Bolt-on Big brake kit

[mnbvcxz97]

Ryan,

I agree - brakes should be only as big as necessary to accomplish the task at hand. The added mass is also rotating mass (as well as unsprung), and many cars accelerate slower with big brakes.

For track days or road racing, they can be helpful, of course.

I also think that many times people report brake fade, it is because they are heating the brake pads to a new high temperature (for them), and this is causing the fade. When I was road racing (years ago), the standard practice was to warm new pads gently for a lap or so, than do one huge fade at the end of the fastest straight. Once they had been cycled like this, they would be fine.

But even if you had driven the pads for a long time (on the street), and got them fairly hot, they would still fade until they had seen 'racing temperatures' for the first time.

So when someone says their brakes faded after a single emergency stop from a high speed, that may not necessarily indicate the need for bigger brakes - the thing to find out is if it does it on the next stop.

Steve

[hockeystyx16]

semi loaded 07 mazda6 calipers with brackets are 88 dollars a pop from advance with a 35 core. then throw your old probe calipers in the boxes and take them back for cores.

[js626lx]

semi loaded 07 mazda6 calipers with brackets are 88 dollars a pop from advance with a 35 core. then throw your old probe calipers in the boxes and take them back for cores.

Hmm... I see $101 with bracket and $50 core. $75-$81 without bracket and still $50 core.

[dillinr]

For track days or road racing, they can be helpful, of course.

Absolutely, and the drawbacks of rotational mass have a smaller effect as the rate of change in speed is much lower as compared to autocross.

And the effect of the un-sprung weight is smaller as compared to the highly transitional nature of autocross.

I have contemplated switching the rotors/calipers when I do track days. Hell I'm swapping pads and bleeding the fluid anyway, so it's just a matter of swaping the brake line and a couple copper washers.

[js626lx]

Has anyone tried the CX-7 calipers yet?

I'm interested in this info as well. Dual piston brakes that bolt right up would be great. I'm thinking they may not as the CX models are a different chassie all together right? But if this is a possibility then it would be more worth it than the 6 brakes.

[v6powered]

do the m6 brakes fit also the mx3?

[charles]

Well i have the speed6 brakes and rotor at my shop now. Once i have a little more free time at the shop i will have pictures and a write up to go with it.

[PGT Mac]

.....I also think that many times people report brake fade, it is because they are heating the brake pads to a new high temperature (for them), and this is causing the fade. When I was road racing (years ago), the standard practice was to warm new pads gently for a lap or so, than do one huge fade at the end of the fastest straight. Once they had been cycled like this, they would be fine. .....

Theoretically speaking, you can do that in an oven. What you are doing in that "one huge fade" is generating enough temperature to complete the lining material cure. Yes with some linings you have to transfer lining material to the rotor to get max friction, but mostly it's temperature.

I wouldn't do it in the house, or in the oven you cook in. You're baking out the solvents in the binders and that's what you smell with new brakes and for sure you don't want that in the kitchen.....

My '06 Mazda 6 went to the junkyard a couple of months ago.....don't know which one.......but there's 2 more brakes out there for the pick'n.

[d15b7]

hi!

yep -- that is called 'green fade'; it happens when new brakes are pushed really hard and have not been properly 'bedded in'. all the racing pads i purchase have special instructions on how to bed them in; they typically explain a series of 'take it up to xx speed, and then brake to xx speed. do this xx times, and then drive around without touching the brakes if possible for xx minutes til they are cool'. this gives max brake pad life, with best performance.

of course, there is also the other kind of 'fade'; what i guess can be called 'while on duty' fade! lol! this happens when the temperature at the rotors/pads exceeds the design criteria for the pads (the pads i use recommend a max temp of around 1500 degrees, and warn that they are ineffective below 600 degrees).

the problem i experienced repeatedly when racing my Probe GT was that the pads and rotors would get SO hot that i would experience extreme fade (pedal sinking to the floor) and that the rotors would crack in very short order (usually in one or two race days) and that the pads would melt and bend into 'bananna' shapes... the temp of my rotors/pads was going way beyond the design parameters, and failures and poor performance were the result. hence, the reason i designed the ReidSpeed BBK (VR4 rotors and millenia calipers). once installed, i now have zero braking problems -- never, ever experience fade! and a big plus is that the pads last many race weekends, and the rotors last many race YEARS! the pads and rotors are now well within their 'comfort zone' with regards to temps, no matter how long the race is.

[PGT97_Racer]

do the m6 brakes fit also the mx3?

I don't think so since MX-3's are a 4-bolt. But you'd have to try. The caliper might bolt up, but you'd have to find a 4-bolt rotor that is the same as the M6 rotor but that has a 4 lug bolt pattern.

[mnbvcxz97]

d15b7,

Absolutely, the green fade is avoidable with proper break-in, and what I suspect most people are reporting in street conditions when they have an unexpected single high speed stop for the first time.

The other fade (the 'oh-shit' fade ) comes on suddenly, and is very scary if you are coming into a slow corner at the end of a long straight - the best you can do is throw the car sideways and say a little prayer!

I have been there many times (not with a Probe) and I always changed my pads and fluid every session on the track - with only limited success (the rules in that series required stock rotors and pads, etc.). That was worrying, annoying and expensive!

For my Probe, I'll definitely put the Mazda 6 brakes on (they are sitting on a shelf right now waiting for the nicer weather) for track days, because that feeling of no brakes when you *really* need them is a part of racing I don't need to experience again! And it might be that even bigger brakes are required (depending on the track and power level).

However, I just posted to this thread because I wanted to point out that like everything else on a car, brakes are a compromise - they must be as big as needed to do the job (i.e. not fade!) but the bigger they are the more they adversely affect handling and acceleration...

Also the energy that must be absorbed by the brakes is primarily the kinetic energy of the vehicle, and this is proportional to the square of the vehicle speed. So a vehicle losing half its speed from 80 to 40 mph on a road course loses 4 times more energy than the same vehicle going from 40 to 20 mph on a auto-X course. That energy is turned into heat, so that brakes get very hot. On the other hand, most road race corners tend to be a little further apart (more in distance than in time, though). The bottom line is that the brakes need to be "big enough", any bigger and you'll slow down....

Steve

[mnbvcxz97]

A few notes on the Mazda 6 '03-'05 brake upgrade:

- the bleed screws are larger diameter than those on the Probe (listed as M7 X 1.0 x 32.0mm on a few websites) so if you are ordering speed bleed screws, you need to get them for a '03-'05 Mazda 6 (M8 X 1.0?).

- the brake hose is just long enough. There's a locating tab on it, and the Mazda 6 calipers have this in a more vertical position, requiring the hose to go a bit further to reach. It fits, and there's little motion in this part of the hose (other than the caliper movement - i.e. no suspension movement) so it should be fine. However, if you were ordering new hoses, it might be worth looking into Mazda 6 lines (I'm not sure if the other end fits).

- as noted above, the rotor/caliper fits easily in the 16" rims.

- the splash shields behind the rotors do not interfere in any way with the rotor or caliper, and while they can be removed with some effort, they can also be left in place. They can easily be bent by hand to be 1/2" to 3/4" further away from the rotor to provide more room for cooling air to circulate.

- brake effort is noticeably reduced, for three reasons: larger pistons mean more pad force for a given amount of pedal force, larger pads mean more friction for a given force, and the pad is further from the axle axis (because of the larger diameter rotor) which results in a given force on the pad/caliper having more braking torque.

- because the PGT (in '97 at least) has a diagonal split on the master cylinder, you will need to bleed all 4 calipers when you are done (since the master cylinder will likely drain in the swap when the calipers are disconnected). Once bled, the pedal feel is very good with the new calipers.

- Hawk, among others, makes performance pads for these calipers: HPS (PN HB472F-650) and HP+ (HB459N-700).

- I haven't tried the spare wheel/tire on yet (to be certain it clears the caliper), but will do this soon and confirm it here.

Steve

[dillinr]

Do the Hawk Pads fit on all rotor sizes??

[mnbvcxz97]

dillinr,

The 03-05 pads certainly won't fit in a Probe caliper - they are way too big (5.19" x 2.34").

On the hawkperformance site, the 06 pads are listed as:

HB549F.702 Disc Brake Pad; HPS Performance Street w/0.702 Thickness; Front;

the 04 pads are:

HB459F.700 Disc Brake Pad; HPS Performance Street w/0.700 Thickness; Front;

So they certainly have different part numbers, suggesting they are not interchangeable.

Steve

[LoueyB]

Ok I know that I am a total idiot at times.. but please bear with me.

Will upgrading to Mazda 6 brakes affect my ABS at all? (I have no idea how the ABS system works)