11" Brake Rotor

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DPDISXR4Ti
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Re: 11" Brake Rotor

Post by DPDISXR4Ti »

brokencase wrote: Sun Jul 05, 2020 4:42 pm I'm back to the question of "Is the stock Scorpio braking really so bad?"

Re-drilling rotors? It's just not worth the trouble...effort better spent elsewhere.. Your talking about a rotor size change 9.95 to 10.7?
How much does that get you? An extra 3/8" around the perimeter?

It's not a question of availability...plenty of stock rotor choices up on rockauto..
No, the factory Scorpio braking isn't that bad. In fact, it's better than the factory XR braking due to the Teves electric booster (even without ABS). For me, a big factor is a readily available supply and selection of parts. I'm quite sure I'll find brake pads and calipers for a 2016 Ford Focus a lot more readily than a 1988 Scorpio. That would have been a big plus for me in 2008 when I had a stock caliper seize up while at Carlisle. No XR4Ti calipers to be found at the local Autozone or Advance that day, but I bet today I'd find them on the shelf for a 2016 Focus.

Availability of after-market parts is also a plus when using parts from commonly available vehicles. I'm sure I could find all sorts of flex lines, pads, and rotors for a 2016 Focus.

Re-drilling the rotors is annoying, and I realize not everyone has a drill press. Fortunately, it's not an uber-precise requirement when drilling rotors as it is for re-drilling a hub. People have done it with a hand drill.
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Re: 11" Brake Rotor

Post by brokencase »

But if for some reason you needed a new rotor while you are out on the road then you will have to go find a drill press!
Carrying spare pre-drilled Focus rotors around with you is just as crazy as carrying around spare Scorpio calipers.

Caliper seizures are really rare. It is a failure mode so far down on the Scorpio list of things to worry about... Yes I understand you have experienced this, but it doesn't justify the extent of such a conversion.

Plenty of stock Scorpio rotors & calipers up on RockAuto and tons of "Drilled rotor/ Carbon Pad" upgrade kits up on ebay. And they are cheap, not too many buyers for these out there! It is a boon to Scorpio owners.

How about this...carry a caliper rebuild kit with you in the car? $3?
I converted my Bugeye Sprite to disc brakes. Those calipers I think came from a 1967 Midget. That makes them 53 years old. New caliper rebuild kit and converted to silicone brake fluid. I think they will now last another 100 years.

Does anybody know if the Scorpio ABS would work with silicone brake fluid? THAT would be interesting...It would be worth while even if there was a slight decrease in braking performance.

In any case, The Focus conversion might be useful for that day when correct parts are no longer available. As it stands now, I can't see that happening for another 20 years...
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Re: 11" Brake Rotor

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brokencase wrote: Thu Jul 09, 2020 9:14 am But if for some reason you needed a new rotor while you are out on the road then you will have to go find a drill press!
The risk of a catastrophic rotor failure requiring emergency field replacement seems near zero to me. Caliper seizure on the other hand is not terribly unusual. I've experienced it myself at least 3 different times, the most notable being the aforementioned incident at Carlisle 2008.

Your points for wanting to stay stock are valid and I have no issue with you staying mired in 80's technology. :mrgreen:
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Re: 11" Brake Rotor

Post by Ed Lijewski »

Three different times, each with PBR not Scorpio calipers.

(BTW, the technology is the same; the product numbers are different.)

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Re: 11" Brake Rotor

Post by DPDISXR4Ti »

Ed Lijewski wrote: Thu Jul 09, 2020 1:47 pm Three different times, each with PBR not Scorpio calipers.
Nope. Only once with a PBR. The one that seized up on Rt. 581 in 2008 was a stock XR caliper.
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Re: 11" Brake Rotor

Post by brokencase »

DPDISXR4Ti wrote: Thu Jul 09, 2020 10:06 am
Your points for wanting to stay stock are valid and I have no issue with you staying mired in 80's technology. :mrgreen:
80's technology? What's changed?

I think I'll put a set of these on and call it a day...
https://www.porterfield-brakes.com/Prod ... d%20Brakes
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Re: 11" Brake Rotor

Post by John Brennan »

brokencase wrote: Thu Jul 09, 2020 5:06 pm
DPDISXR4Ti wrote: Thu Jul 09, 2020 10:06 am
Your points for wanting to stay stock are valid and I have no issue with you staying mired in 80's technology. :mrgreen:
80's technology? What's changed?

I think I'll put a set of these on and call it a day...
https://www.porterfield-brakes.com/Prod ... d%20Brakes
Very much agreed. Scorpio brakes are essentially Sierra Cossie brakes-- those brakes ain't broke and don't need fixin.'
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Re: 11" Brake Rotor

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brokencase wrote: Thu Jul 09, 2020 5:06 pm 80's technology? What's changed?
The big smiley = sarcasm (for the most part)

That said, show me any modern car over 2800 lbs with 10" brakes.
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Re: 11" Brake Rotor

Post by Ed Lijewski »

That likely is driven by the trend to upsized wheels. Gotta fill those increased open spaces.

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Re: 11" Brake Rotor

Post by john keefe »

Nothing as funny to me as seeing a Honda/Toyota dropped, with huge rims, an unpainted body kit and fart-can tailpipes, but with rotors the size of a small dinner plate, and those tiny rear drums.
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Re: 11" Brake Rotor

Post by timxr8 »

Ed Lijewski wrote: Sat Jul 11, 2020 12:49 pm That likely is driven by the trend to upsized wheels. Gotta fill those increased open spaces.

YMMV
I'd argue it's the increase in speed and size of the cars. A modern Focus weighs over 500lbs more than the original. It's ridiculous. We either want to save the planet or we want to have a "bulletproof" car. We can't have both. I'd argue a lighter car that can avoid accidents is far better, but then you gotta compete with people who "need" that 6000lb pickup truck when they decide to haul something every 2 years.
brokencase wrote: Thu Jul 09, 2020 9:14 am But if for some reason you needed a new rotor while you are out on the road then you will have to go find a drill press!
This is probably the biggest logical falacy against this "upgrade". The majority of us who modify our vehicles also inspect them on a regular basis. If you have a catastrophic failure of the disc, you're not replacing it on the side of the road.

The nice thing about the 2012+ Focus is the brake mounting, both offset and mounting height, are identical to the Scorpio. The part I don't personally like is the mounting casting on the Scorpio is a lot thinner than the XR making for less material if you drill the mounting holes to the Focus 14mm bolts. I've done a couple sets of these where I simply turned a set of thread adapters so they would be flush with the caliper, then just use a stock mounting bolts.
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Re: 11" Brake Rotor

Post by john keefe »

Thread adapters... smart solution. JOC, You're turning down the female "hub" of the adapter, but how much material do you have left on the hub to act as a head/block/flange after ending up flush with the caliper? Or is it basically just a solid heli-coil at that point with no flange?
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Re: 11" Brake Rotor

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timxr8 wrote: Sat Jul 11, 2020 1:18 pm The nice thing about the 2012+ Focus is the brake mounting, both offset and mounting height, are identical to the Scorpio.
I found when mocking up the 2012+ Focus rotor and caliper on the Scorpio knuckle that I needed one thin washer to get the caliper centered over the rotor. It wouldn't foul the caliper without it, but I'd rather have it dead-center. But otherwise, yea, it's like the guy at Ford who designed these brakes has a Scorpio at home that needed an upgrade. :mrgreen:
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Re: 11" Brake Rotor

Post by Ed Lijewski »

Tim: time to delete this "1988 XR4Ti Duratec project car".


Tim wrote:
I'd argue it's the increase in speed and size of the cars.
Well, the Scorpio in comparison with today's SUV/CUV et al luxobarges is smallish in every way. So, those things might need a few mm larger rotors, but that logic doesn't directly apply to the Scorpio.

So Brad, time to take your Swimmer to a track to test its 60 mph to zero times. Everything else is just bench racing.

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Re: 11" Brake Rotor

Post by brokencase »

My Scorpio stops fine. What I really need is for it to go faster.
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