The Rookie

Its a cylinder (filled with a piston) in the caliper, its the pistons that drive the pad into the disc.

The stock caliper has 2 pots on one side and the caliper slides, the pots drive the pad into the disc and the caliper slides so the disc is clamped evenly between the pads.

A 4 pot caliper has 2 pistons each side, the caliper is fixed and the pistons all move to drive a pad into each side of the disc.

Simples!

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98 s-turbo now breaking for spares , now driving a BMW 320D M-sport

AP

I can confirm that it works 100% ok with the JDM rom file, I had an impreza ECU in mine after the std one got wet
It wouldn't work until JGM flashed on the rom files and reversed crank signal for the JDM rom..

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160bhp 4EAT Outback.....

mr_alkan

Thread Starter

..foz upgrade update..

uk wrx ecu went in without issue, several days in and all good. Turbo leak issue to sort though.

Brake question:- will classic impreza wrx front discs fit 99/00 forester?

cheers.

L

AP

Depends what callipers you sre using, if you are using the 2 pots then you will need the 277mm discs, if you are using 4 pots then you will need the 294mm discs.
Impreza and forester discs are the same thing..
Andy

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160bhp 4EAT Outback.....

Gigsy

Or SG Forester 2 pots (cheap) and 294mm discs

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Was MY03 FXT (262bhp) MY03 WRX (271bhp)
Now MY05 MCS, Z3 2.8, X3 3.0d, Vespa ET4 & BMW F700GS

fozzy-paul

I have 4 pots from a classic on my fozzy, difference in stopping power is night and day. probably your best bet cost wise, think godspeed are doing a special on discs and pads at the moment, then all you would need is some 4 pots.

mr_alkan

Thread Starter

..thanks for all the help people.

just to clarify though, 277mm discs fit, as do the bigger 294mm discs too?

many thanks.

steven

AP

Yes both fit without problems but you will need 277 with 2 pots and 294 with 4 pots

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160bhp 4EAT Outback.....

UKForester

My plan is to fit a brand new set of the Budweg WRX PRO subaru 4 pot copies with Godspeed disks and Kevlar pads.

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2001 Forester Turbo S & 440 bhp 2002 Impreza WRX

Brian Lacey

I did this change 11 yrs ago, one of the first things I did to the T/tb. Tried DS2500 pads on the smaller disk first...ok but not brilliant. Got larger disk and 4 pots + uprated pads (Pagid) ( All from Classic Impreza).. CDF brake stopper, braided lines etc . Car stops !
Tried cheap disks from ebay..Pagids ate them up. Better quality disks last much better.
Everything was a straight swop apart from moving upto 17" wheels to go over the brakes.
Well worth it.

Cheers

Brian

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1998 T/tb (indestructible !) & Ralliart Sportback.

Gigsy

..or SG Forester 2 pots - which are much cheaper off eBay and will give a big improvement over the stock 277mm discs and are more likely to fit under stock 16" rims

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Was MY03 FXT (262bhp) MY03 WRX (271bhp)
Now MY05 MCS, Z3 2.8, X3 3.0d, Vespa ET4 & BMW F700GS

Bassmaker

Just as a side note to this because the decision has been made already, the Forester calipers have a tendency to seizing or partial seizing, apparently. I fitted a set of 4 pots/294 discs, and they are a huge improvement but I discovered my front 2 pots were both seized on the front piston and not so free on the rear one. I rebuilt them with a full service kit but they are sitting in the shed now and have to be "re-free'd" every few weeks.

I went through a period around two years ago where one or other of the rears would partially seized while I was driving, often leaving me temporarily stranded. There are a few guys over here with Impreza track cars who are running the standard front brakes, with the appropriate pads I presume.

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Scruffy 99 S Turbo. TD04-19T hybrid. DeCat. JGM.

Brian Lacey

I had exactly the same problems with the T/tb brakes a few years back, continually getting stuck ! I solved the issue by fitting stainless steel pistons. I bought them from a chap on here whose father made them as a sideline. They fitted perfectly and no problems at all since then. Well worth the investment.

Cheers
Brian

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1998 T/tb (indestructible !) & Ralliart Sportback.

The Rookie

Mine never seized in 7 years......and I still have them for sale!

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98 s-turbo now breaking for spares , now driving a BMW 320D M-sport

joey_turbo

Had a sticky piston last night on the standard 2 pots.
It was fun watching a bright orange disc glowing. Not so fun thinking about the possible wheel bearing replacement.