1st gen 4runner upgrade to T-100 calipers

[corax]

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
http://i280.photobucket.com/albums/kk171/batardsalamano/Brake%20upgrade/100_3555.jpg
you can actually see that the leading piston (one on bottom) is smaller than the other one - note the S12+8 casting mark. 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)
http://i280.photobucket.com/albums/kk171/batardsalamano/Brake%20upgrade/100_3554.jpg

Here's what happens if you try to use the T-100 (S13WB cast mark) calipers with the stock rotors.
http://i280.photobucket.com/albums/kk171/batardsalamano/Brake%20upgrade/100_3556.jpg
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
http://i280.photobucket.com/albums/kk171/batardsalamano/Brake%20upgrade/100_3563.jpg

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
http://i280.photobucket.com/albums/kk171/batardsalamano/Brake%20upgrade/100_3561.jpg

Finished product (kinda finished, I didn't have the rotors on yet in these pics)
http://i280.photobucket.com/albums/kk171/batardsalamano/Brake%20upgrade/100_3557.jpg
http://i280.photobucket.com/albums/kk171/batardsalamano/Brake%20upgrade/100_3559.jpg

for some other caliper options look here (http://www.ultimateyota.com/index.php?option=com_smf&Itemid=26&topic=6351.msg64036)
Here's the thread (http://www.ultimateyota.com/index.php?option=com_smf&Itemid=26&topic=6175.0) where I did the master cylinder upgrade

Here's what I found on Toyota caliper cast marks awhile ago:
TOYOTA TRUCK
8173/8174 95 ALL S12WE

4 Runner
8171/8172 95-91 ALL S13WB
8169/8170 91-88 ALL S12W R/L
4407/4408 87-84 ALL (4 Cyl) S12-8

Landcruiser
1478/1479 92-91 ALL S13WA
4407/4408 90-75 ALL S12-8

TOYOTA TRUCK
Pickup, Hi-Lux
8171/8172 95-91 T100 Pickup 4WD 1/2 Ton S13WB
2011/2012 95-89 2WD 4 Cyl. l 17S R/L
1242/1243 95-89 DRW AISIN 1 R/L
8567/8568 91-89 Long Bed F18Q R/L
514/515 91-8/83 2WD, 1/2 Ton AISIN
4407/4408 88-86 Long Bed 4WD W/4 Cyl. S12-8
4409/4410 85-80 Long Bed 4WD S12+8

*BTW* didn't get a chance to test them out yet as I ran into some caliper issues on the driver front (1st reman squirted fluid out of the seam where the 2 halves join together, second caliper was missing the brass o-ring that the brake line seals against, parts store didn't have any more so I have to go back tomorrow - but that's another story)

[CJM]

GL with it, arent you happy we discussed this at length before you tried it and found you needed the T100 rotors?

[DHC6twinotter]

Sweet! How different are the S12-8 calipers from the S12W?

[corax]

GL with it, arent you happy we discussed this at length before you tried it and found you needed the T100 rotors?


Actually, I was just gonna run with the stock rotors anyway for now (even with the overhang) and get slotted T-100 rotors in the very near future, but on the second trip back down to the parts store I had a WTH moment. Weird thing is, the brake pads still hang off the rotor, but only by 1/16" . . . I think that might just be something goofy with the brake pads though (T100 NAPA ceramic) because everything is T100 at this point - I'll just take the outer cicumference of the pad to the grinder to remove that bit



Sweet! How different are the S12-8 calipers from the S12W?


I'm not 100% sure, I know the S12+8 caliper has a small piston (leading edge) and a larger pistion where as I think the pistons in the S12W are all the same size as the larger piston from S12+8. Beyond that . . . . not sure

[CJM]

I would just run the stock rotors, its not a reace car and imho spending 300 bucks on a set of rotors that are drilled/slotted isnt worth it. Since the T100 rotors are thicker they will help dissipate heat better anyways.

[corax]

I would just run the stock rotors, its not a reace car and imho spending 300 bucks on a set of rotors that are drilled/slotted isnt worth it. Since the T100 rotors are thicker they will help dissipate heat better anyways.


I wouldn't do cross drilled and slotted anyway (overkill fueled by the ricer craze), just slotted - I found both slotted rotors for <$100 :D. That'll probably be down teh road anyway. 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.

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. 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.

[Obi..]

Why not just go the route I did and actually run a pressure readout on the rear lines and adjust the height of the LSPV rod to suit?

[CJM]

Honestly I keep asking everyone this Q and no one seems to go after it:

I had a lackluster pedal feel and didnt stop to well at all. I read the FSM and it said to adjust the rear shoes so they are 1-2mm away from the drum. If they arent that close then adjusting the LSPV is way to go, if that dont help then its time for a manual valve or a rear disc swap.

[corax]

Why not just go the route I did and actually run a pressure readout on the rear lines and adjust the height of the LSPV rod to suit?


The LPSV, as it is currently adjusted will bottom out 2"-3" before the suspension touches the bumpstop (then it just flexes the arm), so I don't think that's really the issue (though I could tie strap it to the floor boards) . . . I readjusted this afternoon and took it on another hot lap of the back roads, it felt about right as far as braking through a turn so I wouldn't want to go with much more rear bias because of wet weather handling.



Honestly I keep asking everyone this Q and no one seems to go after it:

I had a lackluster pedal feel and didnt stop to well at all. I read the FSM and it said to adjust the rear shoes so they are 1-2mm away from the drum. If they arent that close then adjusting the LSPV is way to go, if that dont help then its time for a manual valve or a rear disc swap.


That rear shoes are adjusted properly, very likely a bit tighter that 1-2mm. I'm also thinking of going with a stronger brake booster as I still have 1.5"-2" of brake pedal before I hit the floor (and that's really standing on it). The problem with running a dual diaphragm though is that they are 1" thicker and I really don't have the room between the booster and the intake manifold.
http://img178.imageshack.us/img178/3096/4r3fc4.jpg
I think I might run around a junkyard in the next week or two with a tape measure and try to find a single diaphragm with a larger diameter (more assist force) or maybe a dual diaphragm that I can "dent" to fit. That said, I think I should have gone with a 1" master cylinder instead of the 1 1/16" MC (though I do like the firmer pedal, I can't stand on it hard enough - I feel I should at least be able to bring it right to the brink of lock-up, right now it's now quite there yet) . . . live and learn.