Small aftermarket calipers for 15 inch wheels?

[Rutschpartie]

Mk8 single piston brake calipers are already very tight with 15 inch wheels, does anybody know if 4 piston aftermarket calipers (maybe alcon) with 15 inch wheels work, and if they are a real improvement?

 

[M-Sport fan]

The M-Sport Poland R2/R2T gravel spec Alcons will work under almost all 15" wheels, since that is the size wheel which they are forced to use on gravel rallies.

But yeah $$$$$ as compared to all else out there. (I don't have the Euro symbol on my keyboard. LOL)

There is (was??) a rally prep shop in Colorado, USA (O.D.D. Racing) which put together a 4 piston Wilwood kit for 15" rally wheels on the Fiesta ST, specifically due to the exorbitant co$t of that M-Sport kit.

They most definitely would be an improvement, but the bother/expense is most likely not worth it unless you are running around the 'rings (Hungaro and Nurberg), or your local road course at speed.

 

[kevinatfms]

Mk8 single piston brake calipers are already very tight with 15 inch wheels, does anybody know if 4 piston aftermarket calipers (maybe alcon) with 15 inch wheels work, and if they are a real improvement?

The calipers really aren't the issue with the Fiesta ST. The rotor size in diameter, thickness and overall thermal capacity is the issue. The M-Sport setup stated above uses a MUCH thicker rotor setup to achieve the same as running a larger rotor. Remember, the brake rotor is a massive heat sink. The more heat it can absorb and bleed off the better. Stock rotor diameter for a Mk7 is 24mm(IIRC) and most aftermarket setups start at 26mm and up. I assume the M-Sport kit probably went with 26-28mm thick rotors knowing the 15" diameter wheel limit. Anyone have any information on the M-Sport kit?

Also, most rally cars also have enough ducting to blow more air than Hurricane Ian. Most Fiesta's run 2.5" ducting from the lower air dam or bumper fog light holes at best.

 

[Rutschpartie]

The calipers really aren't the issue with the Fiesta ST. The rotor size in diameter, thickness and overall thermal capacity is the issue. The M-Sport setup stated above uses a MUCH thicker rotor setup to achieve the same as running a larger rotor. Remember, the brake rotor is a massive heat sink. The more heat it can absorb and bleed off the better. Stock rotor diameter for a Mk7 is 24mm(IIRC) and most aftermarket setups start at 26mm and up. I assume the M-Sport kit probably went with 26-28mm thick rotors knowing the 15" diameter wheel limit. Anyone have any information on the M-Sport kit?

Also, most rally cars also have enough ducting to blow more air than Hurricane Ian. Most Fiesta's run 2.5" ducting from the lower air dam or bumper fog light holes at best.

On smaller rallyX tracks I visit once a month temps are ok with stock ST sized discs + calipers and ferodo DS2500 pads + better fluid!
You are right: for fun i did trackdays on F1 circuit Spielberg and also Salzburgring here in Austria last year and yes, brakes were completely destroyed after the day (fading, warped rotors, cooked pads and fluid).

But my question is: would there be a big improvement in actual braking distance with increased piston count on a small caliper (ofc on ashpalt with tires that can provide the grip). I only now guys with bigger kits, that made a big difference.

 

[Rutschpartie]

The M-Sport Poland R2/R2T gravel spec Alcons will work under almost all 15" wheels, since that is the size wheel which they are forced to use on gravel rallies.

But yeah $$$$$ as compared to all else out there. (I don't have the Euro symbol on my keyboard. LOL)

There is (was??) a rally prep shop in Colorado, USA (O.D.D. Racing) which put together a 4 piston Wilwood kit for 15" rally wheels on the Fiesta ST, specifically due to the exorbitant co$t of that M-Sport kit.

They most definitely would be an improvement, but the bother/expense is most likely not worth it unless you are running around the 'rings (Hungaro and Nurberg), or your local road course at speed.

thx! will try to find out what calipers they used or if they still sell them, depending on the price it could be worth a try. I know some guy who should be able to make custom brackets.

 

[kevinatfms]

On smaller rallyX tracks I visit once a month temps are ok with stock ST sized discs + calipers and ferodo DS2500 pads + better fluid!
You are right: for fun i did trackdays on F1 circuit Spielberg and also Salzburgring here in Austria last year and yes, brakes were completely destroyed after the day (fading, warped rotors, cooked pads and fluid).

But my question is: would there be a big improvement in actual braking distance with increased piston count on a small caliper (ofc on ashpalt with tires that can provide the grip). I only now guys with bigger kits, that made a big difference.

The pads overheating means you are using the wrong pads. Higher temp threshold pads, better fluid and ducting is absolutely required on this car at a MINIMUM.

I run Porterfield R4's, ducting, lines and RBF600 and have only gotten fade at the end of one day so far. I also contribute that to some old fluid the last time i went out. Will see if RBF600 fluid was all that was needed.

On smaller rallyX tracks I visit once a month temps are ok with stock ST sized discs + calipers and ferodo DS2500 pads + better fluid!
You are right: for fun i did trackdays on F1 circuit Spielberg and also Salzburgring here in Austria last year and yes, brakes were completely destroyed after the day (fading, warped rotors, cooked pads and fluid).

But my question is: would there be a big improvement in actual braking distance with increased piston count on a small caliper (ofc on ashpalt with tires that can provide the grip). I only now guys with bigger kits, that made a big difference.

If the pad is larger then yes. If the pad is the same size i believe it comes down to just allowing more even pressure to the pad backing plate versus a single piston sliding caliper to eliminate uneven pad wear.

 

[kevinatfms]

thx! will try to find out what calipers they used or if they still sell them, depending on the price it could be worth a try. I know some guy who should be able to make custom brackets.

That kit is most likely the TCE 11.75" kit that i have been quoted recently at $1600 + shipping. Uses a Wilwood GT rotor in 11.75 diameter x.810 thickness. 4 piston DPS calipers. TCE brackets, lines and hardware.

 

[M-Sport fan]

That kit is most likely the TCE 11.75" kit that i have been quoted recently at $1600 + shipping. Uses a Wilwood GT rotor in 11.75 diameter x.810 thickness. 4 piston DPS calipers. TCE brackets, lines and hardware.

That sounds about right, since O.D.D. Racing quoted me ~$1500 before shipping, about 3 or so years ago.
The M-Sport kit is most likely more than twice that price currently.

 

[Rutschpartie]

Thx for your help! With the price for all the hardware needed in relation to the small increase in pad size I am not rly convinced to do this upgrade, even if clearance would be fine with 15 inch. My rotors and ferodo pads could always handle my current sessions on small tracks in the past - if I only have to change pads and bleed often I am ok with that. My rotors and braided brake lines seem to last forever. I discovered that the Fiesta Rally5 also uses stock ST calipers so I think I am fine.

 

[esp_martin]

Thx for your help! With the price for all the hardware needed in relation to the small increase in pad size I am not rly convinced to do this upgrade, even if clearance would be fine with 15 inch. My rotors and ferodo pads could always handle my current sessions on small tracks in the past - if I only have to change pads and bleed often I am ok with that. My rotors and braided brake lines seem to last forever. I discovered that the Fiesta Rally5 also uses stock ST calipers so I think am fine.

I don't know who makes brake cooling guides for the Mk8 Fiesta but you should also look into something like this:

AIRTEC Motorsport Brake Cooling Guides - Mk7 Ford Fiesta – AET Motorsport

The link is for the AIRTEC Mk7. Boomba has a similar setup in the States for American Fiestas but both work on Mk7/ST180. Not sure if they work on Mk8s though. Either way I've read these cooling guides are a must if you don't want to install ducting on your Fiesta. Getting more convection cooling on the rotors goes a long way toward keeping them from warping.

 

[M-Sport fan]

Thx for your help! With the price for all the hardware needed in relation to the small increase in pad size I am not rly convinced to do this upgrade, even if clearance would be fine with 15 inch. My rotors and ferodo pads could always handle my current sessions on small tracks in the past - if I only have to change pads and bleed often I am ok with that. My rotors and braided brake lines seem to last forever. I discovered that the Fiesta Rally5 also uses stock ST calipers so I think am fine.

Yes, the R1 (now Rally5) cars (basically, showroom stock rallying) use our brake setup, anything above/faster than that class uses the Alcons. AP Racing, or the all-out Brembo setups.

Ironically, even those cars now come with a 5 speed Sadev sequential gearbox, despite scrimping on the brakes.

I wish that we could easily get the Ferodo pads for our cars here in the states.