Sumitomo 4 Piston WRX caliper upgrade

[GC GTS Aero Kit]

Hi All I was told today that the early 4 Piston Sumitomo Caliper from 1999-2006 will bolt straight onto the 86 braking system and run with the standard rotor. I picked up some DBA5000 series rotors for a steal and I was thinking of using these as a cheaper upgrade to a BBK.

Has anyone fitted them successfully?

[TOMIMOTO]

Just like the Brembo's they're going to be on backwards. You're going to have to swap the bleeder over to the other side.

[GC GTS Aero Kit]

Thats ok just got told by the brake shop the rotors and the calipers are identical to 1999 - 2006 WRX and current Subaru Forrester and they should bolt on cause they use the same rotor part and caliper bolt separation

[Racecomp Engineering]

Originally Posted by TOMIMOTO

Just like the Brembo's they're going to be on backwards. You're going to have to swap the bleeder over to the other side.

The pistons on these calipers are not staggered, so you don't need to do this (when installed with the bleeders at the top you're still good).

- Andrew

[choi0706]

interesting...

[Dave-ROR]

Originally Posted by Racecomp Engineering

The pistons on these calipers are not staggered, so you don't need to do this (when installed with the bleeders at the top you're still good).

- Andrew

What he said.

However, this doesn't fix the real need for the front brakes IMO.. a bigger heatsink.

[Racecomp Engineering]

Originally Posted by Dave-ROR

What he said.

However, this doesn't fix the real need for the front brakes IMO.. a bigger heatsink.

Agreed. You get a lighter, stiffer caliper and shift bias slightly rearwards with these, but not much else. The caliper itself is better but you're not going to reduce fade much at all.These calipers on a slightly larger rotor (maybe LGT rotors) would be neat but I'm talking out of my ass on that one and that'd probably take some custom work.


EDIT: I'm wrong on the bias change, the rear FHI 2 pots shift bias forward. Front FHI 4 pots have no effect on bias.

- Andrew

[gmookher]

Originally Posted by Racecomp Engineering

I'm not sure shifting bias rearwards is a good thing for this car either.

Not at all. The factory bias braking is perfect for braking into fast corners IMHO. I cant say I 'need more brake' if the fasctory brake witht he ferrodo setup were to hold up. Slows me down just fine with my tires, I could see with a bigger wheel that being a concern

[Racecomp Engineering]

nm

- drew

[marco_mc22]

Are these the same as the Wrx Pro ones? Piston size 37mm (1.45in) right?

[malubawla]

I have them and the rears as well, done for the sake of making it faster to swap out my street and track pads. In terms of feel, bite is slightly better and feels easier to modulate pressure. The front are 4 pistons, the rear are 2. Need to use a KNS version 2 bracket for the rear, front bolt on.