I am trying to figure out what brake setup would best suit my needs to slow an FD down from 200+ mph without melting. The car is a street car, so the brakes must be functional for street use, and will need to be able to handle the friction and heat created from slowing down from a top speed run. I was looking at the Type RS/RZ brakes, but also looked into the Racing Brake setup, as well as the new Wilwood Superlite 6R's. Again, I don't track or road race the car, but I am also worried that the stockers will simply not be up to the task.

Also, what about the rears? Stock? RB upgraded rotors/pads with stock calipers?

Thanks in advance for any input.

 

What kind of braking needs done at the end of the TX Mile? Just out of my own curiousity, never been there. I would assume with some of the speeds achieved there that there is plenty of runway left and you wouldnt exactly need to panic stop down from 200MPH at the end.

 

It's not as long as it should be, so no...it won't be a panic brake, but it's definitely not long enough to slow down gently. I don't want to bother with a chute, but my goal is north of 225mph, so I will be getting close to the group of cars throwing chutes.

 

So how does a set of stock RZ brakes compare with a set of Racing Brakes or comparable aftermarket BBK? Dimensions are fairly similar from what I gather.

 

Hey Scott,
FWIW, I have a RacingBrake setup you can check out when getting all the other pieces. Not forsale, but you can see it in person.

 

RZ brakes, good pads, fluid. Should be plenty enough for a straightline stop.

 

Carbon ceramic disks and pads my friend...

 

my friend has had his FD north of 180mph a couple of times, and it actually slows down fairly quick on its own. @180mph, brake ducts actually will work, so you should use em, and actually they should be pointed at the wheel bearings too.

i'd think RZ brakes would be the minimum spec (that's what my friend has). you should put good pads on it, i'd recommend performance friction, they have compounds for all kinds of applications, and can do small batches (we've got honda pads in a compound they don't even list on their website).

you could actually play engineer and do a little math, i think you take mass of the car x speed and get BTU's, then you can take BTU's + time and the size of the rotor (or whatever) and see if you're ok, or need to bring extra underwear, and a fire extinguisher

 

You're going to record this event right????

 

I have no issue spending money on brakes...I was just curious since the sizes were almost identical. If one were to put new rotors, good pads, Motul fluid, SS brake lines, and brake ducts on an RZ brake, would it work anywhere near as good as an aftermarket BBK setup? If not, I'll order a set of brakes...but if these can work, I may grab a set. Just curious if anyone knew if these brakes were much of an upgrade over stock, and if so, by how much.

 

All aftermarket calipers and disks are supposed to do is hold more heat and be more consistent over multiple braking events so that braking is more consistent. The FD is not a brake challenged car, and if you want to worry about stopping distances, good pads/decent rotors and good tires would be the actual components "stopping" the car.

 

if driven 10 10ths the FD brakes are nowhere near adequate. i can run an FD out of brakes in two laps on a road course. this would be w race pads.

if you are going 200+ at the Tx Mile you really need an actual set of brakes. given it will take about 1000 rwhp to do 225 and knowing what that setup costs spend a few bucks more and you will actually be able to stop.

braking effort is not linear. it takes alot more than 12.5% additional capacity to stop from 225 V 200. plus the new track sort of sucks, er, is challenging in the runoff area.

the primary problem w the FD is lack of adequate front rotor mass. the RB rotors are monsters and are extremely well engineered.

the RB rear upgrade is both excellent and necessary.

you need to retain the proper balance of braking effort front to rear or you will be going for a lateral ride. at 200 the ride will also include lots of barrel rolls.

front rear balance is as important as capacity. you need them both. the RB 4 corner package retains proper balance. check out the RB thread and take a good look at the comparative pics of the stock FD rotor and the RB rotor. the 4 piston RB front caliper will work perfectly for you.

i hope to be at the Texas Mile Oct 26-28 and will be running my RB setup.

do it.

howard

 

Yea, I have no issues spending money on safety....just didn't know if the RZ brakes were sufficient, or if another setup would be better suited to my application.

 

chute?

 

History shows that 200mph+ RX-7s like to flip.

Are you sure you can keep the front end down and avoid death?

The racing beat FD had a full under body pan:
This FC flipped. Minimal aero mods: Dandy Tanaka - Speedhunters

 

If you look at pictures of the original hood, it did not have reverse vents like the Mazda Speed
hood which reduces lift under the front. Without proper front wings/spoilers, all that air still pushes the nose upwards.
The air going into the nose needs to escape another direction instead of downwards.
The car was also going around 240 mph.

 

If you actually researched what happened you'd realize it wasn't completely an aero problem... I doubt many cars will stay planted sideways at those speeds.



If you insist on upgrading to a big brake kit you could always consider the SakeBomb Garage brake package

https://www.rx7club.com/suspension-w...-pics-1010015/

But as Miata_mx5 said below the RZ brakes should be plenty for what you're looking to do and a "bbk" shouldn't be necessary.

 

I will see you there at the Texas Mile!

I'm hoping for 170/180ish (~515hp).
FWIW, I'm running StopTech fronts with RZ rear brakes. I was planning on just running my street pads.

From 200mph, with RZ brakes, definitely would want track pads that work reasonably well when cold (Carbotech XP10 are IMO OK in this regard). From 225mph, BBK a very good idea....

As mentioned above, the energy you have to dissipate goes up with the SQUARE of speed.

200mph => 31% more energy vs. 175mph
225mph => 65% more energy vs. 175mph, 27% more vs. 200mph

 

I like the Viper V10 in the engine bay at 3:53.