"H6" rear brake upgrade

[Huffer]

So I may be having to do this in the next wee while, so I thought I would do some comparos.

Basically, the H6 brake upgrade is simply a large rotor - 11.4" - with a caliper mounting bracket to allow the existing single pot/piston caliper to fit over the larger rotor.
The stock dust shield is removed and NOT re-installed. It will be too small for the larger rotor. Unless you are a using the car for rallying, the dust shield is not necessary for street use.

YOU NEED TO CHECK YOUR SPECIFIC APPLICATION.
I'm doing this for a 98 GT wagon with disc brakes.

I got some prices from my fav. OEM parts dealer, http://www.subarupartsforyou.com and compared them if I was picking up replacement parts from a local Autozone store:

SUBARU H6 Brake Upgrade
SUBARU:
Description: REAR CALIPER BRACKET ONLY FOR 2000-2004 LEGACYS ALL (item 9) same part number for left or right
Part No.: 26625AE000
Fits Model: Legacy
Year(s): 2000-2004
Shipping Weight: 5
Price: $55

SUBARU:
Description: BRAKE DISC REAR ROTOR FOR 2005-2009 LEGACY GT and H6 (vented) ALL left or right same number sold individually
Part No.: 26700AE081
Fits Model: Legacy
Year(s): 2005-2009
Shipping Weight: 18
Price: $79

TOTAL SUBARU PRICE: 2x caliper brackets, 2x rear rotors = $110 + $158 = $268

AUTOZONE:
Description: REAR CALIPER BRACKET 2004 Subaru Outback AWD 3.0L SFI DOHC 6cyl
Part Number: 14-1605
Weight: 2.42 lbs
Warranty: 3 MO
Notes: Right hand side same as left
Price: $24.99

AUTOZONE:
Description: BRAKE DISC REAR ROTOR FOR 2004 Subaru Outback AWD 3.0L SFI DOHC 6cyl
DURALAST Part Number: 31273
Price: $34.99

TOTAL AUTOZONE PRICE: 2x caliper brackets, 2x rear rotors = $49.98 + $71.98 = $121.96

DIFFERENCE: $146.32

Now, AFAIK, that's all that's needed to install the H6 rotors (besides removing the rear dust shields). You don't even need to bleed the brakes.
Someone correct me if I'm wrong!

[KAG]

The difference is most likely because you have the wrong rotors selected from Subaru.

You have chosen the 2005-2009 LGT rear rotors, which are vented and cost more as well as they use different brackets. You want the plain jane 2000-2004 solid rotors, which is what you have selected from Autozone.

[Huffer]

Description: BRAKE DISC REAR ROTOR FOR 2000-2004 LEGACY ALL left or right same number sold individually
Part No.: 26700AE04C
Fits Model: Legacy
Year(s): 2000-2004
Shipping Weight: 18
Price: $77

So $4 diff. :)
I actually wanted to look at the newer 05+ GT/H6 rotors because they're vented. They're still 11.3" so they should work also. But the venting means more heat dissipation.

[Airgne]

get the backing plate so you dont have to use an adapter. backing plastes usally cost cheaper than the adapter. the kartboy adapter for the rear FHI 2 pots it 225+shipping. i got the correct backing plates for 160 shipped.

[KAG]

Description: BRAKE DISC REAR ROTOR FOR 2000-2004 LEGACY ALL left or right same number sold individually
Part No.: 26700AE04C
Fits Model: Legacy
Year(s): 2000-2004
Shipping Weight: 18
Price: $77

So $4 diff. :)
I actually wanted to look at the newer 05+ GT/H6 rotors because they're vented. They're still 11.3" so they should work also. But the venting means more heat dissipation.
OK then, that works.

You'll have to change out the calipers, brackets and everything in order to do the 05+ LGT setup. Solid H6 is brackets, rotors and pads and your done. Your choice :smt002

[rougeben83]

get the backing plate so you dont have to use an adapter. backing plastes usally cost cheaper than the adapter. the kartboy adapter for the rear FHI 2 pots it 225+shipping. i got the correct backing plates for 160 shipped.

Before you do that, ask yourself if it's worth $60 to have to pull the parking assembly off and pull the hub off from each wheel...

Backing plate install:
http://forums.nasioc.com/forums/showthr ... pot+nissan (http://forums.nasioc.com/forums/showthread.php?t=1567707&highlight=2+pot+nissan)

[Airgne]

get the backing plate so you dont have to use an adapter. backing plastes usally cost cheaper than the adapter. the kartboy adapter for the rear FHI 2 pots it 225+shipping. i got the correct backing plates for 160 shipped.

Before you do that, ask yourself if it's worth $60 to have to pull the parking assembly off and pull the hub off from each wheel...

Backing plate install:
http://forums.nasioc.com/forums/showthr ... pot+nissan (http://forums.nasioc.com/forums/showthread.php?t=1567707&highlight=2+pot+nissan)

i have to do a wheel bearing anyways so for me yes. also having tackled and understanding how something works makes me happy. also helps to have the knowledge for when ppl need help.

[Huffer]

You'll have to change out the calipers, brackets and everything in order to do the 05+ LGT setup. Solid H6 is brackets, rotors and pads and your done. Your choice :smt002

Actually the H6 solid rotor is just rotor and caliper bracket. I can reuse my pads as the caliper doesn't change.

[rougeben83]

You'll have to change out the calipers, brackets and everything in order to do the 05+ LGT setup. Solid H6 is brackets, rotors and pads and your done. Your choice :smt002

Actually the H6 solid rotor is just rotor and caliper bracket. I can reuse my pads as the caliper doesn't change.

while youre in there, you might as well get a more aggressive pad...just saying.

[Airgne]

for the 00-04 gt the rear braket is the same as the H6?

[jamal]

all US 00-04 legacy rear discs are 290x10mm

H6 brackets do not work with pre-2000 calipers.

You only need new backing plates or adapter brackets to install 2-pots

I should probably copy/paste this into a new thread:
http://forums.nasioc.com/forums/showthr ... ?t=1265631 (http://forums.nasioc.com/forums/showthread.php?t=1265631)

[Huffer]

I should really update this, but I ended up ordering a pair of fully loaded rear calipers for the 2004 Legacy GT. I combined this with a pair of new EBC slotted rotors (which were cheap from a friend).
This combo brought me OEM pads, OEM calipers, OEM brackets plus the EBC rotors.

Plug n play, bleed the brakes and good to go.
Just means that now when I buy new brake pads I have to remember that I have 2004 calipers on the rear, due to the pad shape.

[Baddog]

What I am curious about are the H6 calipers any different then the WRX caliper?

[Huffer]

Check the part numbers and that will tell you if they're different.

[Baddog]

Great answer! I have.

However all I am getting on google is people CLAIMING the H6 rear upgrade is just brackets and rotors (which I already have) but the damn thing nose dives like hell even with a mid-grade pad. So I was curious if someone KNEW if it was actually bigger or not.

However maybe you can find something on google that doesn't lead to a dead end?

[geckoboy86]

Im on 03 WRX brakes, I've been told by a few WRX owners and shop owners that all I need is the rotors and the brackets...Calipers will bolt up and the pads are the same.

Looking at AutoZone's website, 02-03 rear WRX pads are the same shape as the 00-04 rear Legacys. The calipers are different parts in there system but I'm told that all newer gen calipers share the same mounting specs (like location and distance between).

[Baddog]

Yeah I have 04 WRX calipers with the H6 caliper bracket and rotor installed.

[geckoboy86]

Was the pad the same?
Does your nose dip as badly now?

[Baddog]

Yes it dips even with my 04 sti struts and GF210 springs.

[jamal]

Was the pad the same?
Does your nose dip as badly now?

The pad fits in the bracket. So the "H6" upgrade uses D770 (02 wrx) pads no matter what calipers you use with them.

Adding rear bias will slightly decrease brake dive, but it is much more a function of the suspension geometry and spring rates than anything else.

going from stock LGT brakes to WRX front/H6 rear has no change on bias.

[Huffer]

^^ what Jamal said - the H6 brake upgrade is essentially just applying a bigger rear rotor to Car X. The caliper remains a single piston caliper, but the bracket itself extends radially outward about an inch. The larger rear rotor adds additional surface area which aids in dissipating heat under heavy braking. This helps prevent brake fade.

If you increased your front brake size and did the H6 brake rotor upgrade, then all you have done is add additional unsprung weight to the vehicle, but your brake bias hasn't changed.
Nose dive is created by braking, but the prevention of is going to be up to your suspension, not your brake system.

[Baddog]

^^ what Jamal said - the H6 brake upgrade is essentially just applying a bigger rear rotor to Car X. The caliper remains a single piston caliper, but the bracket itself extends radially outward about an inch. The larger rear rotor adds additional surface area which aids in dissipating heat under heavy braking. This helps prevent brake fade.

If you increased your front brake size and did the H6 brake rotor upgrade, then all you have done is add additional unsprung weight to the vehicle, but your brake bias hasn't changed.
Nose dive is created by braking, but the prevention of is going to be up to your suspension, not your brake system.

Then I must have added unsprung weight. Factory L brakes are garbage. Very VERY unsafe and should have NEVER been put on a 3000+ LBS car.

I have 04 STi struts with Tannbe GF210's.

[TexasLegacy2.5GT]

Baddog, did you use the OEM rear brake lines from your Legacy for the H6 rears?

Also, do you think a stiffer suspension (even more then you already have) would prevent that annoying nose dive?

[Baddog]

I used 2nd gen leggy brake lines. Stiffer suspension would probably help a lot. I did this upgrade on the girlfriends car and its much worse then mine

[Huffer]

^^ what Jamal said - the H6 brake upgrade is essentially just applying a bigger rear rotor to Car X. The caliper remains a single piston caliper, but the bracket itself extends radially outward about an inch. The larger rear rotor adds additional surface area which aids in dissipating heat under heavy braking. This helps prevent brake fade.

If you increased your front brake size and did the H6 brake rotor upgrade, then all you have done is add additional unsprung weight to the vehicle, but your brake bias hasn't changed.
Nose dive is created by braking, but the prevention of is going to be up to your suspension, not your brake system.

Then I must have added unsprung weight. Factory L brakes are garbage. Very VERY unsafe and should have NEVER been put on a 3000+ LBS car.

I have 04 STi struts with Tannbe GF210's.

The factory L brakes are 2 piston design, right? Then it's your pads not biting properly or old fluid. They actually work very well if they're in good shape and the pad is appropriate for the driving style.

[Baddog]

^^ what Jamal said - the H6 brake upgrade is essentially just applying a bigger rear rotor to Car X. The caliper remains a single piston caliper, but the bracket itself extends radially outward about an inch. The larger rear rotor adds additional surface area which aids in dissipating heat under heavy braking. This helps prevent brake fade.

If you increased your front brake size and did the H6 brake rotor upgrade, then all you have done is add additional unsprung weight to the vehicle, but your brake bias hasn't changed.
Nose dive is created by braking, but the prevention of is going to be up to your suspension, not your brake system.

Then I must have added unsprung weight. Factory L brakes are garbage. Very VERY unsafe and should have NEVER been put on a 3000+ LBS car.

I have 04 STi struts with Tannbe GF210's.

The factory L brakes are 2 piston design, right? Then it's your pads not biting properly or old fluid. They actually work very well if they're in good shape and the pad is appropriate for the driving style.

You're kidding right? Factory L brakes are single piston calipers. Using ATE superblue and axxis pads.

[Huffer]

My bad, that's why I asked if they were. Maybe the later L models have the 2 piston brakes.

[Baddog]

I could see that in the 2000+ models. However no 90-99 L's had 2 piston calipers (maybe 99 is an exception).

[Wiscon_Mark]

My bad, that's why I asked if they were. Maybe the later L models have the 2 piston brakes.

They didn't get dual piston front calipers until 2000 with the heavier BE/BH chassis.

FWIW, Baddog, all BD/BK L models were around or lower than 3000 lbs. And I don't feel like my vehicles single piston brakes are unsafe. With the ABS off, I can lock the wheels up on dry pavement, and I do have pretty good tires. Perhaps you had/have a fading MC or some other issue? Curbweight on my "Outback" is 2990.

[TexasLegacy2.5GT]

I did the H6 rear upgrade on my 99'LGT sedan the same time I upgraded all 4 wheels to 235/40R17. The feel on the braking is just unreal now. I'm thinking about doing the 4 pot front brake upgrade soon.
https://sl-i.net/FORUM/images/imported/2012/07/AAD5C829-1.jpg

https://sl-i.net/FORUM/images/imported/2012/07/583F052F-1.jpg
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