Big Brake Kit Discovery

[seth_man]

well i had some extra time at the shop and decided to try something out just for s&g's. i discovered that the AEM big brake kit for civics BOLTS ON to the yaris. NO Cutting, Drilling, Cursing or Modifying to bolt them on. 12" rotors and they fit under my 16" wheels. i did have to clearance the front top of my caliper .010" or so to have a little clearance for my stick on wheel weights.

What you will need:

1. 7mm Spacer to go between Stock Yaris caliper bracket and caliper extension bracket that comes with the brake kit

2. Longer Bolts I used 12mmx1.25mmx50mm bolts instead of the stock caliper bracket bolts

3. Nothing else

http://i369.photobucket.com/albums/oo133/111HP/IMG_0587-1.jpg

http://i369.photobucket.com/albums/oo133/111HP/IMG_0589.jpg

[wildmongoose26]

What all is included in said kit? The bracket for the caliper and the rotor and thats it?

Brent

[seth_man]

yeah, rotor, bracket, a few bolts

[Flipper_1938]

So, how much better is the braking with a bigger rotor and stock caliper?

[cali yaris]

^ good question. You have the same caliper/pad operating on a rotor that is now spinning faster. Braking might be worse, not better. It will definitely be hotter.

Overall though, very neat idea.

[yaris2010RS]

very nice...... this seems like a less expensive way to get a bigger brake look on aftermarket rims....


if only have a rear disk kit with less work....

[krusty]

^ good question. You have the same caliper/pad operating on a rotor that is now spinning faster. Braking might be worse, not better. It will definitely be hotter.

Overall though, very neat idea.

How would the rotor be turning faster with a bigger diameter rotor?

[cali yaris]

If you think about it, at the perimeter, a larger diameter "circle" has to travel faster to achieve one revolution as a smaller circle. The outside of a larger rotor is where the pad contacts it. I'm armchair discussing here, but I do know the friction would be greater to slow the velocity, causing more heat.

And all of that might not make a huge difference. Let's hear the OP's review!

[Spahrticus]

I just see stock pads being chewed up...

[seth_man]

^ good question. You have the same caliper/pad operating on a rotor that is now spinning faster. Braking might be worse, not better. It will definitely be hotter.

Overall though, very neat idea.


well first track day will be next sunday so i will find out. feels pretty good driving around town though.

I just see stock pads being chewed up...

some hawk pads are on the way

[eTiMaGo]

If you think about it, at the perimeter, a larger diameter "circle" has to travel faster to achieve one revolution as a smaller circle. The outside of a larger rotor is where the pad contacts it. I'm armchair discussing here, but I do know the friction would be greater to slow the velocity, causing more heat.

And all of that might not make a huge difference. Let's hear the OP's review!

That's true, but it's my understanding that the main advantage of larger rotors is to have more mass and surface area to dissipate heat from braking, so the temperature increase you mentioned may be canceled out.... food for thought! (and google searches :laugh:)

[Lil Abner]

You will still have the same angular velocity (rpms), but the tangential velocity at the outer diameter IS bigger (faster). However, you need to look at the main benefit of this system. The larger diameter of the rotor, and the pad being further away from the center INCREASES the torque the brakes can apply. Torque equals F X D (force times distance). So you should notice an improvement. As far as heat, I don't see that as a problem. Sure, aftermarket pads will help, but the stocks should work for now (unless you track the car).

[Kongo-Otto]

Centering the disc should be done by the hub not by bolts. And of course i would never modifiy a brake caliper this way.

Atleast in Europe that kind of engineering is strictly forbidden. :biggrin:

[Lil Abner]

Centering the disc should be done by the hub not by bolts.

That's a good point. I didn't see that when I first looked. Some rings to center the rotor might be a smart thing to do.

[cfeng]

If you think about it, at the perimeter, a larger diameter "circle" has to travel faster to achieve one revolution as a smaller circle. The outside of a larger rotor is where the pad contacts it. I'm armchair discussing here, but I do know the friction would be greater to slow the velocity, causing more heat.

And all of that might not make a huge difference. Let's hear the OP's review!

There are considerations necessary for matching a brake pad to a rotor. Usually, the inner diameter of the surface that the pad touches is 58% of the outer diameter, in order to achieve greatest braking torque.

[RedRide]

Consided a caliper brake on a bicycle.
You need relatively little caliper pressure on the rim as compared to the pressure you would need if it was close to the hub.
It's just basic physics.

[cdydjded]

^ good question. You have the same caliper/pad operating on a rotor that is now spinning faster. Braking might be worse, not better. It will definitely be hotter.

Overall though, very neat idea.

I think you might be confused on this one. The larger the rotor the less it rotates per mile, the smaller the more it rotates per mile. Think of tire sizes. A 205/40/17 has a diameter of 23.46" & rotates 859.80 per mile. A 205/50/17 has a diameter 25.07" & rotates 804.44 per mile. as you can see the taller tire has less revolutions. Here is a link: http://www.gtsparkplugs.com/TireCalculator.html

[Lil Abner]

I think you might be confused on this one. The larger the rotor the less it rotates per mile, the smaller the more it rotates per mile. Think of tire sizes. A 205/40/17 has a diameter of 23.46" & rotates 859.80 per mile. A 205/50/17 has a diameter 25.07" & rotates 804.44 per mile. as you can see the taller tire has less revolutions. Here is a link: http://www.gtsparkplugs.com/TireCalculator.html

Actually, no. You are correct about the tires rotating different per mile depending on the diameter. But that doesn't apply to the rotors. The rotors will ALWAYS rotate at the same revolutions per mile as the tires!!! This is because the rotors are attached to the wheels. The wheels to the ground.

[wildcard]

This thread haz revolutions...

http://userserve-ak.last.fm/serve/_/47170109/Prince++The+Revolution+therevolution1999.jpg

[yaris2010RS]

Actually, no. You are correct about the tires rotating different per mile depending on the diameter. But that doesn't apply to the rotors. The rotors will ALWAYS rotate at the same revolutions per mile as the tires!!! This is because the rotors are attached to the wheels. The wheels to the ground.

kinda true. the rotor center will spin at the same revolutions per mile as the tire but the speed of the rotor outer edge (the part that the pad hits) in relation to the pads themselves would be spining at a different speed then stock.

objects on the same shaft will have the same angular velocity but if they are different size they will have different linear velocity.

this is a tough subject seeing as the speed of the wheel is controlled by the shaft and the wheel on the road controls the speed (miles) at which the car is travelling.

you cannot use revolutions per mile to compare, my school website is down so i cant get to my notes or i would be able to tell you exactly what the linear velocity in relation to the brake pads would be.

[Lil Abner]

Yeah, that's what I posted earlier about the angular velocity compared to the linear at the rotor edge.

I'm sure the OP is wondering what happened to his thread. :-)

[yaris2010RS]

Yeah, that's what I posted earlier about the angular velocity compared to the linear at the rotor edge.

I'm sure the OP is wondering what happened to his thread. :-)

lol, atleast it didnt turn into an oil thread.... lol. everyone on YW kept themselves in check.

im excited to see how the new disks work out. maybe even some pics of them mounted. i would be very interested in a set as my rims look naked inside.

[Henry G.]

Seems like 10" discs brakes front AND back would fix the 2200 lb Yaris nicely...and kit for that?

[cdydjded]

Actually, no. You are correct about the tires rotating different per mile depending on the diameter. But that doesn't apply to the rotors. The rotors will ALWAYS rotate at the same revolutions per mile as the tires!!! This is because the rotors are attached to the wheels. The wheels to the ground.

You did not understand what I put. Obviously the tire & the rotor rotate the same revolutions. My point in using the tire calculator is cause you can use a taller tire or shorter tire which would apply to a rotor with a 12" diameter (taller) or 10" diameter (shorter). My point is no mater what it is a tire, a rotor anything with a circumference, the bigger it is the slower it rotates, the smaller it is the faster it rotates.

[Lil Abner]

You did not understand what I put. Obviously the tire & the rotor rotate the same revolutions. My point in using the tire calculator is cause you can use a taller tire or shorter tire which would apply to a rotor with a 12" diameter (taller) or 10" diameter (shorter). My point is no mater what it is a tire, a rotor anything with a circumference, the bigger it is the slower it rotates, the smaller it is the faster it rotates.

I get what you're saying, I just think you're using the wrong terminology. No offense, so don't take this as me being a d**k. When you say "rotates faster" or "rotates slower" you're referring to angular velocity, or the RPM's.

Look at it like what a previous poster said. If something has a set angular velocity (let's say 2,000 rpm), then you can determine the linear velocity at different points away from the center. The linear velocity at a point away from the center is (omega) * (r). (Omega) is the angular velocity, (r) is the radius. Looking at that basic equation, the larger diameter has a larger linear velocity than the smaller diameter since (omega) remains constant.

Tires and the rolling diameter is a different can of peanuts because they are driven from the center and the outer diameter.

Again, I'm just trying to help confusion, and not be a blankity-blank.

[ilikerice]

after reading this post, i think i have just been mind raped...

[cdydjded]

I get what you're saying, I just think you're using the wrong terminology. No offense, so don't take this as me being a d**k. Again, I'm just trying to help confusion, and not be a blankity-blank.

I take no offence whats so ever with what you are saying. Im not like some people here that cant have civilize conversations without getting pissed. Its hard for me to explain what Im trying to say, and maybe Im am using the wrong teminology. My basic argument is that the larger the rotor the slower it spins. Think of this, on a supercharger, if you want more boost, you need to spin the S/C more & that is done with a smaller pulley. If you want less boost you run a larger pulley.

[Lil Abner]

I take no offence whats so ever with what you are saying. Im not like some people here that cant have civilize conversations without getting pissed. Its hard for me to explain what Im trying to say, and maybe Im am using the wrong teminology. My basic argument is that the larger the rotor the slower it spins. Think of this, on a supercharger, if you want more boost, you need to spin the S/C more & that is done with a smaller pulley. If you want less boost you run a larger pulley.

:smile: I get what you are saying and thinking about. But you're thinking it the wrong way still. See, tires and pulleys have a relationship between the outer diameter and the inner shaft. A large tire/pulley having a linear speed of 15 feet/sec will have a slow angular velocity (revolutions per minute). A small tire/pulley with the same 15 feet/sec will have a LARGER angular velocity. So yes, you are 100% correct with all of that.

However, a rotor is totally different. It's not driven by the outer diameter, and the outer diameter doesn't DO anything to the system like a pulley (belt driven) or tire (road driven).

Umm, do you have a ceiling fan at home? If so, try this. Turn the fan on low so you can see the blades spinning. Lay on your back, and look up. Point your finger at the inner tip of the blades. Move your finger to follow the blades as you watch it with your eye (sorry, close one eye). Notice how your finger/hand is moving slowly to keep up. Now follow a point on the outer tip of the blade. If you're doing it right, your hand should be moving a lot faster to keep your finger on that point.

Another way to try it is a merry-go-round. Standing close to the center, you can notice you don't feel like you're spinning very fast. But when you go to the outer edge, you can tell you are spinning a lot faster.

I can understand the confusion, I honestly can. When I took classes on this stuff, I could see people getting confused until they ran some numbers or played with toys or something. I'm an engineer with over 3 years experience designing transmissions. Hopefully I've helped some. I agree, I hate people on forums who get pissed and yell. So I appreciate you not yelling at me. :biggrin:

[seth_man]

Yeah, that's what I posted earlier about the angular velocity compared to the linear at the rotor edge.

I'm sure the OP is wondering what happened to his thread. :-)


lol, no not really, its good conversation and some valid points. i know not everyone understands the math behind angular and linear velocity so carry on.

yes i am also glad it hasnt turned into an oil thread yet

i know the hub bores are not the same size and i measured the play in the stud holes and the rotor can only move .003 in any direction and .oo3 off center doesnt bother me.

its been raining here for a few days but ill try to get some more pics tomorrow, they do fill the wheel up nicely. :thumbup:


as for brake function at slower speeds just cruising around town they feel stock, but at higher speeds and pedal effort it stops, it stops very well. i cannot really quantify it or anything but i can say it stops alot faster when you need to, i will still have to see how the next track day goes but as of right now i have to say best upgrade thus far

[yaris2010RS]

how much was the kit? and i am more worried about the wheel feeling off balance because of the .003 (inch) give of play

[mazilla]

TAG

[seth_man]

how much was the kit? and i am more worried about the wheel feeling off balance because of the .003 (inch) give of play

ive had it sitting around, took it off a ctr that we put stock brakes back onto to run smaller wheels, owner didnt want them back.

i was looking around and ive seen used kits for sale on honda forums for $100-$200.

ive already had it on the highway and various speeds up to 90 and no vibrations. so balance doesnt seem to be an issue

[bobolinko]

If the Calipers mount at the same points or at the same distance from the Axle Center, there is no difference in the braking at all, so nothing changes except the size of the rotors.... That'd be absolutely pointless... Hope the Caliper mounts are away from stock, and SECURE. Just my 2cents...

[PHXDEMON]

So what gen civic was the BBK off of?

[Viperoni]

The extra rotor diameter will at least give you more mass to absorb heat and more surface area to sink it away. Useful in racing.

[mazilla]

Where's the OP with a final review, how are things holding up so far?

[seth_man]

Sorry for the delay everyone, ive been very busy with work, wedding plans n such.

so ive been to 2 track days since the rotor upgrade and about 2k miles street driving and everything is holding up great, no issues at all, i dont know if you can consider it an issue or not but finding 12.9 hardware to put in place of the stock caliper bracket bolts was not easy. M10x1.25x45 flanged bolts are not easy to find.

The first track day was done on stock pads and i was pretty impressed. there is a very noticeable in stoping power and much less pedal effort to get the desired braking. after the frist track day my new pads finally arrived. stock replaced with hawk pads. second track day was even better with the new pads. it took a little getting used to braking so late for corners i found myself nearly stopping before i got to a corner off a high speed section. it now seems that i can hold off breaking 40ft or so closer to a corner than with the stock pads and rotors. overall this car just became alot more fun.

[Lil Abner]

Sweet!!

[RXvedub]

I read threw a few of the posts that are not Seth's and didnt see this mentioned. This would mean you can use a brake kit made for a honda as a full BBK... right?

Anyone know if yaris and Echo brakes are the same?

[ASG14]

OMG, I think I just had a minddumb after reading most of this stuff. :eek:

I;m looking for a BBK for my Corolla, as well as my friend is for his Yaris, who sent me this thread. I HAVE to chime into this.

I have nearly an IDENTICLE setup to this on my Camry. I've installed it on several other cars. Stock caliper, relocation bracket, Supra TT rotor.

It;s track tested. And by track tested, my friend has done road racing on his local track with it. 300whp Camry. Not one issue. Couple others in Cali, same thing. My car can outbrake many sports cars.

Not goign into the physics with it, as I see another member here did an amazing job at that already. :)

http://i11.photobucket.com/albums/a193/14ASG/DSC_0277.jpg

http://i11.photobucket.com/albums/a193/14ASG/DSC_1727.jpg

[racerb]

Here is a short video on performance rotors from Stop Tech and Power Slot rotors, who also have BBKs for most cars. I'm going to use their rotors on my '87 Celica GTS racecar, with slotted rotors up front and drilled at the rear. Because I'm going to be using calipers and rotors from a '95 Celica at the front, I'll already have a thicker and beefier rotor, so slotted will work just fine. The rear is a solid disk, so drilled will disapate heat and moisture much better!

http://www.youtube.com/centricparts#p/a/u/2/_L_ev1iuGzg

racerb :w00t:

[RXvedub]

I have nearly an IDENTICLE setup to this on my Camry. I've installed it on several other cars. Stock caliper, relocation bracket, Supra TT rotor.


Hate to revive but what relocation brackets do you use?