can an st205 front caliper be narrowed?

[AE25]

just wandering if the parting face of the two sides of 4pot caliper can be shaved to narrow the caliper to suit a thinner disk? anyone got info to share?

[DeeCee]

possibly use a pad spacer. I know of examples in the UK where the st185 owners are retrofitting the st205 caliper to the 185 using a wrx 24mm disc and using an old pad without material behind the new pads. Not my prefered method, but an option?

[atmosports]

Yeap could be done but you'd want to make sure everything was machine dead true & square before bolting them up again, but probably easier to just ring racebrakes or the like & get them to make up a set of st205 pads with some more friction material on them to suit the narrower rotor or just buy some thicker rotors.

You could use pad spacers or a set of old backing plates but then I've generally ended up with problems using this approach which is probably why I've got a whole lot of sets of 1/2 worn pads here which really need a spacer behind them to wear down any further as it take too much pedal travel otherwise.

[Scottie]

but probably easier to just ring racebrakes or the like & get them to make up a set of st205 pads with some more friction material on them to suit the narrower rotor or just buy some thicker rotors.

might be possible to pop out the caliper pistons when the pads get low? You may know yourself to keep an eye on the pad thickness, but if the car is sold, one of the owners after you may get caught out....

[AE25]

might be possible to pop out the caliper pistons when the pads get low? You may know yourself to keep an eye on the pad thickness, but if the car is sold, one of the owners after you may get caught out....

my thoughts exactly.
so what issues do you get with a spacer behind a std thickness pad? squeel?
if i use these calipers i want to try get them to fit under 15" wheels which means dropping disk diameter down?? don't think i'll be able to fit 15's over the std 315x32 gt4 disk. so finding a smaller diameter with same thickness will be a problem.

[neo]

Lathe down the rotor.

its what I did to fit 2pot corolla caliper + rotor onto the corolla.

[Bazda]

On FWD rims with offsets from 30-40 they def will not fit a celica disc of 315mm.
You need to machine them down to 280mm to get brakes to fit in all 15" rims.

If your running RWD offset you can prob get away with skimming them down to 300mm.

But, the celica calipe/pad is designed to fit onto a 315mm disc, so if you machine it down I think the pads will run off the contact surface inner. If you look at a celica disc and put the caliper and pad on it you will get what I mean. They run a crazy wide surface contact area so I would be careful here.

[AE25]

cheers for the replies
is to fit an ae86 type strut in a ke25.. mounted to back of the hub rather than sitting on top. haven't had much luck finding a suitable disk to do this without major machining so was thinking to go along the lines of a race type floating disk on a custom hub for better options.
baz... you'd know a bit about this.. any idea if disk's hub have to be machined by a race brake person or is it up to the lvv certifier as to what is safe? im a toolmaker by trade so would like to make myself if possible.

32mm thick disk seems quite overkill for a car that barely weighs a tonne. would like to keep unsprung weight down. 275-280mm disks seem to be around the 25-28mm width which sounds good hence the caliper narrowing idea.
i'll definately check on that pad contact patch with smaller disk. if i really have to .. could trim the bad edges so it doesn't overhang?
would ideally build a system that uses unmodified parts. (disks/pads)
cheers

[Bazda]

cheers for the replies
is to fit an ae86 type strut in a ke25.. mounted to back of the hub rather than sitting on top. haven't had much luck finding a suitable disk to do this without major machining so was thinking to go along the lines of a race type floating disk on a custom hub for better options.
baz... you'd know a bit about this.. any idea if disk's hub have to be machined by a race brake person or is it up to the lvv certifier as to what is safe? im a toolmaker by trade so would like to make myself if possible.

32mm thick disk seems quite overkill for a car that barely weighs a tonne. would like to keep unsprung weight down. 275-280mm disks seem to be around the 25-28mm width which sounds good hence the caliper narrowing idea.
i'll definately check on that pad contact patch with smaller disk. if i really have to .. could trim the bad edges so it doesn't overhang?
would ideally build a system that uses unmodified parts. (disks/pads)
cheers

A 2 piece disc I have used, to make them work well they need to made full floating. So the hat taht you make can expand and not rip the disc apart where its bolted.
My first set were solidly bolted to the disc and it cracked around all the bolting point, so I had to get the guy who made them to make these tiny spaces that actually lift the hat off the disc XX thou so its actually a tiny bit loose.
Nice light discs at the end of the day but a hastle when you have to replace them disc as you need to CNC all the holes etc again.





There are plenty of disc out there which are around 280mm and 25-28mm thick. But its prob the off set you are after?
You want to get an offset where the adapters made are virtually just a piece of flat steel with holes only and no other machining on it I assume?

Also you might encounter the caliper hitting the inside hub as the calipers are wide just like the pads. From looking at the pic of ST205 front brakes I dont think you could go down to 280mm....unless you had a smaller hub...


On the wilwoods/AP etc they do it the other way around, long pad but not wide. Therefore it can fit basically every type of disc.

[79rolla]

to get disks to fit on the back just get some disks with the right offset and drill some holes for the bolts,

this it the setup i have for my ke, had them mounted on ke70 hubs and ae86 struts witch are all verry close to ke30, not sure about 25 tho..

http://i102.photobucket.com/albums/m109 ... G_2716.jpg

[RomanV]

Have a look for other cars which use the same wheel bearings, see if the shape of the hub is different.

For my front struts it ended up that townace front hubs gave heaps more space for a disc in between the hub and the strut. (This works for factory vented carina/corona/celica/soarer/cressida hubs, not AE86 stuff I dont think...)

I had a pretty good scour through the rotor catalogue at BNT for something good that would go on back of a hub while still being decent size and vented etc, front discs from a citreon xantia turbo are a rather odd design but perfect for that.