stevie1982

iTrader: (16)

Need some pointers

I have a P1 with the AP 6 pot front brake upgrade and i am looking to do some engine work in the new year and end up about 400bhp or there abouts, the suspension (struts, springs, alk, rear allot drop links, rear arb)and front brakes are done so i was thinking of getting the rear brakes upgraded before i run the extra power. with the current setup do you think this will be needed or am i going over board and trowing money away. i will be using the car for the road and the odd track day (unless i catch the bug)

what options do i have i have been searching page after page and have come up with very little

is it just a simple case of larger disks fitted along with better pads?

other than the BREMBO rear setup from a new age car but understand this can get costly due to having to replace the shoes and change the brakets

is there a bigger / better setup on the classic that i can replace the ones i have already?

i assume the standard rear brakes are single pots?

are ther e2pots of 4 pots that were fitted to the classic as standard or a classic upgrade option other than fitting newage?

or just a simple case of larger disks fitted along with better pads?

any help would be appreciated

thanks

bighead

iTrader: (1)

you can fit the 2001 upwards 2 pot calipers and disc(will need adapter brackets) that is the cheapest , next up is the brembo rear caliper and disc(will need brackets as well )
then there is the AP rear brake kits (the best ), but these cost well over £1200+ !!
value for money the 2pot rears will do , but for posing value ....APs (there is no subsitute )

stevie1982

iTrader: (16)

agree nothing better than seeing AP from under the rim but i am not wanting to spend that kind of money mate if i am honest.

i thought with the Brembo you need the bracket and there is something needed for the handbrake shoes to?

regards

Godspeed Brakes

iTrader: (259)

You need to fit the thicker handbrake shoes as well as fitting brackets to fit the rear Brembo's onto your P1 , see here

Classic Impreza 2 Pot & Brembo Rear Fitting Kits with Handbrake Modification

Cheers Ian

bighead

iTrader: (1)

yes , you will need thicker shoes/brackets and disc ( I have the rear brembos on my P1 ).
all the parts need can be obtain from Godspeed.
tbh ...the standard rear single caliper is fine
but when you modded everything else..............

ps ...there are some cheap brembos on the for sale section right now

Godspeed Brakes

iTrader: (259)

Just to add this kit is £175 in my group buy at the moment
Cheers Ian

stevie1982

iTrader: (16)

ok if they are fine, what size disks and what pads are good for an upgrade just as my current disks seem to have seen better days so may just replace them for bigger and better disks and pads if the current single pots are good enough

any opinions?

steve

Guinness

iTrader: (1)

We need a group buy on rear AP's i think.....

John 37

Why do you want to uprate the rear brakes?
The rears on Imprezas do so little work that overheating isn't an issue. Now if you've managed to increase the rear bias, that's a different matter but please tell me how you did it.

John

andrew jeffs

iTrader: (3)

The rear brakes do more work on a 4wd car,why do you think type rs had the 2 pot rear setup,they have the same power as the p1,must be there for a reason.I have the 2 pot and rear 290mm disk conversion on my late ppp classic,the disks cost me 100 quid,the callipers(beutifully made in aluminium from a type r)80 quid from ebay and rear bracket 50 quid from as performance,certainly adds to the overall stopping power,and looks much better...

John 37

The amount of braking effect that can be applied is in direct proportion to the weight on the wheels. The rear brakes are designed to do less work than the fronts to take weight transfer into account. That applies to any car unless it’s a 4x4 running a locked centre diff. The works Audi Quattro ran such a set up and was immune to F/R brake bias issues. The fact that a car is 4x4 doesn’t mean it runs more rear brake bias.
I don’t know the P1 setup in detail but don’t assume that things are fitted to cars just because they’re needed. There’s a lot of sales literature engineering in cars and Subaru are no exception. Why do Porsche (and Subaru) have their names cast into the brake callipers? It doesn’t make them work better but it looks good.
The standard Impreza brakes are over sized at the rear for the work they do. A measurement of brake temperature shows the fronts run a much higher temperature. The rears are largely limited by the rear brake control valve. Sure, changing rear callipers will give better braking but only if they’re designed to do that, ie bigger bore or operate on a larger pad radius.
The answer to Impreza rear brakes is to get them to do more work. That means altering the F/R brake bias. However, go too far and the car becomes unstable and could spin. That’s why manufacturers adopt such conservative settings, especially if they sell in the USA. Bigger brakes are needed at the front to dissipate the heat better. Since the rear brakes don’t suffer thermal problems, bigger brakes are not needed for that reason. If bigger rear brakes aid the balance, that’s another issue but balance can generally be improved by hydraulic means much more cheaply. Having said that, the design of Subaru’s system isn’t easy to change. I’ve heard that removing the rear brake control valve helps. Has anyone tried it?
I would dearly like to increase the rear bias on my MY2000 classic. It would improve so many aspects of the car. Adjustable bias would be ideal but I can’t see how to manage it without a hydraulic system revamp. Anyone?

John

The rookie

iTrader: (1)

Seconded....

Add in more front braking and gripier tyres and you transfer even more weight off the rear to the front!

Simon