Brembo swap question

[GusGus91]

So I'm doing the my Brembo swap here within the next couple weeks.. And I heard I can't use the stock rear rotors on the STI, and put them on my Wrx because of a fitment issue, and something to do with the e-brake? If you could, elaborate on this or tell me what I need. I was unaware of this..

-Austin

[sperry]

The rear sti brakes are meant to fit on a car with an r180 rear diff instead of the smaller r160 that the wrx has. This means the backing plates and rotors are all designed around a larger rear bearing. The ebrake on the sti is larger in order for it to clear the larger rear hub.

There are ways to shim the wrx ebrake to mate to the large diameter rotor, but I believe they assume you're also converting to the 5x114.3 hubs. I don't know that it's possible to get 5x100 rotors that mate to sti brembos without drilling them yourself.

To be frank the right way to convert to the sti rears is to replace the rear diff and everything down the line, including the spindles and hubs and going to 5x114.3. Which is insane when you consider the brembo rears are really no better than the fhi 2-pot rears from the '06/'07 wrx. Furthermore, I would suggest StopTech brakes up front over the sti brembos as well. The brembos are good brakes, but there's a reason why sti owners drop them for StopTechs or for the race brembos. Unless you're getting a killer deal on the sti brembos and you're already switching to sti knuckles/hubs on all 4 corners, I think you can get better brakes for cheaper by smartly upgrading just the front brakes. People that do the sti brembos up front only end up thinking they need the rears because their bias gets all screwed up not because the 2-pot wrx rears suck. The right front bbk designed to match the 2-pot rears works very well. Ask the folks that are running that setup (Im one of them... on both the race car and he svx).

[GusGus91]

Thanks for the reply scott. I got the brembos off a 04sti, and i actually did get a good deal, that's why i got them haha. I think I may have found a solution? I dont know. Correct me on the link if im wrong there. Im still learning haha

http://www.fastwrx.com/dbastiadro.html

[sperry]

Yeah, that looks like it should address the ebrake issue. I'm not sure what happens with the backing plates though. Those rotors will be larger than the dust shields/backing plates that are already on your car. I'm guessing youre planning on cutting the shields down? Or is there a way to convert to the sti backing plate without having the larger hub?

Do you already have the brakes? If not I would still consider something other than the brembos because I think you can get better overall performance while keeping the much cheaper to maintain stock rears. Unless you really want brembos specifically... in which case the sti setup is probably the easiest way to go. You'll just be hurting if they stop making those conversion rotors.

[GusGus91]

Originally Posted by sperry

Yeah, that looks like it should address the ebrake issue. I'm not sure what happens with the backing plates though. Those rotors will be larger than the dust shields/backing plates that are already on your car. I'm guessing youre planning on cutting the shields down? Or is there a way to convert to the sti backing plate without having the larger hub?

Do you already have the brakes? If not I would still consider something other than the brembos because I think you can get better overall performance while keeping the much cheaper to maintain stock rears. Unless you really want brembos specifically... in which case the sti setup is probably the easiest way to go. You'll just be hurting if they stop making those conversion rotors.

Yea I already have all 4 brakes. It was just the cheapest route for me to get better braking. I got them pretty cheap. I figure after I sell my old ones I will have only paid 100-150 out of pocket for the upgrade for the calipers atleast. As far as the shields, I'm not really sure I haven't thought about that yet. I found a thread on nasioc, that kind of explains a few things. But I just started reading it. Here's the link for anybody that would like to look at it, or in case anybody else tries to do this in the future.

http://forums.nasioc.com/forums/show...74&postcount=1

[08awsti]

Ill do some research for you gus, because theres a company that has the rotors for the rear that keeps the wrx ebrake, with the brembo caliper.

[cody]

They're super expensive though.

[sperry]

Originally Posted by 08awsti

Ill do some research for you gus, because theres a company that has the rotors for the rear that keeps the wrx ebrake, with the brembo caliper.

Yeah, he posted a link to them in reply #3.

[ryan4601]

I did the fastwrx.com rear brembo upgrade on my 04 wrx. The kit allows for you to have the 319mm vented rear rotor size which is larger than the 290mm vented rear from the 06/07 wrx. It is a straight swap once you get the kit and have the calipers and pads. Rear backing plates will need to go, but a drill will handle that. Parking brake will work fine with the rotors. If you have stainless steel brake lines in the rear those will work fine with the brembos, but I would recommend getting new copper washers for the banjo bolt. Only other thing to watch out for is depending on your year wrx, your master cylinder bore size may be too small. When I say "too small" it doesn't mean that it won't work, but it may not be optimal. From what I read, pedal feel with the smaller master cylinder is not good with the brembos. If i remember correctly certain year wrxs (06-current? don't quote me on that) have a 1" MC bore while the 02-05 has the 1 1/16 MC bore which is the same as the sti. You can check you MC bore size by using a small mirror and taking a look under the MC in your engine bay. Let me know if you have any further questions.
Ryan

[GusGus91]

Originally Posted by ryan4601

I did the fastwrx.com rear brembo upgrade on my 04 wrx. The kit allows for you to have the 319mm vented rear rotor size which is larger than the 290mm vented rear from the 06/07 wrx. It is a straight swap once you get the kit and have the calipers and pads. Rear backing plates will need to go, but a drill will handle that. Parking brake will work fine with the rotors. If you have stainless steel brake lines in the rear those will work fine with the brembos, but I would recommend getting new copper washers for the banjo bolt. Only other thing to watch out for is depending on your year wrx, your master cylinder bore size may be too small. When I say "too small" it doesn't mean that it won't work, but it may not be optimal. From what I read, pedal feel with the smaller master cylinder is not good with the brembos. If i remember correctly certain year wrxs (06-current? don't quote me on that) have a 1" MC bore while the 02-05 has the 1 1/16 MC bore which is the same as the sti. You can check you MC bore size by using a small mirror and taking a look under the MC in your engine bay. Let me know if you have any further questions.
Ryan

Ok thank you for the info Ryan. I'll for sure let you know if I have anymore once the time comes..

[ryan4601]

Scratch my whole post, I wrote one up talking about how you need the bracket also, but if you have a 06 you don't need the bracket because your backing plate is correct for the brembo calipers. And the backing plate doesn't need to go, just the dust shields off the backing plate.
Ryan

PS: it is a 316mm rotor not 319 my bad

[GusGus91]

So since I have an 06 I just need to get the special rotor and just install it on the car and call it good?

[sperry]

Originally Posted by GusGus91

So since I have an 06 I just need to get the special rotor and just install it on the car and call it good?

That's what it sounds like. I'm just not 100% sure about what Ryan said about just removing the dust shield off the backing plate. I thought the dust shield and backing plate were one piece of metal... at least they are on the '04/'05 STi rears... which is why I think to do this conversion you either need the actual STi backing plates, or you need to cut up the WRX backing plates so the larger rotor will clear.

But again, I don't know much about what the '06/'07 brakes look like. All I know is I'm running the 2-pot rears with STi backing plates and the integrated dust shield is much larger than the WRX sized rotor I have on there.

[ryan4601]

At least on my car the dust shields were attached to the backing plate using spot welds (6 or 7 each if i remember correctly). You can use a drill and large bit to drill those out and the dust shields should come off. I am not sure about the 06 though, but I assume that they have to be pretty similar and looking at them directly will confirm it one way or another. If it is one piece, I'm pretty sure you could just bend the dust shiels back to allow for the rotor to fit.

To be honest on the 06 this swap should be much easier than on my car because your rear rotors are already vented and larger than my 266mm non vented crappy rotor. Because of this the dust shield may just need to be bent back a little to accommodate the larger rotor. On my car I probably could have just bent them back, but removal was pretty easy so I went that route. Plus your backing plate allows for the brembo rear caliper to be mounted without an adapter.

To answer your question, yes once you get the conversion rotor it will be a straight swap. The dust shield issue is not really a big deal, bending, removal either way will work just fine I think.
Ryan

PS: Scott, replacing the entire backing plate/dust shield with the sti (04) one is an option, but this conversion rotor allows for the parking brake to work without doing all of that. From what I understand DBA came out with this rotor relatively recently which has made swapping to bembos on the wrx very similar in cost to swapping to the 06/07 2 pot rear calipers. When I crunched the numbers before I bought everything it came out to about $100 more for the brembo swap. Really the only difference is the larger rotor diameter (316mm vs 290mm) if you complete the brembo swap.

[ryan4601]

Just to give you an idea of my experience, I purchased the rear brembos used off NASIOC, full conversion kit (DBA 4000 rotors, adapter brackets and bolts) from fastwrx.com and I also purchased a brembo rebuild kit from fastwrx.com as well.

The brembos were in working order, but I figured replacing the seals and dust boots would be a good idea. This was pretty easy and took maybe an hour tops to pop the pistons out, remove the old dust boots and inner seals and replace them with new ones. After that I pained the calipers black with a caliper paint kit (from Summit Racing I forget the exact name) to match my stoptech front calipers.

Total install time was probably about 2 hours. Remove wheel and remove the old caliper. Remember to use a zip tie or something to keep the brake line elevated because it will leak brake fluid on your garage if you don't. Fluid will leak anyway but this keeps it to a "minimum." Remove old rotors using the the bolt holes on the rotor and a rubber mallet. Sand down the surface where the new rotor will sit on the hub. I used 400 grit wet dry sand paper and some wd40. It doesn't need to be shiny new, but as little rust as possible is your goal. On my car I removed the dust shields using a drill and large bit, but you may just want to use a mallet or your hands to bend them back. Use the new rotor as a reference to make sure there is enough clearance all around. Once this is done, prep your new rotors by cleaning the braking surface (silver part) with brake clean to remove any residue. Then install the rotor onto the hub. Install the calipers and pads next, caliper first then pads once you have the caliper secured. Reinstall brake line with new copper washers, make sure everything is torqued down and then bleed the entire system.

Put your wheels back on and head out to bed your brake pads with whatever procedure you feel is best.
Ryan