Machining Brake Calipers

[WDE_BDY]

Just working on another brake upgrade option for my KE70 ute, unfortunately will require machining of the calipers. Thought I better get some more informed opinions before I pull out the grinder.
Calipers are Altezza RS200 2 pots with matching 296 x 32mm discs, trying to squeeze under 15" Speedstar RS-8's. The ridges on the caliper are just rubbing on the outer diameter of the rim.















Now, does it look like an option to machine around 7 to 10mm off those ridges? Doesn't look like too much of a problem to me, given the 4 large bolts holding the area together. Any feedback would be appreciated.

Callum

[crowncustom]

There shouldn't be any problems with doing it as long as it doesn't interfere with any of the delivery ports on the caliper.
I did this many years ago with the twin spot Sumitomos on a RT 104 Corona when I put
13"mags on it and it never caused any problems.
So my answer is yes go for it but thats my opinion
Cheers Brett.

[byteme]

should be ok *crosses finngers* BUT you also have to realize that those ridges wernt placed there for no reason. It's to strengthen the caliper and stop the whole caliper from flexing. flexing causes deflection which makes your pads work funny (think of only pushing on side of your brake pad in instead of the whole thing).

[EldarO]

i dont think it'll be that severe ezra.

back OT, take the caliper apart and check if its going to intefere before you start grinding anything.

im assuming those bolts are the ones holding the caliper together, and not the mounting bolts for the caliper?

Elmo.

[byteme]

yeah, but.....bah i went and bought wilwood sl-6 calipers because i dont want to bother with these crap brakes on my supra

[EldarO]

why does everyone say supra brakes are shit?

jump in my car man, you'll love it so much, you'll kiss the windshield.

Elmo.

[WDE_BDY]

Yeah, no fluid in that area at all. The more I look at them the more I think about machining down the rotors, only a road car so don't think they would flex massively but might pay not to take the risk. Means any replacement rotors would need to be machined but doubt I'll wear them out too quick.

Callum

[oldcorollas]

the bolts hold the two halves together.
the ridges provide the stiffness at the interface between the two halves.
if, for example, you have the thickness of metal fromt he bolt hole to the edge, you are halving the calipers resistance to bending at that point.

if you had a spare, you could cut one down and then test the flex with high line pressure...

i wouldn't recommend taking the ridges off.. but i like stopping
then again, if the car is light and you never want to brake at the calipers full capacity, then maybe you could do it.

can you machine the discs down 10mm and mount the calipers further in?

[WDE_BDY]

Thats what I will probably do, I should only need to take around 5-8mm of the radius so will cut disc down to just on 280mm diameter. Was hoping to keep a standard disc but it won't be huge mileage vehicle anyway.

Callum

[Big T]

New rims not a possibility? I went through this same dilema trying to find something to clear the brembos. I eventually had to slightly machine new rims to make them fit.

Eddie.

[WDE_BDY]

Nah, running 15's and really want to stay with them. Suit the car nicely.

Callum

[camry-GT4]

Im not sure if this suggestion will work, but what if you only took off only 4mm from the callipers and put on 3mm spacers so the rims sit further out? This should allow the clearance you require. Im guessing this way you wont screw up the strength of the callipers too much and you can keep your existing rims.
Good luck!

[Moppitt]

As you say, taking the rotors down a few mm and mounting the calipers further in is a much better idea than grinding material off the caliper. As was said above the metal in that area is likely to be providing stiffness in the body of the cliper, os grinding that area off may allow more flex.

More caliper flex may (among other things mentioned here) give you a longer brake pedal (due to more pistom movement relative to the caliper)as well as the possibility of uneven pad pressure giving overheating in some areas of the pad and uneven pad wear problems as well as the risk of catastrophic failure of the caliper.

[IN 05 NT]

10MM....that is a shitload to be taking off a caliper!!!!.... and i dont think an engineer would aprove!

if its only a few mm....say 3-4 then id say it would be ok.....

if you have a spare caliper, go get grinding and see what happens, but i think that 10mm is way to much to be taking off your brakes,

how about maching down the rotor to make it a 290mm and remount the caliper in tighter to the hub?

goodluck, blake

[ReQuieM]

Yeah I'm not sure about your local road-traffic authority, but redrilling/machining/grinding the caliper is a big no-no with vic roads.