Umm, yes it does. If you know physics that small extra amount pushes the lever arm out and increases the torque applied under the same psi of pressure.

I mistakenly bought Sport Rotors and Calipers when it was time to replace due to stuck pistons. I guess having 17" wheels on an SR5 doesn't mean you have big brakes!

Anyway, rather then return the parts and order up the smaller parts, I found this thread and proceeded to upgrade my brakes. Yes, I had to bend the backing plate to clear the bigger rotors -- I hope to correct this issue with the bigger plates if I can find them.

My new thinking is that if you are running 17" wheels, and need new brake calipers & rotors, there is no reason not to go bigger and better.

Thanks for all the great information.

I know physics and I also know reality. I know there is such thing as a 1.0 earthquake on the Richter scale and a 2.0 is 1000 times stronger, but you won't feel either. The difference between the two rotors is miniscule and you are not going to notice the difference.

Actually, as long as we are splitting hairs here, the Richter scale is a base 10 logarithmic scale which means that a 2.0 is 10x as powerful as a 1.0. Additionally, if you guys really want to end the argument over bigger brakes all you have to do is look at the equation for torque, torque=(length of lever arm) x (Force applied)(Sin theta). Since the angle relative to the lever arm is perpendicular in both case you can ignore the Sin theta portion. This shows that changing the length of the lever arm to 338mm from 319mm will increase stopping power by 5.9%. (338/319)=1.0595. So, it certainly does increase stopping power. The question is, is it enough to worry about?

Did the SR5 V8's come with the larger brake set-up. I can't seem to find the identifying letters/numbers on my calipers.

Have to say; when when I need to stop it does it really well.

I have noticed that when I actuate the brakes suddenly (like when I've just noticed that I'm about to miss an exit), its like the computer decides that I need to stop really fast and does this brake assist thing; puts them right on the edge for maximum braking effect. Never experienced that before in any other vehicle.

It must be a big enough difference that Toyota designed bigger parts and used them, vs using the same brakes on all models. I'm sure in there bottom line there was a price difference.

The identifying characters will be on the back of the caliper. I think its mostly the sports that have them. I have the sport based urban runner package and it has them.

Yes. All Sports have them and you could pick it on the Limited Trim. My understanding is that no SR5 package had the option.

As for the enhanced stopping power. Meh? The brake pads (the all important part that does the actual stopping) is the same for all models. The calipers are different to accommodate larger rotor, but the pads are the same. So, the surface area is larger on the Sport rotors, which probably means enhanced heat diffusion. This means you can hold that aggressive stopping longer without doing any harm to the rotors, but in a jam; as in an emergency stopping situation, you should get the same response from them all.

At least that is how I see it. Without larger brake pads, which the sports do not have, I simply see the larger rotors as being more robust and allowing for a longer history of aggressive stopping. The actual X ability to grab the rotor is determined by the foot print of the pad. Unless the sport calipers are built differently (say, able to physically exert more force), my brain tells me that they should perform similar, but that aggressive stopping in the sr5 will lead to more rotor problems.

This is, of course, my take and not fact.

So how are those Fenco calipers doing i may eb doing this in the next couple weeks

The calipers are different also, I don't know if they apply any more or less force on the pads (which are the same between models as was stated) I would think though that the sport rotors offer more material for heat to dissipate through and offer slightly better thermal properties? It might not be much, but obviously enough for Toyota to put the money and effort to make new tooling, dies, and castings for a separate brake system.

sounds like an easy diy...am sorely tempted to try this out..about ordeing calipers and rotors from napa......seems the only big challenge is removing the back plate?....trimming it a lil should work, but wont it let in dust and other debris that it was supzd to keep out?

it appears the trimming isnt such a big deal.
see pics below.

4th Gen Brake Upgrade Glock_19 by Ducmonsta

My 2008 UrbanRunner has two tone leather/alcantara seats from the factory. Question is what rotors and calipers do I have. It has limited wheels with the Xreas suspension. I assume I have the sport model brakes, going to check now.

17 on the back of the calipers. I could barely make it out because of the rust. With 80k miles, probably wouldn't be a bad idea to replace the calipers as well.

Urban runners are based off of the sport model, we have the larger brakes.

Front rotor before throwing the tire on.



Rear

I have this nagging feeling that I forgot something. Gonna start bedding the brakes tmw morning.