Z95m6

I'm just wondering how the C5 setup is any better than the LS1 setup. I know the C5's have 13in rotors vs the LS1's 12in but other than that its the only diff. i really see. I've heard the Corvette caliper = LS1 caliper. So if the only thing diff is the rotor size how can that help in braking. The LS1 caliper isn't oversized for the rotor as far as i see. By that i mean the whole caliper makes contact with the rotor. So increasing the size of the rotor won't give you anymore contact surface. The only thing i could see is maybe an increase in leverage. You can turn a big wheel easier than you can a small wheel so maybe it works in reverse for braking. Any thoughts. I'm thinking about getting the caliper brackets for the C5's so that way i can have the 13in rotors mainly to fill up my 18in wheels, but is there any performance advantage?

Todd80Z28

That's exactly it, and it makes a big difference in braking performance. In fact, it's the key determinant.

eagleknight97

Not really. Leverage doesnt have that much to do with it. The big advantage to the bigger rotor is the more surface area for the heat that is generated while braking to be dissipated on. The more material, the quicker heat is dissipated and the more resistant to fade the brakes are. The C5 calipers are also slightly different. They have cooling fins running the whole distance across the top, while the LS1 calipers only have them running about half way. The pistons are also longer due to the C5 rotor in addition to being bigger in diameter, is also slightly thicker. So yeah, the C5's are definetely better. Especially in filling in the void when you add bigger wheels.

Highlander

IIRC both rotors use the same pads.. so they both have the same area of 72mm^2.

So its the leverage.. and total mass for absorbing heat that makes them better.

LT4Firehawk

No, they do not use the same pad. The C5 pads are actually different from the LS1 pad, although the caliper design is the same (they have different pad/caliper brackets). I believe that the C5 pads are actually larger, but I don't remember the actual size difference.

The main benefits of the C5 setup over the LS1 are:
more rotor mass, which gives more resistance to fade
larger rotor surface area, which helps cool them down quicker
stiffer calipers, pressure cast instead of gravity cast and extra/longer ribs
better leverage from the caliper being further outboard

Valkyn71

Brake upgrade newbie here.

Does the LS1/C5 brake upgrade just involve the front brakes? and the rear are the same on everything?

Also, what does it cost to upgrade to the LS1 and C5 setups?

And what kind of improvements will you see?

Highlander

Do a search...

The upgrade just involve the front brakes.. no need to do the rear.

Cost of the c5 is around $900 for new parts the ls1 would be aorund $300 for used parts

Huge improvements... HUGE!!! those are the brakes (c5) the fbody should have brought standard.

Red96Lt1

POINT 1
You apparently aren't an engineering major. "leverage" as you can call it, is the biggest factor. You increase the moment=perpendicular force * lever arm. To put that in english, the force of the brake caliper is perpendicular to the distance to the center of the rotor. So if you increase the lever arm (ie size of rotor) you will increase your moment, therefore your braking force.

POINT 2
You said the more material, the quicker the heat dissipates. Wrong, by having more material, the thermal mass is increased. The main factor to cooling something is surface area, the medium to which heat is being convected, and wether something is being forced convected or not.

Thermal mass can hurt you, because once you get it heated up (say on a road corse) it will retain the heat better than something with a smaller mass.

The only thing I agree with that you said is the cooling fins. That is an example of forced convection. And I'm not sure about the different caliper designs, so you could be right there. My main point was the rotor.

eagleknight97

Ha, darn right im no engineering major, im not stupid. And I really shouldnt have said anything about the leverage, cuz I was unclear as to what was exactly meant by that.

Red96Lt1

It's all good, I was just happy that I could put my Dynamics and Heat Transfer classes to some use.

Eff

Ummm.... to the best of my knowledge I understand why a bigger caliper, and a bigger rotor brake faster. But it seems that if you only had a bigger rotor, with the same sized caliper, and the same piston force, it would actually brake slower due to that fact that you now have a larger rotating mass.....
But then again, I'm kinda dumb. can you explain point 1 to me again as if I was a 4 year old

Highlander

No, not necessarily... you have more mass to disipate heat... i hope bob bishop chimes in...

The reality is that when you have more leverage and more mass to transfer heat to you should always see an improvement in braking.

WOT

The advantage of leverage and in some situations the stiffer C5 caliper* outweigh the increased rotational inertia. Think of how you use engine work to turn a supercharger, but the increased power provided by the blower overcomes the extra work.

Another advantage that wasn't mentioned is the increased swept area offered by C5 rotors. This will result in much better cooling.

Unless you're running road courses C5 brakes are a waste. LS1 brakes are more than adequate for street, drag, and autocross use.

*C5 calipers are pressure cast and have full width stiffening ribs as opposed to a gravity cast LS1 caliper. C5 calipers are much more resistant to caliper spread, especially at higher temperatures.

Highlander

they were saying all being equal...

yes the pressure cast is a huge difference in stiffness and the additional fins provide more caliper cooling that retard the fluid boiling... Now i beg to disagree that the c5 are a waste.... as a matter of fact.. the c5 come short when running at higher speeds that you normally don't see on auto-x or on short tracks...

Anyways... i make them fade everytime i use them

BTW i also have a b4c 94.

Red96Lt1

No problem the equasion is

Moment = force * distance (perpenducular to force)

So as you can see, if you increase either the force (bigger caliper), or the distance (bigger rotor), you have a bigger moment. The units for a moment is ft lbs. That will probably help.