OGRacing

iTrader: (1)

Right. just so we are on the same page. the tire Doesn't change the Tq output of the braking system. Changing the MC will affect tq. But because you have a single MC system, changing the MC won't change Tq Balance. FYI a larger MC actually decreases Hydraulic advantage and Tq. a smaller MC increase Tq but it also increases the stroke. In every pedal there is a point of no return, when it comes to mechanical leverage. it's generally at 6 o'clock (straight up and down). If you go too small on a MC your travel will increase, going past that point you're losing mechanical advantage and your pedal will start to become harder.

I was a factory rep For a major Performance Braking systems manufacturer. I know more about brakes then anyone should know.. Dont ask me anything about turbos, i don't have a clue. :P


enough with the boring brake engineering.
Miata's brakes from the factory are very front bias. The majority of this comes from the factory proportioning valve. as you hit the brakes harder it cuts more of the rear flud off. Hypothetical situation as to why mazda does this - if your mom hits the brakes on a wet road, in the middle of town, she doesn't go looping off into some tree. it will simply lock up the front tires and your mom is saved.

if you're in a class that allows it, remove that prop valve and replace it with the flyin miata valve. that's the one i got, i love it. this will remove the choking off of the rear brakes. after that you can run a square braking set up. same compound pad F&R.


If your want to keep your car spec miata legal, then we'll throw a higher tq race pad in the rear to counterbalance the factory prop valve.

sbcrx007

iTrader: (1)

- Correct

Tire compound & width will affect how much torque the brakes can generate without locking up and skidding.

My intent was to mix and match components for the best budget brake system - best braking, no fade, able to run less than "race" level pads (ie, the Stoptechs), balanced front to rear (or at least better than it is now), and be wallet friendly. Such a thing as best is going to be subjective anyhow, but thru trial and error I'm sure there are "best/better/good" options. I figured somebody here has done that, whether they're trying to fit into a class, or just a cheapskate like me!

- No worries, you're talking to an engineer

Agreed on the front bias, that's what I'm trying to correct with some of the options I listed, adding rear calipers/rotors that are further upsized than the fronts. I'm not worried about fitting into any class, I just do trackdays and hpdes. I probably will remove the factory proportioning valve and go adjustable, though it's another thing to fiddle with on a car that's already pretty fiddly... Ideally the brakes would be balanced without having to really choke off flow to the rears, basically running the adj. prop valve wide open.

OGRacing

iTrader: (1)

Finding a Street pad that will take race temps is going to be hard. the Majority of street pads out there contain fillers that are combustible. see attached img. The stoptechs i assume are like the PFC 10 compounds. able to take elevated heat over a autozone pad, but these are still a street pad. you will find the limit on a track day doing multiple 20 min stints.

it's cool to try and go cheap on a race car. the sport is damn expensive. but cheaping out on pads is always going to bite. You might save $20 running a Stoptech or PFC .10 over a set of race pads. When your street pads let go it could ruin a weekend that you have over $900 invested.(think track fees + hotel= food ect..)

the cheapest way of going is running the prop valve & 1.8l brakes F&R.
not mazdaspeed brakes, finding race pads for mazda speed brakes is a pain.

sbcrx007

iTrader: (1)

That's a great picture!

I had seen a spec somewhere for the stoptech performance pads, I belive peak temp was 1300 F, that's well into race pad territory. I don't know what the friction curve looks like approaching that value ( I suspect it's aleady dropping off rapidly, and pad life is probably awful at such a temp), but I've had them smoldering hot without any fire. I can actually get them hotter on the street with back to back accel/brake runs 70-10 mph (as in rebedding them) than I can on my local track. Obviously that might be different at a more brake intensive track.

Mazdaspeed brakes are NB sport brakes I thought?

OGRacing

iTrader: (1)

Yep they are.
One thing to consider when being cheap you might not be saving any money. My point is replacement costs. I have the trackspeed 11.75 BBK. I have about 100 more hp than most people on this sight (LS1 car). I Ditched the Wilwood rotors that it came with and went with PFC 01 pads and PFC 8x7 rotors. I track my car 2-3 times a month (field rep and my car come with) and i'm on year 3 with the same rotors. I know that allot of spec miata guys go thru pads and rotors allot more often than i do, and they are 350hp less then me.

Braineack

iTrader: (62)

QFT.

If I ever buy a miata again, first thing I'm doing is upgrading the rear brakes and adding a prop valve.

sbcrx007

iTrader: (1)

Looks like my pads are available for both the 1.8 and 1.8 sport/msm brakes. I'm curious which pads aren't available for the sport/msm?

I should also 'splain that I already have 1994 1.8 brakes laying around on my parts car. Sport brakes would come out of my pocket.
So the question still stands, which are the best parts to upgrade to?

OGRacing

iTrader: (1)

the larger the rotor the more tq, also larger rotor will last longer. install that 1.8l kit and add a prop valve.

sbcrx007

iTrader: (1)

Finally got around to actually checking the calipers and pads (was in the middle of a trans/clutch R&R)...
Hornet called it, my pads were indeed frighteningly tapered after 2 track days with boost. This then is no doubt the fantom crappy brake syndrome I've been chasing, probably just wasn't this noticeable before and I wasn't looking for it. Thanks!

On that note, I'm looking at the front brake setup with the Willwoods and Mini rotors that it appears Relte and EO2k pioneered.
MINI 11" rotor instead of Corrado - Miata Turbo Forum - Turbo Kitten is watching you test compression.

Then going to 1.8 sport in the rear, and adding an adj. proportioning valve.

Thank you gentlemen.