[corax]

so I was looking at my friend/roommate's spare small block modified circle track car (also has a go cart with a CBR929 engine ) and the front calipers caught my eye because they look oddly similar to the T100 calipers I got a little while ago.  I'm not planning on swapping to Wilwoods, but it'd be some good bling.


except these say WILWOOD on them

so I started taking some measurements
the 1" mark is at the center of the bolt in this picture, so the mounting hole spread is 3.5" - the same spread as my 1st gen and t-100 caliper (should be the same for the 1st and 2nd gen truck/4runners)

caliper height from the bolt centerline - just shy of 3"

caliper depth - the inside of the mounting ear is at the 1.5" mark - caliper centerline 1" past that - 5.25" total width


BTW, my roomy also said that Jaguar used the same 3.5" mount hole spread on a number of older cars, but with 6 piston cast iron calipers   The other standard mount hole spread for Wilwood is 5.25" center-center, and you can get either mount pattern in a variety of caliper piston sizes, up to 2" (the S12W caliper is ~1.75" piston diameter)

******************************************************
The T100 S13WB calipers (90's V6 caliper with matching piston diameters)

3.5" caliper mount hole spacing (excuse the skuz, I only bothered to clean and paint the part you'll be able to see once mounted )

caliper height from bolt centerline - just shy of 3"

caliper depth - the inside of the mounting ear is at the 1.5" mark - caliper centerline 1" past that - 5.25" total width

[corax]

yep, 4 piston fixed mount (non-floating) just like 1st and 2nd gen.  I'll also be sure to get piston diameter specs between the WilWood and my T100 calipers - if they are the same, then there's really no benefit anyway - besides bling factor

[corax]

SEE REVISION IN POST #1

So it looks like Wilwoods would be a direct swap - no adapters necessary.  The next step is to see if my roomy has a spare caliper that I can borrow to confirm / reject this notion.

On a side note, this is a testament to the O.E. Toyota equipment available.  While the Wilwoods can be had with a larger caliper piston diameter (higher apply force on the pads), it doesn't even have the cooling fins like the Toyota calipers do . . .

[slosurfer]

You'll have to forgive me for my brake dumbness. 

So is any of this an upgrade from what would be on a 93 v6 4runner?  Like I said, I have no clue about brake stuff.

[corax]

look at the first T100 caliper pic, the backside shot, if your calipers also have a cast in number "S12W", then it would be an upgrade only if you got a Wilwood caliper piston diameter over 1.75" (you should currently have 1.75" diameter pistons).

Say you have 1000psi generated by the master cylinder in teh brake hydraulic lines, if you have a caliper piston with 3 square inches of surface area (the flat round part), it would generate 3,000 pounds of applied force to the pads (1,000 psi x 3sq/in = 3,000 pounds force) -- now lets increase the piston diameter and thus the surface area of the piston to 5 square inches with the same MC pressure, 1,000psi x 5sq/in = 5,000 pounds of force on the pads.  This added force generates elevated levels of friction and, as long as you can generate enough traction, you slow down much faster.

BTW, 1.75" diameter piston (S12W) = 2.40 sq/in
2" diameter piston = 3.14 sq/in = 31% increase

Wilwoods can be bought in all different size piston diameters for different applications.  You also have to take brake bias, or the front / rear split, into account and adjust that accordingly (ditch the LPSV for a manual brake proportioning valve).  Also, the larger surface area means the MC piston should be sized larger to move the added fluid volume - - - there are alot of variables involved

[Cebby]

Aren't we talking about negligible benefits until you upsize the rotors?  I understand the whole additional force part of the equation, but won't that just generate more heat and warp rotors (unless a slotted and/or C/D rotor is used)?

[slosurfer]

Okay, I think I'm starting to understand now. Thanks for the lesson.  I just went and looked and mine are "S12W" "S13WB".  I feel better now.

So there still is no plug n play brake upgrade for us 2nd gen 4runners like the 3rd gens have with the tundra upgrade?

Edit: Due to Keith's later post, I went back and looked under the dust better and mine are "S13WB"

[corax]

Aren't we talking about negligible benefits until you upsize the rotors?  I understand the whole additional force part of the equation, but won't that just generate more heat and warp rotors (unless a slotted and/or C/D rotor is used)?

heat is a by-product of the friction being generated.  Think about it this way it takes energy to get moving and it takes energy to stop.  Where does the energy from motion go as you slow down and stop?  It is transfered to heat energy, so theoretically you wouldn't generate more heat, just the same amount of heat faster.  Also, heat doesn't warp rotors, uneven cooling does.  High iron content rotors (the type that rust after every car wash) are less prone to this.  Then there's also the false "warped" rotor syndrome, created by uneven brake pad material transfer to the rotor causing an uneven coefficient of friction as the rotor spins (slip-grip-slip-grip) -- Here's some more reading -> The "Warped" Brake Disc and Other Myths of the Braking System

Also, the main point of this isn't to suggest an "everybody" type mod - unless you want the bling of having Wilwood calipers (get the 1.75" pistons and just bolt them on, the only improvement would be weight savings and better heat disipation through the caliper itself) - but to illustrate how robust the stock equipment is.  That said, improvement can be had with the bigger piston sizes available, but it's not a simple mod.

I would recommend this reading to anyone looking at brake upgrades -> Stop Tech Technical White Papers

[CJM]

The T100 not only has different calipers-it has a larger diameter master cylinder, its bigger than the LC!

http://www.pirate4x4.com/forum/showthread.php?t=251887

FWIW my t100 can stop on a dime, all I have are new calipers, performance hawk LTS pads and new rear shoes and wheel cylinders and drums.

[slosurfer]

CJM, that link shows that some of the T100's and the V6 4runner w/ ABS both have the same size (1 1/16") bore MC.

[CJM]

CJM, that link shows that some of the T100's and the V6 4runner w/ ABS both have the same size (1 1/16") bore MC.

I hadnt noticed that Chris, even so perhaps it has to do with the calipers?

One big thing I noticed was my pedal wasnt firm after I changed the whole system (calipers, rotors, pads, shoes, drums wheel cylinders) till I adjusted them more. I had initially adjusted and spun to check for freeplay, I figured a 1/2 to 3/4 of a full turn would suffice..

I then read in the FSM that the rears must be adjusted to 1-2mm of touching iirc. I choose to do it with a simple playing card I cut to fit in the inspection hold of the drum. If it cleared that I felt it was close enough and the pedal was SOOO much better.

[corax]

**Should we include the debate over steel rims versus alloy's as far as heat sink capabilities??

nah, but if you want to get technical, we could throw in rotor mounting and the resultant internal stresses generated by uneven lugnut torque on "non-captured" (able to remove without pulling the hub) rotors . . . 

[Tankota]

One advantage gained by using performance calipers it that they are usually made of aluminum not cast iron. Much better head dissipation and less unsprung weight. I'll bet that those Willdwoods are aluminum and that the T100 calipers are Iron.

Just the other day I helped a friend install Rotora brand perforce brakes on his Celica. Those Rotora calipers were huge but weighed about the same, if not less that the stock single piston calipers.

[corax]

 From http://www.kang-rim.com/brand/toyota.htm
 
ITEM NO.   YEAR   APPLICATION FOR   CASTING NO.
3219/3220   92-88       F18N R/L
3513/3514   92-88       54-18 2A / 2B
54-18 R AISIN  / 54-18 L AISIN

Camry
603/604   88-87   ALL   57-25 R/L
2015/2016   10/87-8/86   ALL   57-22 R/L
605/606   9/93-95   S/W W/4 Cyl.   35-10 R/L
605/606   95-88   Sedan   35-10 R/L
605/606   9/94-3/92   S/W   35-10 R/L
1431/1432   96-92   6Cyl   57-28 3 R / 57-28 4 L
8563/8564   96-92   4Cyl   57-28 1 / 57-28 2

Celica
1431/1432   95-94   ALL   57-28 3 R / 57-28 4 L
605/606   93-88   ST165 & ST185 4WD W/Turbo   35-10 R/L
603/604   93-88    ALL   57-25 R/L
2015/2016   91-90   ALL   57-22 R/L

Corolla, FX, FX16
3541/3542   97-93   ALL   54-22 3AR / 54-22 3BL
54-22 5401 R/L
1303/1304   92-89   ALL   51-18 NO.1 / 51-18 NO.2
1303/1304   88-87   FX16   51-18 NO.1 / 51-18 NO.2
1303/1304   88-83   FX16 FWD   51-135 C NO.1 / 51-135 D NO.2

Cressida
1236/1237   92-89   ALL   P12E R/L

Paseo
8561/8562   96   ALL   48-11 1702 R/L

Tercel
8561/8562   96-91   ALL   48-18 1702 R/L
803/804   90-86   ALL   48-11 M / 48-11 N

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

Previa
1584/1585   97-91       2403
1471/1475   96-91       2321 R/L
1710/1711   95-90       43-18 2G R / 43-18 2H L
1472/1473   95-91   W/o ABS   2318 R/L

Van
1032/1033   86       2306 R/L

[slosurfer]

I went and looked better through the dirt on mine and I do indeed have S13WB calipers.  I went back and edited my earlier post.

Now it only shows the T100 going to 95 but didn't it go past that?

Any info on the tacomas and tundras?