Well, we're almost there with our new ST-22 rear calipers for the WRX and STi. The first batch of calipers has officially left the building. They will be run on a number of World Challenge BMW's this coming weekend at Mid-Ohio (Turner Motorsports and BimmerWorld). During practice, they’ve had nothing but good things to say, and they’re thrilled with the results they’re getting with the new StopTech rear wheel brake upgrade.

On to the good stuff… You'll see in the first pic that we use our small logo on the face of the caliper, which is taken from the middle of our standard logo on the front calipers. The black anodized version is pictured. The production versions will be available in red, black, or silver paint. We will also be offering black anodized rear calipers, but they will only be available to Subaru owners who already have our front kit with black anodized calipers. Finally, we offer yellow or blue paint for an extra $100 per caliper.



You can see the pad retention system in this next pic...we went without a bridge in this small caliper because it was would have added weight without adding any stiffness in this particular caliper. The shape of the caliper is smaller and forms a much tighter square 'box' than our ST-40 front caliper. As a result, it maintains an extraordinary stiffness even without the bridge. The caliper weighs about 5lbs, and it is made from 2 halves of billet aluminum. It is a 2 piston opposed, fixed design.



You can see in the above picture, that the caliper sort of teeters on the main body when lying at rest on the table. This is because the caliper was designed to integrate as closely as possible with the bracket in the rear, allowing for max wheel clearance. This also allows for the use of less material, which again saves weight.



For the rear of the STi and WRX we will be using an ST-22 mounted on a 328x28mm AeroRotor. This combo provides more than enough heat capacity for pro race applications on the rear of both the WRX and STi, so you can be sure that this setup is BIG enough. Through calculations and testing, we have optimized the piston size of our rear kits to be a direct add-on to our current 332mm and 328mm front kits. The pad shape on this caliper is identical to the one used on the rear of the STi, Track Model 350Z, and EVO. The reasoning behind this is that it provides a wide range of high performance street and race friction. Retail price will be $1795 for the rear big brake upgrade as a stand-alone part. Our initial discussions put the new 4 wheel kit pricing as follows:

WRX Slotted 328mm F ST-40 caliper and 328mm R ST-22 caliper $3590

STi 4 WHEEL KIT PUT ON HOLD DUE TO SIZE OF DRUM IN HAT PARKING BRAKE

Drilled rotors are an extra $50 per rotor.

Now for the big question...when can you get yours?!?!? As per usual, as soon as we announce a release date, we get a call from one of our suppliers saying that they’re running 14 months behind.

With that having been said, rear kits with ST-22’s are being tested on our race cars as we speak. I'll throw out an estimate of 6-8 weeks before everyone can get their hands on them. The response we've had has been overwhelming. We’re thinking of taking preorders in about a month. Talk to your local tuner and get in line for yours...the first run will undoubtedly be sold out almost immediately.

Thanks,
Tim Kelsch
www.stoptech.com

EDIT: For change on status of STi kit.

 

Good stuff! One question though- what exactly is holding the caliper together? No bridge and no visible cross bolts... Is that just an engineering mock-up?

 

Nope, that's the real deal. The bolt holes don't go all the way through the outer half of the caliper.

Tim
www.stoptech.com

 

Ah, and we can't see the inside. Sweet. Now put up the pic of the mounted caliper and rotor like the post says you did.

 

What do you mean?

 

WAAAAYY out of my price range, but pics look sweet nonetheless Great job you guys! Thanks for showing us the love :P

 

how much can we expect a front and rear setup to run?

 

hth

 

wOOt looks gooooooood!

 

Bump for an edit to the original post regarding status of the StopTech 4 Wheel BBK for the STi.

The problem is that the smallest rotor we can currently use on the rear of the STi is a 355mm rotor due to the fact that the drum in hat design of the parking brake. Unfortunately, the 355mm rear rotor will increase rotational inertia and rotating mass too much and is not an acceptable performance upgrade. Using 355mm rotors in the rear will also require the use of 355mm rotors up front. Another problem with the 355mm rotors is that they necessitate 18" wheels, very much a faux pas in the Subaru world.

So what we have now is a new design constraint that our engineers have to work around. One possibility, however remote it may be, is to scrap the drum in hat design of the stock parking brake caliper and use our ST-10 parking brake caliper along with the ST-22 on a 328x28mm rotor in the rear. Whether or not that will prevent the kit from being a bolt-on or from allowing us to price the kit competitively remains to be seen.

Another notable point is that we have also had a 2005 STi in to measure, so we will be working on the four wheel kit for that platform as well.

I will do my best to keep everyone updated on the status of these kits as I do realize that there is a fair amount of interest.

On a closing note, I would like any further discussion regarding bias to be part of a separate thread so that we can keep this thread on the topic of availability of the StopTech four wheel BBKs for the WRX and STi.

Thanks,
Tim Kelsch
www.stoptech.com

 

I have the front stoptech bbk with the anodized black finish. It is amazing the difference in handling this mod has provided. The new rear kit looks great, BUT?

Do we get charged additional for this finish?

Also, why is the pricing exactly the same for the front kit, given the more simplistic design as well as the lower level of duty on the unit?

Most other BBK companies charge less for their version of an integrated 4 wheel brake kit. Wilwood for example charges around 1300 for the front and 900 for the rear.

While I'm convinced I will buy this rear kit because I have the front kit, I just wonder if it is worth it given it is primarily for the look - based upon Stoptech's earlier testing of the original front BBK.

?

 

You will not be charged extra for the anodized finish, however do be sure to specify that you have the front BBK and you're looking for the anodized finish when you order.

The pricing for the rear kit is due to the fact that the ST-22 is a billet caliper which is inherently more costly to produce than a forged caliper like the ST-40 that's used in our front wheel BBK for the WRX. Other than that, a similar amount of material is used for the hat and bracket and it uses the same size rotor, the the cost of the two kits come out very close to each other. While you're right in saying that rear kits are generally cheaper than front kits, the fact that our four wheel kit is under 3.6K makes it an incredible value compared to technically inferior Brembo four wheel kit you can buy for just under four grand ($2494 front + $1435 rear = $3929).

If you're after pure performance, your money will likely be better spent on other upgrades. A couple very nice things about this kit are the smorgasbord of street and race friction options that are currently available in this pad shape and the increase in pedal feel that the kit will provide. Thanks for the bump by the way.

If you're looking for a rear kit, contact your local authorized StopTech reseller. They will be here sooner than you think.

To find out which vendors are authorized StopTech resellers, check here.

Thanks,
Tim Kelsch
www.stoptech.com

 

Tim, thanks for the info.

Yes I will be getting a kit this fall.