I know reyland do the 300mm rear brake conversions using the original 4x4 rear caliper, but is there a cheaper way to do it?
the brackets look easy enough to make, i did my own on the front for the brembos so should be fine,
i dont want to go to the expense of rotors and bells all round, and dont see the point in doing the rears and not the fronts, so is there any solid disc alternative? what brakes to focus RS's use on the rear?
i believe the 4x4 caliper uses 20mm thick disks if thats any help.
Thanks
Graham

 

i used a set of st170 front discs on the rear of my 3dr, cant remember thickness tho

i was also using brembo 2 pot callipers, so not sure if they will fit the 4x4 calliper.

HTH mate

 

If you go onto Apec's website you can search OE fitments by diameter. It doesnt let you search by thickness though. So it's just a case of hunting.

There will be a lot of 300mm diameter discs to search through, and of course of various offsets, centre bores, stud patterns etc.
Drilling new holes isnt a big deal, but you will need a centre bore the same, or smaller than yours, as location is important. Fixing holes are not.

I just used Wilwood universal stuff for mine. Still wouldnt say it is overly cheap though. But it's not like you'll be changing them every year or so.

 

Is their any need to upgrade the rears? i've just bought a set of 4x4 rears to upgrade the 2wd items.

I have a decent set of AP's up front if that makes any difference

 

I wouldn't bother on a road car unless you've nothing else left to do. It just gives a little more stability

 

are they really needed mate??
don't forget its really easy to over brake the rear and end up swapping ends every time you go for the brakes!!!

would a decent set of uprated pads and discs be enough?

focus rs btw uses st170 rear setup. solid 270mm discs with single piston callipers the same as any rear disc focus but with a bigger braket to allow for the slightly bigger disc. probably not going to be upto the job on a cosworth though due to the focus being fwd.

 

I'd imagine most people do it for looks anyway.

And I think it'd take a bit more than that to encourage a Sierra or any similar car to swap ends under braking.

 

I had pretty much sorted doing the st170 front discs on the rear
made the mounts modded a caliper just needed to skim the disc back a bit and it would have beed done for about 60quid but then a proper 305mm kit came up cheap so didnt bother but it was all easy enough

 

i have a set of 300mm rear kit, Rotors bells and brackets, can anyone tell me where i can buy new disc rotors from . I Think they are brembo disc rotors, but came as a whole kit second hand.

 

Youd need to know disc width, diameter, number of mounting bolts and the PCD of those bolts.

then you can begin to search the various suppliers.

Or post a pic, and maybe they will be familiar to others.

 

I have fitted st170 front discs on the rear with mk4 escort xr3i front calipers. also fitted Hi spec handbrake spot calipers to make it motable. They don`t like hydraulic handbrake only systems it`s a fail.

 

i wanted to do it for performance mainly, looks are just a side benefit, i will look into the st170 option.
you might be right about not gaining much though, im upgrading to 4x4 rear brakes in the next few weeks so thought i may aswell buy 300mm discs instead of standard 4x4 at the same time.
Matt, did the caliper require much modifying? brackets easy enough? if you've still got the bits lying round PM me

 

I'm pretty sure I binned the brackets when we moved house but if I find them I will send them over mate ,I filed the caliper a little bit just to open them out a little only about 1.5mm but if you get the discs skimed back a bit then you shouldnt need to do that you will deffo need to skim the disc tho as its about 24mm new and iirc the 4x4 discs is 20mm ish but there plenty of meet on the ST disc

 

Are their calipers any good ? I emailed them about them a couple of years ago. No surprise I got no response.

 

I spoke to them at the autosport and got a good deal off them. They sent the calipers to me the next week and they are well made. They also were very helpfull on the phone when I ordered cables. Don`t expect the handbrake to be as good as an OE set up but they do make it legal. Plus if you put an hydraulic handbrake on it, mine will lock up with one finger operation well into 3 figure speeds!!!!

 

If there are any doubts about their ability to hold a car or for passing MOT, then I certainly will not be buying them