everything i have found on this topic indicates that regular WRX pads are used with the larger Outback rotor. that means that part of the rotor isnt event touched by the pad. Is a larger pad that covers the entire rotor available to increase rear brake power?

 

It's the same pad but since the rotor is bigger there is more surface to sweep and more metal for a heat sink. It's similar to the difference between the US WRX front rotors and the RS ones. Same pads, but if you look close at the rotors there is a half inch or so on the WRX fronts and Legacy rears the hub thats not touched by the pad.

I have the details here:

http://www.scoobymods.com/forums/sho...=&threadid=814

 

As the effective radius (rotor) increases, so does overall torque. A larger rotor (all things otherwise being equal) stay cooler as well.

The "H6" upgrade will effectively move some brake bias rearward.

I'll be trying this upgrade very soon.

Big Sky

 

Hmmm maybe me, too. Seems a cheaper way to improve rear performance to balance out my front upgrade. Thanks for the link, Peaty.

 

I've done this upgrade and it's perfect for in my case track days and driving school.

Imagine getting on to the track and as your coming up to the straight you start to accelerate. Your going 50MPH, 60MPH, sooner or later you realize that you are going about 110MPH and there is a hairpin turn coming up! Now you need to brake and slowdown FAST!

Under the stock braking system the car will dive forward quite a bit and at those high speeds of over 70+MPH the rear end of the car will wiggle a bit and if you turn the wheel slightly during this time, watch out!

By adding the larger rear rotors with new caliper brackets(to accomidate the larger rotors), you just added about 10% more braking force to the rear thus reducing the front end dive of the factory WRX braking system. This makes less butt wiggling, and more confident braking.

For under $200, you can't go wrong.

 

That's exactly what I wanted to hear! I'm also going to put same pads in the rear as well (Ferodo DS2500's), no wiggle for me!

 

thanks peaty.
i saw your how-to on scoobymods. good pics.
i have also noticed that rear end wiggle and nosedive when braking from over 100mph at the track. now that i have grippier Carbotec bobcat pads on the fronts, i expect that problem will be magnified at the track. i am convinced that the H6 upgrade will help increase the rear brake bias, but i am now wondering if putting more aggressiive pads on the rear (solid) rotors may also cause rotor meltdown. has anyone out there run track pads on stock front rotors with the rear H6 upgrade AT THE TRACK? if so, which rear pads were used, and did the rotors survive?
as i have mentioned in other posts, i saw track pads (front only on stock rotors) melt the rubber boots of the brake system and fracture the rotors on a friend's WRX. so how much extra heat will this larger rotor take?...track experienced drivers' responses please.

 

The best I did was Porterfield pads up front with Axxis ultimates in the rear. I have also used sotck pads in the rear with no ill effects. The rear actually does not get as hot as the front(obviously...) It's a non issue as far as temp goes.


A good example of this is Gary Sheehan and his USTCC WRX. He has gone to a Stoptech brake kit up front and the rear braking system still remains stock, although I'm sure there is some sort of aftermarket pad in there.... That man knows how to drive, and drives his WRX like he stole it.

 

I don't belive temp will be an issue either, thus my decision to put a smidge more bite in the rear (the DS2500 doesn't have a super agressive bite, coeffecient around 0.48).

I do have a duct project in the works for the front however.

Big Sky

 

yes, front duct project sounds good. I have been cooking up a do-it-and-leave-it fog lamp removal duct project too. check this out: Lowes hardware has shop vac parts. yes, i said shop vac. for $18 you get 8 feet of high quality 2.5" black plastic tubing. the leaf blower attachment ($4.88) has a 45 degee bend for directing the air at the hub. there are other attachments which could be frankensteined into all kind of clever uses, the large floor attachment is basically a huge air scoop that fits up to 2.5" tubing. do ya see where i am going with this?? all this stuff is durable enough to drive screws or rivots through, and wont crack off when a little snow or ice gets up in it. ill post pics when i get mine done. there is no way im going back to the track without front brake ducts-i have seen what race pads do to stock rotors and calipers.

 

I'm looking at doing the brake upgrade too. Where is a good place to get the parts?

 

www.subaruparts.com

 

i asked the subaru dealer parts guy if he thought this brake upgrade would void my warranty, and he said "probably". anyone know if SOA will void the entire car warranty if the dealer discovers this mod? i figure the worst thing that could happen to the car is some othe rear brake component (most likely a rotor, pad, or hub) could have a problem. even so, i wouldnt bother the dealer about fixing it anyway. DIY.
anyone know how dealers react to this upgrade?

 

They can't void the entire warranty. The most they can deny warranty on should be the rear brake components.