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8-pot brake kit on ebay


jase_93tt

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I haven't read the whole thread - so apologies if this has been answered already. But what effect do these brakes have on your ABS? I know that on 911s if you fit turbo big reds the ABS can't cope - the braking power is far more than it was programmed for and the wheels will lock.

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Why would it be crap in comparison to a different brand?

What could be the quality differences?

My post is not ment to be offensive to you.

 

 

Poor caliper rigidity, too many pistons, lack of pad choice, probably poor material for the castings (if they don't say anywhere what it's made of assume it's iffy stuff... :))

 

The 10 pot ones mentioned in another post are just barmy. One is trying to reduce pad heat into the caliper body and fluid, not increase it, the more pistons you have the more heat paths. So long as you have enough to stop any severe pad taper wear you have enough. The more holes in the caliper body casting or billet sections the less rigid it becomes. Name any serious race car manufacturer using either of the 2 makes in question?? Name the ones using Alcon, AP Racing and Brembo :)

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We are not driving race cars and we do not have a sponsored race budget either. How is a small up and coming UK company supposed to compete if you only compare it to big name brands and whether or not racing teams use them. :search:

 

By approaching race car manufacturers who now have to build control formulae cars to tighter and tighter budgets, more and more are sourcing parts from OUTSIDE the UK, which was pretty much unheard of 10 years ago. If they offer a cheaper product (which seems to check) that works well (?), with good lead times (?), and a good choice of pads (?), then they will sell them. Maybe some, even most of the (?)'s should be (X)'s?

 

Alcon was a small up and coming company once, with ex AP employees. They offered a competitive product at a competitive price, and made AP's notoriously bad lead times look as terrible as they were. They became bigger... Rest assured, in the current race car manufacturing climate, if they have the right product at the right price all the control formulae manufacturers will beat a path to their door. However, if they are offering a poor product even those working to a budget will not dare spec poor brake, suspension or wheel and hub parts parts.

 

If the budget won't stretch to brand names maybe modding the brake system on a heavy amd fast car used ,presumably, in anger, should be put on hold?

 

On an economics slant, ask anyone who buys cheap (say Hi-Spec) discs how long they last. The dearer offerings are always cheaper, in the long term, same with tyres, clutches, pads, blah blah.

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I haven't read the whole thread - so apologies if this has been answered already. But what effect do these brakes have on your ABS? I know that on 911s if you fit turbo big reds the ABS can't cope - the braking power is far more than it was programmed for and the wheels will lock.

 

That's rubbish, I wrote this article, years ago, which hopefully expalins about imbalanced brake sizes and ABS.

 

 

Brake upgrades can set out to try to achieve several objectives.

The commonest are to increase resistance to fade and or increase

braking effort for a given pedal effort. IE, the pads are

pushed against the discs harder for a given pedal effort than

before the upgrade, or the brakes will stop the car from 100 MPH,

hard, for more times before fade sets in, than previously. The feel

from the pedal, that almost intangible quality, can also be addressed

and sometimes improved upon by brake size, or pad material changes, or

brake flexi hose upgrades to something less squashy than rubber.

It's easy to get carried away by the thought of brake upgrades.

The limitation in most cars as to how short a distance they can

stop in is tyre friction. Leaving aside pedal feedback, and fade,

it is almost certain that a Supra on stock Jap spec brakes will

stop in just as short a distance as one with an AP six pot kit on

it, a Brembo kit, Pauls KAD kit, or whatever. It may not feel to

the driver that it does, but usually such is the case if you just

nail the pedal as hard as you can. The fancy kits may *FEEL* to

stop the car faster, due to less pedal effort, and a better bite,

but in reality, if you hit the pedal as hard as you can with stock

Jap spec brakes, UK spec brakes, AP kit, KAD, whatever, the car

will stop in the same distance. Repeat this test 10 times and stock

Jap brakes may be on fire and long since faded, or the fluid boiled,

UK ones may be very hot and bothered, but the upgraded ones will

probably still be working within pad, disc and brake fluid temp

limits. Add in the intangible "feel" factor, and a desire to brake

as hard as possible, using as little skill as possible, but WITHOUT

relying on the ABS to take over, and for sure a well set up brake

upgrade may well allow more finesse.

 

Herein though lies the rub.

 

Upgrade only the fronts and the brake balance of the stock car may

well be compromised. Let's take stock brakes. You press smoothly on

the brake pedal with (say) 50 pounds force. The car stops fine. 70

pounds, the fronts are just beginning to lock (car makers ALWAYS aim

for the fronts to lock first, as rear wheel lock makes the car very

unstable and liable to swap ends). The rears are doing as much work

as the brake engineers deemed safe to prevent premature rear lock up.

The ABS cuts in, and maximum retardation has been reached. Now, take

a car with big front discs and calipers. Only 40 pounds pressure now

gives a smooth, lock free and powerful retardation. 50 pounds and the

new, more powerful, (for the same pedal pressure), fronts are locking.

The ABS cuts in. BUT, and this is the crux, those original rear

calipers and discs are still well below the caliper pressure where

they are able to achieve maximum retardation without fear of the

rears locking.

 

In other words the FRONT brakes are doing TOO MUCH work, albeit without

breaking into a sweat, and the rears are, to exaggerate a bit,

just along for the ride. The BEST scenario is to upgrade front AND

rear brakes, carefully ensuring the original balance of effort at any

given brake pedal pressure remains as designed, but that the more efficient

front AND rear brakes stay cooler for more hard stops, and that old

intangible "feel" from the brake pedal is improved, at lower rates of

driver effort on the pedal. The latter may or may not be good or

desirable, and can be engineered out by changing BOTH front and rear

caliper piston sizes, or pad areas. In a race car the balance would

be adjustable via 2 brake master cylinders, with a driver selectable

change in mechanical leverage effort between front and rear brake circuits,

one cylinder operating the front brake calipers, the other the rear. This

can also be achieved on road cars, but to do so is usually complex and

expensive, especially if ABS and brake circuit failure safeguards are to be

maintained. It is far easier to calculate the caliper and disc sizes, along with

pad area and compound to achieve this, as near as available off the

shelf equipment will allow.

 

Caveat. I said before makers engineer more effort on the front brakes to

encourage straight line stopping if the tyres are locked up . They err on

the excessive side, as, in the wet, the rear tyres can take a lot more

braking effort than in the dry, due to less weight transfer onto the front

tyres, as they will lock before as much weight is transferred when the grip

of the road surface is reduced. So adding yet more front brake effort worsens

this existing imbalance, especially in the wet. If it were not for the

ABS the front wheels would be locking up very early. On the Supra a

relatively sophisticated ABS allows some effort to be taken off JUST

the fronts, and an artificial and very inefficient balance is returned.

On cars with lesser (1 or 2 channel) ABS, or no ABS at all, a brake

upgrade on just one end of the car can be lethal.

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I think my bias can be backed up with cold hard facts in this case? :)

 

what is your veiw on drilled or slotted disc's, i know the drilled ones are meant to be prone to cracking ?, but some of the big brembo kits only have the drilled disc's, no option of drilled

 

Brembo 14.0'' Big Brake Kit for 1993-98 Supra - Front Kit

Part # Br 1B1.8003A

This is the same kit as above except it has 14.0" rotors & Ferrari F50 calipers & stops even better (hard to believe!!). The actual kit is pictured.

For super-sized pictures of the actual kit with different caliper colors click here.

 

Please note that 18" wheels are required for you to be able to fit these rotors & calipers underneath your Supra. Please note that on this kit the rotors a cross-drilled only, not slotted. Brembo does not offer these in slotted or cross-drilled and slotted. They are available only as pictured here.

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Heat transfer and pistons, could it be possible that all those small diameter pistons "surface face to pad" area is only equal to four large pistions surface area?. Has anyone measured?

Be interesting to see an experiment to check brake fluid temps after the same amount of braking, (obviously have to be done on a test rig) a proper test of how much heat was being transfered.

 

Chris comments on brake performance, i have to agree that the Uk caliper with a decent pad stops the car very very quickly, but gets it tight on extended track work. I was able to get 600degree pads to fester at the edges, so 800 sounds a better bet, but 600 is fine for any road use. Big brakes front and rear has got me dreaming of a very fast ring lap :)

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D2 also states on their website

 

When the components of the kit are worn, such the brake disc or brake pads, AP parts can be fitted onto our brake kit.

 

Also, the brake pad and the following well-known brands AP, FERODO, MINTEX, EBC, PAGID, CARBON METALLIC and HAWK can fitted onto our kit.

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I still see no reason to regard my brakes as rubbish. They are AP copies and I also have the correct size rear set up to have correct (or as close as possible) brake bias. As I said I do not do nor do I have a desire to do track days so for me the KAD's serve their purpose well. I have had to do a few high speed stops one after the other on the stock brakes and suffered from fade. I also had the same problem with my Soarer which also had the stock supra TT brakes.

 

I have yet to have any problems with my KAD's and consider them to be a good value for money upgrade for my needs.

 

Mind you if I was doing or planning to do some serious track days then maybe a set of Brembos might be a better option but without proper testing to compare all we are going on is one mans opinion.

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Mind you if I was doing or planning to do some serious track days then maybe a set of Brembos might be a better option but without proper testing to compare all we are going on is one mans opinion.

 

IMO you pads would be the single most important factor, I see no reason why your Kad's wouldn't do the job very nicely, when Uk spec with a top grade pad can hack it.

 

People can fit all the calipers and pads they like, however if the pad is numb and prone to fade its going to dissapoint.

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I have Ferodo's on there at the moment and they seem to be fine for my needs. I will try another make/compound next pad change to see what difference there might be.

 

I would prefer a pad that does not squeak at low speeds and that will not turn my wheels into dust collectors. :)

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the holy grail then

 

 

Endless CCX or CCR for very hard track use.

 

I was able to drive over 1000 miles on ccx including 5 very hard laps of the ring before washing my wheels. I had NO black dust. I had a light layer of red dust and thats it. The also trip included many hours of autobahn driving 140 to 180mph and some rather hard stops.

 

You wanted the holy grail, you can have it now. Envy had a group buy on endless recently. Quality doesnt come cheap though.

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what is your veiw on drilled or slotted disc's, i know the drilled ones are meant to be prone to cracking ?, but some of the big brembo kits only have the drilled disc's, no option of drilled

 

Brembo 14.0'' Big Brake Kit for 1993-98 Supra - Front Kit

Part # Br 1B1.8003A

This is the same kit as above except it has 14.0" rotors & Ferrari F50 calipers & stops even better (hard to believe!!). The actual kit is pictured.

For super-sized pictures of the actual kit with different caliper colors click here.

 

Please note that 18" wheels are required for you to be able to fit these rotors & calipers underneath your Supra. Please note that on this kit the rotors a cross-drilled only, not slotted. Brembo does not offer these in slotted or cross-drilled and slotted. They are available only as pictured here.

 

If the disc is CAST with the holes in it, or in such a way as to accomodate drilling correctly, and you want or need drilled discs, no worries. My gripe has been that of cheap discs cast as plain being drilled after manuafcature and sold inappropriately, where the casting is really unsuitable to accommodate holes. Also where people buy "drilled" discs for looks, unaware that el cheapo ones will have a very high likelihood of early cracking, and even correctly made race ones have a more likely chance of cracking. Drilled race discs are for where unsprung and rotational weight take precedence over longevity and short heat dissipation (thermal shock), or where ultimate wet weather braking is desirable, and cracking is expected and tolerated. Pic in link below is of a 1 track day old AP drilled disc from my old R33 GTR Skyline, used in the wet at Oulton. I would consider this normal and acceptable. The Brembo ones you cite are good, and correctly made, although I fancy the drilling is 99% marketing department driven :)

cracked1.jpg

cracked2.jpg

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