Got my T-100 calipers on today. I already changed out the master cylinder, so I don't know how the brake pedal would feel with the bigger calipers and stock master cylinder. Here's the rundown:
Here are the original calipers, note the S12+8 casting mark in the second pic. Toyota uses standard calipers on several different models, the cast mark identifies which ones are identical (no difference in the cast mark to indicate left or right side though)
Here's what happens if you try to use the T-100 (S13WB cast mark) calipers with the stock rotors.
BTW, when I was getting parts I told the parts guy it was a '95 T-100 4wd.
So I got a pair of T-100 rotors to go with the new calipers and pads - the only thing that needs to change for the rotors is to push the bottom of the backing plate away from the rotors about 1/8" to keep it from rubbing - otherwise everything just bolts on
Here are the '88 4runner rotor specs:
# of Bolt Holes:6
Bolt Circle Diameter:5"
Diameter:11.375"
Height:2.535"
Maximum Lateral Runout:.004"
Thickness When New:.79"
Discard Thickness:.709"
Vented / Solid:Vented
Center Hole Diameter:3.942"
here are the T-100 rotor specs:
# of Bolt Holes:6
Bolt Circle Diameter:5"
Diameter:11.41"
Height:2.59"
Maximum Lateral Runout:.004"
Thickness When New:.985"
Discard Thickness:.905"
Vented / Solid:Vented
Center Hole Diameter:3.942"
So the only real difference is thickness and overall diameter - if you saw the "height" is also different, that's only because the rotor is thicker and the height needed to change to keep the rotor centered in the caliper.
The calipers are a simple bolt on affair, the only thing necessary is little bit of trimming to the backing plate
Finished product (kinda finished, I didn't have the rotors on yet in these pics)
for some other caliper options
look here
Here's the thread where I did the master cylinder upgrade
*edit*
Got it rolling this afternoon and burnished the pads/rotors nicely on some back roads . . . it's an improvement, but I think I need to go after the rear brakes now. The pedal feel with the bigger calipers is better, before with the stock S12+8 calipers and the 1 1/16" MC the pedal was rock solid. It's just not stopping the way I want it to and I have my doubts about the rear LSPV (I did move the rod up when I did my lift). I may have to spend $30 on a manual proportioning valve and ditch the LSPV in the near future - here's why: I got back from my hell ride breaking in the new pads, the fronts were definately toasty with some very slight discoloration on the fringes of the rotor (i.e. not in the swept area of the rotor) and the rear drums were only luke-warm, my coffee from this morning was still hotter than the rear drums. I know the rear drums don't get smokin' hot, but they should have been a bit warmer than that.