jester

Stage 2 Drilled Brake Kit
Stage 2 brake upgrade with drilled rotors for the 2003+ Subaru WRX includes StopTech stainless steel brake lines for front and rear, 3 bottles of Motul RBF600 brake fluid, StopTech Street Performance brake pads for front and rear, and StopTech slotted rotors for the front and rear. StopTech Street Performance is a very similar compound to Axxis Ultimate, except that it has a ceramic heat shield between the friction material and backing plate to help prevent heat transfer into the caliper and brake fluid. FITS STOCK CALIPERS.
$599.00 - Item No. 86-836-02415

Stage 2 Slotted Brake Kit
Stage 2 brake upgrade with slotted rotors for the 2003+ Subaru WRX includes StopTech stainless steel brake lines for front and rear, 3 bottles of Motul RBF600 brake fluid, StopTech Street Performance brake pads for front and rear, and StopTech slotted rotors for the front and rear. StopTech Street Performance is a very similar compound to Axxis Ultimate, except that it has a ceramic heat shield between the friction material and backing plate to help prevent heat transfer into the caliper and brake fluid. FITS STOCK CALIPERS.
$599.00 - Item No. 86-836-02414

Which one do I choose?

SnoHumper

whatever gives you the highest coefficient of friction... huge cross drilled slaughtered rotors with huge (metallic or ceramic) pads bein squeezed by 4 pots.

Kevin M

iTrader: (12)

That's only one part of the braking eqution. Piston size, rotor diameter, mass of the directly related parts, the relationship of brake cylinder piston size to pedal mechanical advantage to total caliper piston size... many many variables. Right now, without a doubt, the most cost effective way to improved braking performance with a Subaru is with the "H6" rear upgrade and Subaru 4 pots up front, for anybody who isn't in serious competition with their car. The next step up is something like a Stoptech BBK matched to your rear brake setup.

SnoHumper

piston size and rotor diameter are part of the coefficient of friction. jester said he never sees any track time so i doubt he will be changing master cylinders or change the mechanical advantage of the pedal.

Kevin M

iTrader: (12)

You're still thinking in terms of trying to reduce braking distance. That's next to impossible to do on a street car on street tires, and a moot point if you can lock up the wheels already, which we all can. Therefore the much more important cosiderations are brake fade and feel, in that order.

Speed Element

iTrader: (39)

Makes sense to just go with a decent pads, rotors, lines and fluid combo for a street car or even most AutoX cars (typically a Stoptech Stage 2 kit handles a 55 second run ok).

Like BAN SUV's said anything after that would be in the realms of matched BBK.

One question I have for the people with H6 upgrades in the rear is if the master cylinder and brake bias is different in the Legacy (it's a little heavier a car!) as I have never checked personally, if they are different this might upset the brake balance and overal braking to handling point of the car when being setup for racing. Like I said just a thought as I have never looked at the braking system on the Legacy and do not know much of how the setup differs on that car to the Impreza.

Mike

Kevin M

iTrader: (12)

The short answer is that brake bias will definitely shift rearward. However, the car comes with so much front bias that I think it's actually a significant improvement for those with some skill at trailbraking. It's unlikely that, say, a WRX or even an RS with stock brakes will become unstable with the H6 rears, provided you've also gone with the de riguer upgraded front pads/rotors/fluid/lines. I'm probably going to have H6 rears on soon (although I have FHI 4 pots, so I don't have a good guess as to how the brake bias will differ from the original stock setup).

Kevin M

iTrader: (12)

Personally, I would base the decision on what to do with your brakes entirely on what class you run in. I wouldn't change classes for the sake of being allowed better brakes, however. So, a stock WRX is allowed pads and fluid changes, but not rotors or calipers. In STX however, brakes are unlimited except that they have to fit under legal wheels. I'm not sure exactly where the line is for Street Prepared WRXs though.

Speed Element

iTrader: (39)

Makes sense although how much of the cars suspension geometry is based on the braking balance and visa versa?

I am just curious as we have all the parts for these H6 upgrades at the shop and I have pondered over slapping a setup on the shop car for a while.

Mike

Speed Element

iTrader: (39)

SM and such really have no limits as far as I am aware.

Most of the car we come in contact with are STX and onwards as far as mods dictate so the Stage 2 type mods and up braking wise are the typical requirements.

I too would not move class just for braking mods.

Mike

Kevin M

iTrader: (12)

SM is indeed unrestricted in any way. That's what class I run in. Good point on the effect braking has on the chassis, but I think it matters a lot more during suspension geometry changes during significant forward roll that occurs under hard braking, rather than the actual braking force at each wheel. That's a pretty involved technical discussion though that revolves very much around a whole lot of individual factors on individually modded cars.

Oh, and my mistake- I believe STS requires factory calipers while STX does not. Have to double check though.

wombatsauce

iTrader: (7)

This is a great discussion.. I have a MY03 Sedan w/ 27k miles and my wear indicators just started screeching. So - it's time for brakes. I am going to get new pads fr/rr and new rotors up front. I have been leaning towards Porterfield R4-S because I do occasionally drive my car in the manner it was built for, I know a distributer, and because I have had good luck with them in the past. I haven't seen anyone mention these though. Any thoughts or comparos between the Axxis gear? I have had okay results with Axxis pads on past Nissans.

Tim: does the pad difference also apply to MY03 cars? I saw my pads last night investigating the noise, and they look like the D929 pads (from memory) and they definitely have the slot in the center (they are OEM). Should I pull them out again and check before ordering anything? Still rockin the grille.. Thanks..

Anyone: What parts are involved in adding the H6 rears? JUST calipers? Rear bias is a scary thing - I upgraded the rear brakes (drums --> discs) in my other car and I need to even out the bias with different pads as it's scary (and fun) in certain situations. I agree that the WRX is very front biased tho. I am thinking to eventually end up with the FHI 4-pots up front, but was wondering what to do with the rear..

That Stoptech kit looks nice with the fr/rr pads, lines, rotors and fluid. If the Axxis pads are good and those are blank (not slotted, drilled or gimmicked in any other way) I would be down so long as they fit my car.

Prolly be about the same $$ as fr/rr Porterfields and cryo Brembo rotors anyway..

Thanks,

Jacob

jester

Is this the correct part # for the stage 2 slotted kit for an '04
wrx: 86-836-02514

If so, how much do you sell for?

-Jeff

Flash N Dash

iTrader: (79)

jester - You have a PM waiting for you!

Thanks,
Brian

Flash N Dash Performance