I have been wanting to get ahead of the curve with my brake system. I read where many builders are experiencing weak braking with the OEM hardware and no power brake booster. My donor is 2004 Impreza wagon N/A. After much research I find that oversized rotors can be bolted on with the aid of taller caliper brackets. While I am not completely finished I believe my front brake hardware is fitting as expected. The Rear is another story. My donor has 170mm parking brake drum (hat section). Using information from other subie sites there is a popular "H6" rear brake upgrade. I found on-line a print from Brembo that shows the correct disc O.D. and 170mm hat section. This print is titled with the Subaru OEM part number 26700AE04C yet I have ordered this part (non brembo) based on the Subaru OEM number and each time I receive rotors with 190mm hat section.
Has anyone else had this experience? Has anyone else found the correct rotor to fit this larger 289mm disc size with 170mm hat? I'm not really budgeted for $1,000 willwood hardware.
Have you considered just upgrading your brake pads to see what you think?
After some autocross and street driving, I feel that our braking is sufficient with just upgraded pads (EBC Yellow Stuff) and OEM 02 WRX hardware (plus FFR clevis mod). It requires more pedal effort for street driving than your average car with a booster, which can make it feel like it's not stopping well, but the brakes are strong enough to lock up even sticky race tires. I'm not very strong or large, and I do not have any problems stopping the car.
If it's more about the reducing the pedal pressure you have to use (vs the actual stopping ability), then I think looking into adding a booster would be the best option. I think some others on the forum have changed the master cylinder size as well. With upgraded pads that are bedded in, the car has plenty of actual stopping ability without either of the above.
I know I didn't really answer your question about the rotors (I don't know since we didn't upgrade anything), but hopefully I helped on the budget side of things and through offering some real world experience.
Tamra
Building 818SR #297 picked up 10/25/14 with Andrew (xxguitarist)
First start 12/21/14, First "drive" 1/17/15 First Dyno at EFI Logics 3/7/15- 310whp at 15psi for break in, full spool by ~3500rpm! First autocross 3/29/15
1st Registered 818 in Connecticut 7/24/2015. 9 months - 1 day from kit pickup!
Have you considered just upgrading your brake pads to see what you think?
After some autocross and street driving, I feel that our braking is sufficient with just upgraded pads (EBC Yellow Stuff) and OEM 02 WRX hardware (plus FFR clevis mod). It requires more pedal effort for street driving than your average car with a booster, which can make it feel like it's not stopping well, but the brakes are strong enough to lock up even sticky race tires. I'm not very strong or large, and I do not have any problems stopping the car.
If it's more about the reducing the pedal pressure you have to use (vs the actual stopping ability), then I think looking into adding a booster would be the best option. I think some others on the forum have changed the master cylinder size as well. With upgraded pads that are bedded in, the car has plenty of actual stopping ability without either of the above.
I know I didn't really answer your question about the rotors (I don't know since we didn't upgrade anything), but hopefully I helped on the budget side of things and through offering some real world experience.
I agree the OEM setup with the 0.5 inch adjustment in the push-rod location is enough for me (EBC Red Stuff not broken in yet). You do need to press harder since they are manual brakes but its not terribly hard to lock up the wheels. FYI without the pushrod adjustment stopping was a bit scary.
The spec sheet you included doesn't state the Parking brake size and I am already returning 2 orders that arrived with 190mm. Because my donor was an Impreza wagon it came with 170mm hat and 10mm solid disc. Most if not all of the WRX came with 190mm hat and vented rotors. As it turns out I have rear calipers to fit both the solid (Impreza) and vented (from my JDM front clip) rotors. That would be ideal to have the larger vented rotors that also fit my 170mm Pbrake. Was this enough of a problem (for you) that you are absolutely certain this part number is 170mm? Then again at $18 It's worth ordering one just to check it out. Thanks
now if I could just figure out how to load a photo for my avatar.
The spec sheet you included doesn't state the Parking brake size and I am already returning 2 orders that arrived with 190mm. Because my donor was an Impreza wagon it came with 170mm hat and 10mm solid disc. Most if not all of the WRX came with 190mm hat and vented rotors. As it turns out I have rear calipers to fit both the solid (Impreza) and vented (from my JDM front clip) rotors. That would be ideal to have the larger vented rotors that also fit my 170mm Pbrake. Was this enough of a problem (for you) that you are absolutely certain this part number is 170mm? Then again at $18 It's worth ordering one just to check it out. Thanks
now if I could just figure out how to load a photo for my avatar.
Hi CNC
My forester donor was 170mm also.
I'm sure they are 170mm
That rear disk is for an 06-07 wrx and it has 170mm ebrakes.
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Originally Posted by Tamra
