subaru caddy ats brake swap "BBK"

[sickmint79]

this seems a popular brake swap to do and for all the wrong reasons. the reason is simply that you can make it fit.

based on this page $600 Brake retrofit, Cadillac ATS brembos, STI rotors. - Page 2 - Scion FR-S Forum | Subaru BRZ Forum | Toyota 86 GT 86 Forum | AS1 Forum - FT86CLUB
and this calculator Bias Calculator
and this article on bias White Paper - Brake Bias and Performance- Why Brake Balance Matters

i calculated the bias for the brz and for several BBKs available. defaults like pad height and some other stuff i didn't know were kept the same, just pistons and rotor sizes were varied. wilwood done with just front and front + rear setup as well results are in **percentage change in bias from oem** a negative number means more towards the rear, a positive number more towards the front. assuming it is already oem biased as far front as one might want, i would expect a BBK to shoot for changing the bias little or shifting it a bit to the rear. besides percentage deviation from oem to rear or front i also have the F:R ratio. the F:R chart here is for a different car (01 s4) but just using this to show how what seems like a small percentage can move things around a lot.

i would say based on this if you liked wilwoods, the way to go would be the wrx kit that fits the brz ($1105) or the full front and rear kit, because the 6 piston fronts alone shift the bias a lot. the only thing worse is the popular cadillac ats caliper swap. my understanding is you can fix this bias with a proportioning valve but i'm not sure how easy that fixing goes nor does anyone actually seem to install one. if you don't do one i do not see any value in this kit either. it is cheap and it fits, but there's a good chance it increased your braking distance both on and off the track. even as a looks only mod it fails in this regard, and seems to be barely cheaper than the wilwood.

tl;dr: if you have an 86, don't buy the ats brakes. get the wilwood 4r kit made for the wrx sold by ft86speedfactory. if you want more thermal capacity because you track it, then look at some other kits with larger rotors.

OEM: 0% deviation. F:R ratio of 2.3:1
wilwood 6-piston f(ront) + 4-p r(ear): -7.17% deviation. F:R ratio of 1.8:1
stoptech st40 4f: -0.86% deviation. F:R ratio of 2.2:1
wilwood wrx 4f: 0.14% deviation. F:R ratio of 2.3:1
z32 4f: 1.72% deviation. F:R ratio of 2.4:1
apr competition 4f: 2.58% deviation. F:R ratio of 2.5:1
wilwood 6f: 4.45% deviation. F:R ratio of 2.7:1
ats caliper 4f sti rotor: 5.88% deviation. F:R ratio of 2.8:1

Click to read more...

 

[Yaj Yak]

lots of words here

 

[OffshoreDrilling]

cliffs?

 

[Bob Kazamakis]

I remember people putting these on wrx's. People also used evo brembos because they were way cheaper than the Sti ones and you just needed a bracket.

 

[Rent Free]

cadillac ctsv and vette brake swap has been popular for w bodies amd f bodies for years.......

edit: graphs and charts only thing missing in this thread is pa pa pooolllllllls.

 

[Boostie]

Too many words but I love the brakes on my ATS

 

[sickmint79]

cliffs?

this is a swap of parts that fit, not parts that are right. it could be fixed but almost nobody seems to fix it on their install. not fixing it means the "cheap" BBK you installed in all likelihood increased your braking distance.

this is a risk with any BBK, but on the BRZ no other kit comes to making this problem as bad as the ATS swap. the $1100 wilwood kit comes with more stuff and is not that much more expensive. plus it doesn't have this bias problem.

is it worth doing on other cars? i bet it always ends up with this problem actually.

 

[Bob Kazamakis]

I think this could be fixed with a proportioning valve and/or a smaller master cylinder to increase line pressure.

 

[EmersonHart13]

People put CTSV brakes on GTOs all the time and they work very very well and are much cheaper than the big brake kits out there.

 

[sickmint79]

I think this could be fixed with a proportioning valve and/or a smaller master cylinder to increase line pressure.

it can be, although it seems like practically no one does it.

People put CTSV brakes on GTOs all the time and they work very very well and are much cheaper than the big brake kits out there.

well in what though? the car used to stop, and now the car also stops?

i have no idea bout the GTO, but people install these on the BRZ and say "they work great!" - but with any scientific test i'm sure they take longer to stop the car on the street. on the track i'm sure they do as well. it's not even worth it for looks if it does that, and this platform has a cheap kit without this problem anyway.

"upgrading" to perform more poorly isn't worth the cost, even if it is cheap. i suppose i say that while many of the same people will "upgrade" to heavy 18s and shitty all season rubber anyway though.

i mean this is the thought process of half of my peers:
- get heavy wheels that make brake / accel / turning worse
- get shitty rubber that make brake / accel / turning worse
- get shitty BBK that makes braking worse
- talk about how the car is still a bit too slow (weird) for them and how they will some day get a turbo

and i'm just like gdammit

 

[Bob Kazamakis]

Just because nobody on the internet says they use an adjustable proportioning valve doesn't mean nobody does it. It's very easy to install and very cheap parts.

 

[sickmint79]

people giving no fucks don't even seem to know or care about the problem. also seems some people seek out the cheapest pads to shove in there after install. painful

 

[Bob Kazamakis]

Other than "cool story" I don't know what else to say here.


Welcome to every car type group ever.

 

[raresvt]

Guy I work with just did this swap in his wrx..

 

[raresvt]

 

[EmersonHart13]

This guy races his

The Ultimate CTS-v Brake Thread - LS1GTO.com Forums

Seems serious about racing too: "'12-'13 ScrScca SM Champ"

All he was trying to do was decrease fade.

 

[Rent Free]

superiority complex be like ZOMG im gonna fit caddy brakes on my BRZ itll be soooooo badass much cool.......... look at my pretty charts everyone.....

welcome to 2004 lol drinkie aka dave put ctsv brakes on a wbody like a decade ago.

and people have been doing it for a long time in the sti crowd. why? well gee the frs/brz share alot of parts weird. :thinking: you dont say......



http://www.grandprixforums.net/threads/39174-The-Big-Bad-Brake-Thread

specs and part numbers for ctsv and vette calipers in there. alot of the oem brembos are the same just different colored.

so in theory here if ctsv ones fit the mounting tabs and gm offered massive carbon brakes on the zr1 vette just go full retard and put them on

 

[sickmint79]

This guy races his

The Ultimate CTS-v Brake Thread - LS1GTO.com Forums

Seems serious about racing too: "'12-'13 ScrScca SM Champ"

All he was trying to do was decrease fade.

it may be a better fit from the get go ie. the ats and gto are certainly closer than an ats and brz. i was going to try and calc stuff but i couldn't find any numbers and got lazy. plus if he is out there racing i would suspect he'd take the opportunity to fix the bias. they certainly have better thermal capacity than oem stuff, although the problem on say an unfixed brz is that you're also probably generating more heat as well since you have to be on them longer to slow you down to where you want to be, cuz the braking distance increased.

superiority complex be like ZOMG im gonna fit caddy brakes on my BRZ itll be soooooo badass much cool.......... look at my pretty charts everyone.....

welcome to 2004 lol drinkie aka dave put ctsv brakes on a wbody like a decade ago.

and people have been doing it for a long time in the sti crowd. why? well gee the frs/brz share alot of parts weird. :thinking: you dont say......



The Big Bad Brake Thread

specs and part numbers for ctsv and vette calipers in there. alot of the oem brembos are the same just different colored.

so in theory here if ctsv ones fit the mounting tabs and gm offered massive carbon brakes on the zr1 vette just go full retard and put them on

out of curiosity i viewed this post to re-affirm my belief that you are unable to add any value to a conversation ever. no surprise to find some silly attempt at childish quips and then apparently completely missing the point about the post entirely.

 

[Bob Kazamakis]

Your point doesn't take into account ways to actually make them work though. You're also posting this on a forum where I think there's one other brz but multiple people who have vehicles in which this is a usable swap.

 

[sickmint79]

Your point doesn't take into account ways to actually make them work though. You're also posting this on a forum where I think there's one other brz but multiple people who have vehicles in which this is a usable swap.

i mention the prop valve, although i've never used the thing so that's all i mention in regards to fixing it. really it is a c/p from some 86 facebook group posts that i made, and thought some people may find interest in due to the caliper being used in a lot of other platforms, and given that half the 86 people don't think (or knowingly don't care) about the bias.

maybe it is a perfectly usable swap from say gto oem to these, but people should minimally at least be aware it can/does change bias, and consider what they may need to do to fix it. this doesn't seem to be done much in the 86 community and i think it's questionable if it is by others like the wrx guys as well.

the kit that closest matches the brz in the above is actually the wilwood 4r, which is really a wrx kit. so my guess would be this pushes bias heavily frontwards on the wrx as well.

 

[Rent Free]

click the link and all the info on rotors and calipers and part numbers in there.........

looks like [MENTION=2449]ilikemtb999[/MENTION] is doing just fine in here......

 

[sickmint79]

click the link and all the info on rotors and calipers and part numbers in there.........

looks like [MENTION=2449]ilikemtb999[/MENTION] is doing just fine in here......

you are again, completely missing the point. this is completely irrelevant to any conversation above whatsoever.

what part number is noticeably actually missing, is any mention about bias or the prop valve to fix it. it is not listed on the brz/wrx sale page here:
Subaru and Scion 4 Piston ATS Caliper Big Brake Bracket Kit

nor is it part of the 20 minute install video here
https://www.youtube.com/watch?v=0Ofn9qgdFsU

 

[Bob Kazamakis]

And you're missing info like master cylinder sizes for each of these vehicles being discussed.



Also an adjustable proportioning valve is so simple you could probably install one. It goes between the master cylinder and the line to the rear of the car and you twist a knob. WOWWWWWW

 

[Rent Free]

this thread.....

 

[sickmint79]

And you're missing info like master cylinder sizes for each of these vehicles being discussed.



Also an adjustable proportioning valve is so simple you could probably install one. It goes between the master cylinder and the line to the rear of the car and you twist a knob. WOWWWWWW

great, so why is it completely ignored by the kit makers, the instructions, and the majority of people who install the kit? don't yell at me, i'm not the one who assembled it, i'm not the people who install it and ignore it either.