper circuit use they can be overwhelmed though, but most people agree that for road use they are the best.

 

I thought the offset might not work, but I didn't realise the SV hubs were still Spitfire based.

 

 

Edited by - Unclefester on 11 Feb 2012 10:25:05

[Unclefester]

I think it'd be interesting to try Elise uprights and hubs on the Caterham so the MMC brakes could be used. I don't know what the Caterham discs weigh, but the Elise standard EBC ventilated disc is 5.605kg, while the MMC is 2.9kg.

 

If the twinpot lightweight calipers are used, another 2.2kg is saved. With the alloy Elise uprights, I'd guess another weight reduction over the steel Caterham upright?

 

Does anyone know the weight of the steel uprights, hubs and discs for the SV?

[Unclefester]

In fact, MMC disc pcd IS the same as Spitfire. Not that it's important as I'd want to use the lighter Elise alloy uprights and hubs anyway.

 

The Elise uses two balljoints while the Caterham system uses a trackrod end as the upper wishbone to upright link, and a Rose-joint as the bottom one.

 

I imagine it wouldn't be beyond the wit of man to graft new plinths onto the Caterham arms....

 

Edited by - Unclefester on 11 Feb 2012 19:41:49

[Unclefester]

Quoting Paul Richards: 

I stand to be corrected, but I wouldn't have thought they would fit. Caterham stub axles (upon which calipers and hubs fit) are similar dimensions to Triumph Spitfire/Herald.

Ford PCD Are you talking about the wheel studs? This is relevant to the fitting of wheels and irrelevant to the fitting of brakes.

 

 

Paul, the discs need to have the same pcd as the hubs....and in fact Elise S1 pcd IS the same as Spitfire @ 3 3/4"

 

Obviously the placement of the caliper relative to the disc and the offset of the disc relative to the fitting face would need to be compatible, and certainly new brackets for the calipers would need to be made up, but this is standard procedure in building racing cars!

 

It seems the upgraded Caterham calipers which weigh 800gm, use Elise pads anyway.

 

I'd be surprised if no-one has done this modification before, given the Chapman ethic of lightness and the close relationship/DNA between the Seven and the Elise....which was built as "The Seven for the 1990s"