Construction Zone
Don\
Welcome! Log In Register

Advanced

2008 SP STi brakes

Posted by sidewaez 
Cosworth
Paulinho Ferreira
Infallible Moderator
Location: Charlotte, NC
Join Date: 03/15/2007
Age: Midlife Crisis
Posts: 721

Rally Car:
Honda Civic



Re: 2008 SP STi brakes
May 12, 2014 10:24PM
Quote
sidewaez
Would a Performance Friction ZR34 caliper be a good choice, for the front of this car?
Yes those are probably the best calipers in the US rally scene right now. Its the same shit I have, and Derik Nelson in his M3.

As for the Clio R3T setup, guess who came up with that setup??? Yes its the same calipers front and rear that I installed in my Civic 3 years ago. The fronts are ZR34 which as said before are a late model roundy round caliper, and the rears are Formula 2000 calipers. The same setup I pushed into Ireland, Spain, France and Italy when I worked in Banbury.

But even though those calipers are better than the APs in the fact that they're forged monoblocks and have a few other built in features. The biggest problem is you're stuck with 1 or 2 flavors of pad choice. And because its PFC you're stuck with possibly never being able to get spare parts. I would recommend the AP calipers and they're a little cheaper, all pad manufacturers make that pad shape and the pads are super cheap.



Edited 1 time(s). Last edit at 05/12/2014 10:25PM by Cosworth.
Please Login or Register to post a reply
Attachments:
open | download - Fr brakes.jpg (32.7 KB)
Fr brakes.jpg
sidewaez
Blake Lind
Elite Moderator
Location: Hillsboro Oregon
Join Date: 06/09/2009
Age: Midlife Crisis
Posts: 233

Rally Car:
orange AE86


Re: 2008 SP STi brakes
May 13, 2014 02:20AM
Quote
Cosworth
Yes those are probably the best calipers in the US rally scene right now. Its the same shit I have, and Derik Nelson in his M3...

...I would recommend the AP calipers and they're a little cheaper, all pad manufacturers make that pad shape and the pads are super cheap.

I thought that's what was on Deriks's car.

Which AP Calipers? What size pistons front and rear? You said the pedal on your SP STi with GrpN brakes was crazy stiff what do you attribute that too, what m/c size is it?

Thanks!
Please Login or Register to post a reply
Cosworth
Paulinho Ferreira
Infallible Moderator
Location: Charlotte, NC
Join Date: 03/15/2007
Age: Midlife Crisis
Posts: 721

Rally Car:
Honda Civic



Re: 2008 SP STi brakes
May 13, 2014 09:02AM
Quote
sidewaez
Which AP Calipers? What size pistons front and rear? You said the pedal on your SP STi with GrpN brakes was crazy stiff what do you attribute that too, what m/c size is it?

Thanks!
The AP caliper I was recommending is the one everyone is using now the AP Racing CP8350. As for sizes I think there's only 2 sizes available, a "front" and a "rear" so not much fussing about that. Just setup the brake bias with m/c selection.

As for the GrN setup, it uses the OEM STI master cylinder, and no brake booster, so its horrible hydraulic ratio. The AP calipers have smaller pistons than the original Brembo calipers. To give you an idea just go drive a street STI without the brake booster connected and you'll see.

There's a few tricks GrN teams do to make things better like redrilling the clevis point closer to the fulcrum.
Please Login or Register to post a reply
john vanlandingham
John Vanlandingham
Infallible Moderator
Location: Ford Asylum, Sleezattle, WA
Join Date: 12/20/2005
Age: Fossilized
Posts: 14,152

Rally Car:
Saab 96 V4



Re: 2008 SP STi brakes
May 13, 2014 09:53AM
Quote
Cosworth

The AP caliper I was recommending is the one everyone is using now the AP Racing CP8350. As for sizes I think there's only 2 sizes available, a "front"

4 Piston - R2 or Similar Series - Ø38.1 / Ø41.3mm Bores - CP8350 aka 1.5" and 1.625"



and a "rear"
aka something with 4 x 1.25" aka 31.8mm


so not much fussing about that. Just setup the brake bias with m/c selection.

about the 8th-9th time this same thing has played out...somebody axs, I say "meh ---cars about that size use either 4 times blah blah or 2 times 1.5 two times blah blah"

, I get chided, corrected , lectured, and then the recommended caliper has MIRACULOUSLY, the exact size I said quite literally decades fawkin decades ago...

I try not to wonder WTF too much when people go to the trouble of correcting me and then after a few days end up recommending the exact thing down to the mm.

That's why I say its a fuckin miracle!





John Vanlandingham
Sleezattle, WA, USA

Vive le Prole-le-ralliat

www.rallyrace.net/jvab
CALL +1 206 431-9696
Remember! Pacific Standard Time
is 3 hours behind Eastern Standard Time.
Please Login or Register to post a reply
Cosworth
Paulinho Ferreira
Infallible Moderator
Location: Charlotte, NC
Join Date: 03/15/2007
Age: Midlife Crisis
Posts: 721

Rally Car:
Honda Civic



Re: 2008 SP STi brakes
May 13, 2014 10:04AM
Quote
john vanlandingham
, I get chided, corrected , lectured, and then the recommended caliper has MIRACULOUSLY, the exact size I said quite literally decades fawkin decades ago...

I try not to wonder WTF too much when people go to the trouble of correcting me and then after a few days end up recommending the exact thing down to the mm.
People correct you when you make silly statements that NASCAR sized caliper pistons are no good because "too touchy" and because some wankers in england like to use different sizes since way back when black jesus was born. When in fact piston sizes are just a small fraction of the equation. Thats the fuckin miracle ese. You dont need to rely just on caliper piston sizes.

And have you thought for a secong that the reason it has the same size is because its the same fuckin brand (AP)

comprende amigo?
Please Login or Register to post a reply
sidewaez
Blake Lind
Elite Moderator
Location: Hillsboro Oregon
Join Date: 06/09/2009
Age: Midlife Crisis
Posts: 233

Rally Car:
orange AE86


Re: 2008 SP STi brakes
May 13, 2014 11:02AM
Now that you make me think about it, in SP I'm free to change the master cylinder and I actually have a grn booster delete sitting on my desk but that makes me retain Subaru's weird bolt pattern master, how about something like this:

http://www.chasebays.com/product/subaru-wrxsti/chase-bays-brake-booster-eliminator

And then run a good proportioning valve to get the bias correct?
Please Login or Register to post a reply
Cosworth
Paulinho Ferreira
Infallible Moderator
Location: Charlotte, NC
Join Date: 03/15/2007
Age: Midlife Crisis
Posts: 721

Rally Car:
Honda Civic



Re: 2008 SP STi brakes
May 13, 2014 11:19AM
NO. That thing only uses one, single piston master cylinder. You need to have a tandem master cylinder. Its a cylinder with 2 pistons inside. One piston for 4 wheels makes things behave radical and god forbid you break a line. Also with a system like that your rear brakes will "bite" before the fronts.

Try and find an OEM suby master that is smaller diameter and call it a day.

I have the same GrN booster delete in mine.
Please Login or Register to post a reply
Attachments:
open | download - IMG_1778.jpg (59 KB)
IMG_1778.jpg
john vanlandingham
John Vanlandingham
Infallible Moderator
Location: Ford Asylum, Sleezattle, WA
Join Date: 12/20/2005
Age: Fossilized
Posts: 14,152

Rally Car:
Saab 96 V4



Re: 2008 SP STi brakes
May 13, 2014 12:23PM
Quote
Cosworth
Quote
john vanlandingham
, I get chided, corrected , lectured, and then the recommended caliper has MIRACULOUSLY, the exact size I said quite literally decades fawkin decades ago...

I try not to wonder WTF too much when people go to the trouble of correcting me and then after a few days end up recommending the exact thing down to the mm.
People correct you when you make silly statements that NASCAR sized caliper pistons are no good because "too touchy" and because some wankers in england like to use different sizes since way back when black jesus was born. When in fact piston sizes are just a small fraction of the equation. Thats the fuckin miracle ese. You dont need to rely just on caliper piston sizes.

And have you thought for a secong that the reason it has the same size is because its the same fuckin brand (AP)

Paul what the fuck--
I know, you know, we know
I knew, you knew, we knew

that there are a number of factors.
That's like saying the sky is blue today, the sky was blue 20 years ago.

And no I never thought it was the same brand---because I've seen AP Racing, Alcon, Brembo, Sumitomo all clustered around the same sizes for cars weighing whatever and doing the speeds we do on gravel... of course there's a whole slew of factors but I keep saying we would be foolish to ignore this information---especially when you keep recommending calipers that are in fact the size I've been telling people since the late 1980s...

And it's not because "some wankers in England" used anything one way or the other..
It's because we see this 1.5 + 1.625 front on all kinds of this from Audis in GpB days (Germen wankers?) to Volvos (Swedish wankers) to Opels (more Swedish wankers running the stuff---must have convinced the German wankers) to VWs--(damn, more Swede wankers fooling the gullible German wankers) to Subies (well we know there were a lot of British wankers involved with that---) to Misterbitchis (more English wankers)

So yeah maybe all the English works teams and all the Swedes works teams and all the Allemani werks teams are all wankers*....but those wankers all had enough budgets --just a weeeee bit more than clubbies here----to try out whatever they wanted for calipers with whatever sizes of pistons they wanted..

Somehow the sizes they all ended up with---for cars this size and weight on gravel surface---ended up pretty much the same...

Kinda like they could do any gearsets they wanted to homologate---and especially the overall box x final came out awfully damn similar---even once the FWD boxes went from stuff like old VW 5.08 final drive to the 4.2 (just to have bigger and stronger pinion) when you look at the 4th and 5th being under-driven, the overall 1 thru 5 remains more or less the same as other 2.0 cars FWD OR RWD

Kinda like valve sizes, cam profiles, pedal ratios, track width, overhang, a whole raft of things....
For a given size and weight car with a given size engine, a whole lot of things end up pretty much the same---if they are going to work well.

Basically what you and often Gene McC are saying is "There is no point to look at any details of what has ever worked and no point in doing comparisons,
no point at all in trying to learn anything,
no point in trying to see patterns, no point in trying to learn."

Pretty odd point of view if'n you ask me...





Quote

comprende amigo?

I think I do

*cannot comment on the French and Italian cars and teams because that's not where I have been armed with my vernier calipers and notepad. But I cna guess they are not particularly different.



John Vanlandingham
Sleezattle, WA, USA

Vive le Prole-le-ralliat

www.rallyrace.net/jvab
CALL +1 206 431-9696
Remember! Pacific Standard Time
is 3 hours behind Eastern Standard Time.
Please Login or Register to post a reply
john vanlandingham
John Vanlandingham
Infallible Moderator
Location: Ford Asylum, Sleezattle, WA
Join Date: 12/20/2005
Age: Fossilized
Posts: 14,152

Rally Car:
Saab 96 V4



Re: 2008 SP STi brakes
May 13, 2014 12:31PM
Quote
sidewaez
Now that you make me think about it, in SP I'm free to change the master cylinder and I actually have a grn booster delete sitting on my desk but that makes me retain Subaru's weird bolt pattern master, how about something like this:

http://www.chasebays.com/product/subaru-wrxsti/chase-bays-brake-booster-eliminator

And then run a good proportioning valve to get the bias correct?

OMG.

Blake what are you thinking?
That is bad.
Look at those clowns contact info.1300 bumfuck Blvd
Fucking Bummingham Alafuckingbammy

https://maps.google.com/maps?oe=utf-8&client=firefox-a&channel=sb&ie=UTF-8&layer=c&z=17&iwloc=A&sll=33.498157,-86.857766&cbp=13,263.6,0,0,0&cbll=33.498161,-86.857732&q=1300+Monroe+Ave+SW+Birmingham,+AL+35211&ei=6lVyU-L-Bo_hoASbl4HoCg&ved=0CCsQxB0wAA

Google Map and street view....
Hilarious what you find...



John Vanlandingham
Sleezattle, WA, USA

Vive le Prole-le-ralliat

www.rallyrace.net/jvab
CALL +1 206 431-9696
Remember! Pacific Standard Time
is 3 hours behind Eastern Standard Time.
Please Login or Register to post a reply
Cosworth
Paulinho Ferreira
Infallible Moderator
Location: Charlotte, NC
Join Date: 03/15/2007
Age: Midlife Crisis
Posts: 721

Rally Car:
Honda Civic



Re: 2008 SP STi brakes
May 13, 2014 01:22PM
Quote
john vanlandingham
And it's not because "some wankers in England" used anything one way or the other..
It's because we see this 1.5 + 1.625 front on all kinds of this from Audis in GpB days (Germen wankers?) to Volvos (Swedish wankers) to Opels (more Swedish wankers running the stuff---must have convinced the German wankers) to VWs--(damn, more Swede wankers fooling the gullible German wankers) to Subies (well we know there were a lot of British wankers involved with that---) to Misterbitchis (more English wankers)

So yeah maybe all the English works teams and all the Swedes works teams and all the Allemani werks teams are all wankers*...
John, I dont think you got it when I said wankers in England. Arent AP's from englang? Werent GrB Audi's on AP's? What calipers do the germans or sweeds make? None! And as I said before that continuity of sizes are because of the packaging. There's only so much space for pistons in multi piston calipers, so the practical size is around 38 to 45mm.

Bigger than that and the piston caps start to hit the bobbins (mounting hardware) of the disc to the bells. And smaller pistons require much more pressure and have a tendency to cause the pad backing plate to bend like a potato chip. These are the real reasons caliper pistons are sized like they are, not some prophecy that said, 1000kg car on garvel needs 38/41.

Lets stop this discussion, because at this point its not doing any good for people reading.


As for that Chasebays kit man, those guys started off doing wiring harnesses for engine swaps and wire tucks. Now they're in the brake business? Its like me and John opening a cup cake factory
Please Login or Register to post a reply
Andrew_Frick
Andrew Frick
Mega Moderator
Location: Greenville, SC
Join Date: 05/18/2007
Age: Midlife Crisis
Posts: 684

Rally Car:
Rally Spec Ford Focus


Re: 2008 SP STi brakes
May 13, 2014 02:56PM
Quote
Cosworth
As for that Chasebays kit man, those guys started off doing wiring harnesses for engine swaps and wire tucks. Now they're in the brake business?

So looking at their kit it looks like it was designed by someone who was more interested in eliminating the unsightly brake booster / master cylinder than a racing component. Much closer to wire tuck / shaved bay. Than a racing part.
Please Login or Register to post a reply
sidewaez
Blake Lind
Elite Moderator
Location: Hillsboro Oregon
Join Date: 06/09/2009
Age: Midlife Crisis
Posts: 233

Rally Car:
orange AE86


Re: 2008 SP STi brakes
May 13, 2014 08:57PM
Quote
Cosworth
NO. That thing only uses one, single piston master cylinder. You need to have a tandem master cylinder. Its a cylinder with 2 pistons inside. One piston for 4 wheels makes things behave radical and god forbid you break a line. Also with a system like that your rear brakes will "bite" before the fronts.

Try and find an OEM suby master that is smaller diameter and call it a day.

I have the same GrN booster delete in mine.

Good info, this is why I'm asking questions here because honestly I didn't know, the smallest master from any 1990+ suabru is 15/16" in fact the previous generation STi had 1.0625" masters.

What year STi is your's, what size is the master in it?

Quote
john vanlandingham
OMG.

Blake what are you thinking?
That is bad.
Look at those clowns contact info.1300 bumfuck Blvd
Fucking Bummingham Alafuckingbammy

https://maps.google.com/maps?oe=utf-8&client=firefox-a&channel=sb&ie=UTF-8&layer=c&z=17&iwloc=A&sll=33.498157,-86.857766&cbp=13,263.6,0,0,0&cbll=33.498161,-86.857732&q=1300+Monroe+Ave+SW+Birmingham,+AL+35211&ei=6lVyU-L-Bo_hoASbl4HoCg&ved=0CCsQxB0wAA

Google Map and street view....
Hilarious what you find...

That's pretty funny!



Edited 1 time(s). Last edit at 05/13/2014 09:00PM by sidewaez.
Please Login or Register to post a reply
Cosworth
Paulinho Ferreira
Infallible Moderator
Location: Charlotte, NC
Join Date: 03/15/2007
Age: Midlife Crisis
Posts: 721

Rally Car:
Honda Civic



Re: 2008 SP STi brakes
May 14, 2014 07:22PM
Quote
sidewaez
What year STi is your's, what size is the master in it?
06 and its OEM master 1-1/16". Car ran in GrN in the past so it has a bunch of OE parts that dont need to be for SP. So I'm thinking of finding a 7/8 master from a Forester from what I'm told.

So an STI 1-1/16 master is 48% bigger in area than a 7/8's from the Forester: 572.6mm^2 vs 387mm^2. So as you guessed that equates to a potential 48% increase in brake torque (gotta account for line and caliper flex with extra pressure)

Shirley with this modification and redrilling the clevis point it will make the brakes more like a race-cah. But based on my calcs, it will still be less tq output for the same pedal force.
Please Login or Register to post a reply
Do It Sidewayz
Chris Martin
Ultra Moderator
Location: Toronto, Ontario
Join Date: 01/15/2006
Age: Midlife Crisis
Posts: 567

Rally Car:
E-85 powered Impreza


Re: 2008 SP STi brakes
May 14, 2014 07:33PM
I'm using a Master cylinder from a Honda Civic, i THINK it's 13/16. I'm not running the booster (just replaced with a plate), but i believe it would have bolted up to the OEM booster as the bolt pattern was the same.

You will need to mess with the brake lines, but that's not a huge deal. It had 2 ports.

Trying to remember now, and i'm feeling like sticking my head under the dash. But i did drill a new pivot point in the pedal, but believe after trying it i'm back to the OEM hole.

Car brakes just fine with good pads, and pedal effort is "normal"



Chris
Please Login or Register to post a reply
sidewaez
Blake Lind
Elite Moderator
Location: Hillsboro Oregon
Join Date: 06/09/2009
Age: Midlife Crisis
Posts: 233

Rally Car:
orange AE86


Re: 2008 SP STi brakes
May 14, 2014 08:12PM
the 2008 and newer STi's have different bolt pattern for the master cylinder, but the booster bolt pattern is the same so I could just get a master delete for and earlier one, I looked through almost every year forester rockauto and couldn't find one with a master that was smaller than 15/16" anybody know what year it needs to be from?
Please Login or Register to post a reply
Sorry, only registered users may post in this forum.

Click here to login