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Quantum (Mk2 Fiesta) brake options?
Nickp - 19/12/18 at 05:38 AM

Now I've got the Quantum going well I need to look at the front brakes before using all that new found performance.
It currently has very small 221x10mm solid front discs. They actually feel OK in normal use in this light (800kg) car with a servo and already have Mintex M1144 pads on new discs, but I know they will fade when used in anger.

The simple bolt on solution would be to upgrade to XR2 240mm vented discs but these seem to be hard to find these days

Another option apparently is 4x4 Cossie calipers on a Mk5 Escort 260mm vented disc. Which sounds ideal to me but again the calipers/carriers are becoming rarer and the cost goes up if you can find them.

I think I can possibly use 253mm solid Sierra rear discs by just making a simple bracket to move the existing calipers out by the required amount. A cheap and simple solution, but are they going to be up to the job? This doesn't sound like a big increase (32mm) but previously I put 30mm bigger discs on my old Lancia Montecarlo and that made a huge difference.

I've also got a pair of 283mm vented Cossie discs that I was going to use with Mondeo calipers but they are more of a challenge to fit and tbh I think they'll be overkill in such a light car, even on track.

I'm tempted to try the solid Sierra rears for now just for simplicity / cost.

Any thoughts / experience?

Thanks in advance,
Nick


cliftyhanger - 19/12/18 at 07:53 AM

I would go vented if you are concerned with fade, as they dissipate heat so much faster.
My spitfire (about same weight) is running an ST170 engine circa 175-185BHP. I am using 240mm Capri vented discs and M16 callipers at the front. No signs of fade either on the current DS2500 pads, or even OEM asbestos pads (which have similar characteristics to 1144's). It has done a few track days and plenty of alpine passes where others have cooked their brakes.


Nickp - 19/12/18 at 10:19 AM

quote:
Originally posted by cliftyhanger
I would go vented if you are concerned with fade, as they dissipate heat so much faster.
My spitfire (about same weight) is running an ST170 engine circa 175-185BHP. I am using 240mm Capri vented discs and M16 callipers at the front. No signs of fade either on the current DS2500 pads, or even OEM asbestos pads (which have similar characteristics to 1144's). It has done a few track days and plenty of alpine passes where others have cooked their brakes.


Thanks. Yes ideally I would prefer vented for the reason you state, heat dissipation. But that puts me back to trying to find either XR2 or 4x4 Cossie calipers / carriers. I think 240-260mm is the sweet spot for disc size on our cars it's just finding the best way to achieve this without spending too much money.


cliftyhanger - 19/12/18 at 10:23 AM

There are brand new mk5 escort calipers on ebay pretty cheap... suit 240mm disc. Would a mk5 escort disc fit? (they are not the bigger calipers, which I think are 260mm disc size as fitted to the "fast" versions)
If you want cheap:
https://www.ebay.co.uk/itm/FORD-ESCORT-MK5-MK6-PAIR-FRONT-BRAKE-DISCS/123412799646?fits=Model%3AEscort%7CPlat_Gen%3AMK+V&hash=item1cbbf9e09e:g:HBA AAOSw989bu1Y3:rk:1:pf:0
and add
https://www.ebay.co.uk/itm/NEW-NOT-RE-MANUFACTURED-Pair-of-Ford-Front-Brake-Calipers-Escort-Mk-5-6-7/233049691262?epid=25005463507&hash=item3642d8 147e:g:X2UAAOSws2RcDRNZ:rk:2:pf:0

about £50 all in if you get lucky!

[Edited on 19/12/18 by cliftyhanger]


Nickp - 19/12/18 at 10:31 AM

quote:
Originally posted by cliftyhanger
There are brand new mk5 escort calipers on ebay pretty cheap... suit 240mm disc. Would a mk5 escort disc fit? (they are not the bigger calipers, which I think are 260mm disc size as fitted to the "fast" versions)


Cheers but I don't think the MK5 calipers fit, just the discs. It's only the XR2 and 4x4 Cossie carriers that are a straight bolt on from what I can gather from the limited info online.


cliftyhanger - 19/12/18 at 11:29 AM

Ah, nothing like a simple solution!


jps - 19/12/18 at 03:26 PM

Aren't the non-Cosworth Sierra calipers appropriate at all? RWD Sierras came in 240 and 260mm vented (and 240 unvented).


Nickp - 19/12/18 at 07:05 PM

quote:
Originally posted by jps
Aren't the non-Cosworth Sierra calipers appropriate at all? RWD Sierras came in 240 and 260mm vented (and 240 unvented).


The discs certainly aren't as they are too deep and hit the bottom ball joint. I've got a set of front carriers sat next to it on my Haynes so may offer one up at the weekend and see if it's an option. I also have some Sierra rear discs on the same car I can try with the OE calipers