19 replies to this topic

[Bill USN-1]

I have been searching and have read a lot on the Fiesta MK1 and Mk2 brakes but it seems that most of the discussions are to go from the later 12" wheels/8.4 disc to the 10" wheel 7.9 disc for the "retro" look.


Well I have an Inno(pre 77 Mini) that came with drums. I bolted on a set of 7.5 disc.
I'm looking to improve these 7.5 disc without removing and replacing with 8.4's turrned down to 7.9 and a set of MK2 Fiesta calipers and brackets with turbo hubs.
This won't won't leave much of the 7.5 brakes!!!

Are there any cheap(breaker/junkyard) caliper conversions similar to the fiesta conversion that makes a noticable improvement.

I know there are the metro 4 pot but have read that they really don't make much difference.
Not really interested in the alloy 4 pot($$).

If nothing for calipers then what about the pressure side?
Any benefit to converting to the dual upright master cylinder($$) or the adding of the servo or both?

Thanks

Edited by Bill USN-1, 23 March 2007 - 06:26 AM.

[taffy1967]

Well I've heard that the Fiesta callipers aren't really that good? Something to do with floating pistons?

Anyway fitting a servo will only make the brake pedal feel softer and not really have any effect on brake performance as such.

[The Matt]

deleted because I rambled O/T a little lot!

Edited by mini mad me, 23 March 2007 - 07:27 AM.

[Gr4h4m]

Deleted

Edited by Gr4h4m, 23 March 2007 - 12:18 AM.

[Bill USN-1]

Hey guys....


There are a lot of 7.9 fiesta brake threads...That's why I started this one for 7.5 cooper brakes!!!!!

Can we stay on topic for those that use the search button in the future.

Thanks.

I'm still looking for improvements to the factory 7.5 disc brakes.

[Gr4h4m]

Hey guys....


There are a lot of 7.9 fiesta brake threads...That's why I started this one for 7.5 cooper brakes!!!!!

Can we stay on topic for those that use the search button in the future.

Thanks.

I'm still looking for improvements to the factory 7.5 disc brakes.

Not sure I understood your first post.Good luck with your quest

[Bill USN-1]

Thanks,
I edited the original post so hopefully there won't be any confusion. Sorry if it was unclear.

One specific question...
Will swapping from this MC...



To this MC and pipe kit, make any difference in braking with the 7.5's?


and this



or is one of these a viable option either seperate or with the above.

Edited by Bill USN-1, 23 March 2007 - 06:48 AM.

[The Matt]

Sorry to go O/T, I think I misunderstood your first question. I thought you were asking the pros and cons of caliper conversions from salvage yards, which is why I harped on about the Fiesta conversion.

In response to your question abuot upping the pressure in the system by using a different master cylinder, ummm:

All I know is that by upping the pressure in the same system, you will obviously have more clamping force (as obviously force = pressure x area). As I can't see the piccies in the thread (for some reason) I don't know which components you are on about swapping.

I don't know if a higher pressure O/E system existed for the Mini, but if it does, you could go for a larger MC with a servo (to reduce pedal effort)...... I guess?????........ but I'm just rambling now to try and make up for my first off topic post!

I know there were different bores of wheel cylinder, but I really don't know about the master cylinder side of things I'm afraid!

[Stoo]

You are unlikely to increase the clamping force by changing master cylinder or slaves. You will change the effort/clamping ratio but equally you will change pedal travel too (which is bad if you toe n' heel). Ignoring fade for a minute, most gain comes from 1) increasing the size (diameter) of disk which you are not keen on 2) increasing the pad area which unless you change the caliper you can't do either. This leaves the pad compound which is something you **CAN** do something about. Have you tried upgrading the pads yet and if so which have you tried?

Contrary to popular viewpoints I actually find the new greenstuff compound to be quite good. Better was Mintex 1144 but that really only suits spirited driving as they're much better hot. When cold you'll find you have to press harder than you normally do now.

What do you want from your brakes?

[Bill USN-1]

Sorry to go O/T, I think I misunderstood your first question. I thought you were asking the pros and cons of caliper conversions from salvage yards, which is why I harped on about the Fiesta conversion.

If you refer to using the fiesta caliper with the 7.5 disc then it's on topic.
But I have not read any threads where it was actually done. Seemed to be a lot of worry with the amount of grinding to clear the hub.

If it can be performed by just bolting on a set of 7.9 rotors during a brake job then it may be a viable option in the future if I need to replace the rotors.

But it sounded like the upgrade to Fiesta calipers was an all or nothing conversion which means all the 7.5 brakes would be removed and replaced!!! Not a very economical upgrade. Relitively speaking.....

So I was asking if there were any other caliper swaps using parts from the breakers that will increase the contact area.

I just figured that as long as the mini has been raced that someone/many have already come up with simple parts upgrades. I thought the metro 4 pot would be an option but the more i read the less it seems to be a real improvement.

Maybe the design of the mini hubs and rotors limits the options out there. Along with the 10" wheel space.

So far i have only installed the 7.5's and found them fair in braking. quite a bit of pressure required. But better then the drums.

I just recieved my SS lines and new pads but will have to get the number off of them to be sure what I ordered.


Thanks for the inputs so far. I appreciate any and all.
I'm just trying to concentrate on getting the most out of the 7.5's.
Maybe I'm asking too much from them.

[Dan]

The problem is that the disc position relative to the hub centreline is different on the two setups, Cooper S and 8.4" (and different again on the 7" Cooper setup but the less said about that the better). So you can't just swap the caliper from one setup onto the disc from another. The only way you can improve the caliper on the 7.5" setup is to use an alloy 4 pot. Metro 4 pots don't fit as the disc is in the wrong place for them. You can improve the pedal effort with a servo or play with the brake distribution by changing the master or slave cylinders or fitting a proprtioning valve or change the pad material but that's about it for options if you keep the Cooper S drive flanges. It's the drive flange that is the important part here. Personally I far prefer the Cooper S flange because I think it holds the disc and wheel to the drive shaft far better than the late type does. As for pad material, it's funny reading what Stoo says above because I have always found the opposite! I had Greenstuff pads for years (I wouldn't exaclty call it a new compound!) but found that these really do need to be quite warm for use whereas the Mintex seems to stay relatively stable whatever temperature it is.

[Guess-Works.com]

IMO, if you want to stick with 7.5's then the ONLY choice is a set of alloy 4 pot calipers... it has the advantage of being a straight swap for your std cooper calipers, and the increase in pad area provided ( they use Metro pads ) realy does make a difference...

I personally rate that setup over the std 8.4" setup.

As with Dan, I use Mintext pads, and have never suffered any ill effects with them, they have good life expectancy and there's no 'warming' up needed..

[Gr4h4m]

You are unlikely to increase the clamping force by changing master cylinder or slaves. You will change the effort/clamping ratio but equally you will change pedal travel too (which is bad if you toe n' heel). Ignoring fade for a minute, most gain comes from 1) increasing the size (diameter) of disk which you are not keen on 2) increasing the pad area which unless you change the caliper you can't do either. This leaves the pad compound which is something you **CAN** do something about. Have you tried upgrading the pads yet and if so which have you tried?

Contrary to popular viewpoints I actually find the new greenstuff compound to be quite good. Better was Mintex 1144 but that really only suits spirited driving as they're much better hot. When cold you'll find you have to press harder than you normally do now.

What do you want from your brakes?

I agree with the above.

[Dog]

As with Dan, I use Mintext pads, and have never suffered any ill effects with them, they have good life expectancy and there's no 'warming' up needed..

Also the proper unipart pads are just as good, but alot cheaper
You do need to remember that only a certain number of wheels will allow 4pots under the rim...

[Guess-Works.com]

Had, Dunlop D1's, Reverse Rims and Superslots over mine, think the only one which has any difficulty are Mamba's....