Sudowoodo

iTrader: (1)

I posted this in the brakes and suspension section but no replies, so I'll try here. My old 2005 STi is now a parts car and I want to salvage its front and rear brakes and try to put them on my 86 GXL. Anyone know how difficult it would be to do so? I saw the thread were a guy put evo brakes on his rx7, but i was wondering how different it would be for STi brakes. Thanks!

sp0ngebob

iTrader: (1)

at a high level you need to fab up some kind of bracket/spacer to mount the calipers to the hub. you need to make sure that the pad face is compeltely on the rotor and that the back spacing of the caliper when loaded, is centered on the rotor. this is actually pretty common to do. you'll find that brakes arent all that specific once you start measuring. after that you'll have to machine a spacer out of something rather tough to get the proper alignment.

This assumes that the caliper, when centered to a rotor would clear whatever wheel you want to use.

If you are going to try and use the STI rotors too, make sure its worth it. while they might be larger the amount of surface area might be vastly different (better or worse).


Are the STI brakes any better than the turbo calipers? I have no idea what comes on that car.

Sudowoodo

iTrader: (1)

The rotors are much bigger and need 17" wheels to clear the brakes. Not sure on the specs but I'm pretty sure there's more surface area. I have turbo brakes on my rx7 already. My STi had great stopping power, and was a 3600# car compared to my 2700# rx7. The stopping power on my rx7 is pretty weak after driving my STi for a year. It doesn't seem too difficult to make them fit well though. Thanks!

1NSIGHT

iTrader: (3)

Too much work and not worth it. Get turbo 4 pots and good pads. I can lock up 255 tires at 40mph. thats more than enough power.

Sudowoodo

iTrader: (1)

I already have turbo 4 pots with good pads. And locking up wheels doesn't mean your brakes are good. You can lock up wheels with even the weakest brake setup.

Acesanugal

iTrader: (5)

You must realize that these braking systems are twenty plus years old.. compared to a modern sports car, they will not have quite the initial bite that overboosted systems has today. Get a bigger master, brace it against something, go stainless, and get slotted rotors. Should provide you with a more modern feel.

Personally I like the four pot system in stock form well enough. Good feel and modulation, and its like throwing a boat anchor out the window..

pfsantos

iTrader: (1)

Sudo...when you did the TII brakes, did you change to a TII MC and booster? That would a lot and people usually don't bother.

1NSIGHT

iTrader: (3)

A weak braking system wont be able to lock the wheels. Its literally the opposite of weak; having to overcome the inertia of the wheels and the friction coefficient of the tire.

Have you measured the relative stopping distance between both cars? The current stopping distance of your FC? Or does the car feel like its not stopping as well as the STI?

Sudowoodo

iTrader: (1)

The previous owner did the swap so I'm not sure if it has the turbo master cylinder. And I haven't compared stopping distances since my Subaru doesn't have a working motor in it, but it certainly feels like the brakes on my rx7 are no where near as strong as my STi's brakes were. I'll check and see what master cylinder it is and if its the stock one I'll probably try to get ahold of a turbo master cylinder. I didn't think that the master cylinder made that big of a difference. Thanks for letting me know!

sp0ngebob

iTrader: (1)

old braking systems have 0 to do with this.

cars still use floating calipers. those designs havent improved braking distances over 40 years. what changes that is the friction materials of the pads/rotors


bigger brakes doesnt mean better, and neither does newer in this case.


would be interesting to see but likely a pad swap to something like a carbotech and some better lighter rotors would be more worthwhile than all this fabbing.

Hiko

iTrader: (2)

Stopping distance really is mainly affected by tires. The only real benefits to a larger brake setup, assuming the stock setup is worth half a turd, is better heat management and feel. So by upgrading, your stopping distance wouldn't really change, but it'd be a lot more consistent (safe) at the track.

In short, if you aren't going to track the car, it's probably not worth the money to put STi brakes on your 7, unless you like the bling factor.

Sudowoodo

iTrader: (1)

Well I do plan to track the car. I'll probably go ahead and try to get it to work.

pfsantos

iTrader: (1)

Well, pedal feel is also a big part of the equation when it comes to liking one's brakes.

** OP, if/when you look for the master, make sure you also get the booster with it. Very important. edit: and the vacuum hose going to it from the intake...some have a one-way check valve **