Ceramic or Metallic Pads?

[Michael A.]

I'm looking for suggestions on brake pads to use on my 66 Roadster. The fronts are due for replacement.

I understand the ceramic and metallic pads provide better stopping performance than the standard "organic" pads. The ceramic supposedly stop the best and have the least amount of dust but apparently tend to squeak more. The metallic supposedly create more dust but are supposed to be quieter.

Any suggestions out there as to which I should install? If I go with ceramic or metallic, should I replace the rear pads at the same time?

Thanks,

[Joe L.]

Re: Ceramic or Metallic Pads?

I'm looking for suggestions on brake pads to use on my 66 Roadster. The fronts are due for replacement.

I understand the ceramic and metallic pads provide better stopping performance than the standard "organic" pads. The ceramic supposedly stop the best and have the least amount of dust but apparently tend to squeak more. The metallic supposedly create more dust but are supposed to be quieter.

Any suggestions out there as to which I should install? If I go with ceramic or metallic, should I replace the rear pads at the same time?

Thanks,

Michael-----


I would remain with the organic pads. I may change my opinion about this someday, but not yet.

Semi-metallic pads will be much harder on the rotors. I'm not sure, yet, what the effect on the rotors will be with the use of ceramic pads.

[Duke W.]

Re: Ceramic or Metallic Pads?

Even by today's standards the C2 brake system has very high capacity as measured by rotor mass and pad area for a car in its weight class. Also, the fixed caliper/multipiston per side design is superior for a maximum performance brake systems, but most modern cars have floaing calipers because they are cheaper and the systems will generate more brake torque than tire friction will support at which point the ABS intervenes.

If the system has a fault, it's that the rear uses the same rotor/caliper as the front, which was done as a cost reduction concession. The bias is 65/35 so the rear brakes only need about half the thermal capacity of the fronts, and a lighter rear rotors and single piston per side calipers would have worked just as well and saved some unsprung mass.

Probably the best general purpose brake pads ever available were the OE asbestos-based Delco pads for both road use and light racing.

The J-56 option did include semi-metallic pads because that system was designed for serious racing, but the other differences were minor.

It took the industry a long time to come up with non-asbestos organic pads that performed as well as asbestos, but current non-asbestos organic compounds appear to be as good, so a standard OE name brand replacement pad should work about as well as original, and unless you are doing serious road racing, you don't need any more.

Semi metallic or full metallic pads can offer increased fade resistance, but they have their downside - like chewing up rotors and a Cf that varies considerably with pad temperature. They can be a "fix" for cars with insufficient brake capacity, but such is not the case with the C2 disk brake system.

My understanding is that typical "ceramic" pads are tough on rotors and have a relatively low Cf, so they will increase pedal effort, which would not be good on a C2 disk system without power assist. It requires 120 pounds of pedal effort to produce a 1g stop on a C2 disk system with the OE pads - assuming you have that much tire adhesion, which would take a fully warmed up DOT legal racing tire.

My understanding is that the primary benefit of "ceramic" pads is low dust and low noise, I believe they are also relatively long lived, and on modern cars - nearly all of which have vacuum power assist - an increase in pedal effort will not be too noticeable to most drivers.

Duke

[Michael A.]

Re: Ceramic or Metallic Pads?

Duke - decision made, organic it is. I don't have power brakes and definitely don't need more pedal effort. Thanks for the advice and the lesson. It makes perfect sense.

Cheers,

[Jerry G.]

Re: Ceramic or Metallic Pads?

On my 64 road race car we have all sorts of brake issues. For a race car, old corvettes are big and all that power gets them going pretty well. At Elkhart lake( Road America) speeds over 180 mph are achieved. The pads we use are custom made with custom inconel backing plates. The pistons are not positioned in the stock calipers quite right so we get lots of top to bottom taper issues and front to back taper. One weekend is all we get on the pads and they cost around $600 dollars. Pistons endup being made from billit aluminum and special ceramic insulators are needed. Old Corvette brakes are really pretty good but, it would be nice to have 6 pistons and another inch or two of rotor diameter. Too bad we have all those pesky vintage racing rules.

[Duke W.]

Re: Ceramic or Metallic Pads?

I believe modern OE replacement pads have some sort of symbol to indicate that they have the same Cf characteristics as OE, and there is also a code stamped on the pad material that indicates the Cf range.

It's been a while since I researched this, but the vendor Web sites (Raybestos, Wagoner, Bendix, EIS) should have the info.

I know Pep Boys carries Raybestos, and I would not hesistate to walk down to the one a quarter mile from my house and order a set of Raybestos pads for a C2 disk brake system.

Since manufacturers often offer several brake pad product lines, it's best to look up the numbers on their Web catalogs so you can just order the part number rather than being asked 20 questions by the kid behind the counter who is half the age of your Corvette.

Duke

[Michael A.]

Re: Ceramic or Metallic Pads?

I don't expect I'll be putting my 66 to quite the same test as you put your vintage racer so I'll probably not be finding the limits of early 60's disc brake design. From Duke's post it looks like the General put a little bit extra into the 4 piston calipers of the Corvette system as they were in the early stages with one of their earlier forays into disc brake design.

I sure am glad I don't have to replace $600 brake pads after a weekend's driving! But I also sure like to hear about those of you that do! Keep driving and keep waving.

Cheers,

[Joe L.]

Re: Ceramic or Metallic Pads?

I don't expect I'll be putting my 66 to quite the same test as you put your vintage racer so I'll probably not be finding the limits of early 60's disc brake design. From Duke's post it looks like the General put a little bit extra into the 4 piston calipers of the Corvette system as they were in the early stages with one of their earlier forays into disc brake design.

I sure am glad I don't have to replace $600 brake pads after a weekend's driving! But I also sure like to hear about those of you that do! Keep driving and keep waving.

Cheers,

Michael-----


I think that pads GM #18028641, aka Delco 17D8, will provide braking performance equal to that of the original GM pads. These pads are the "direct descendant" of the ones originally installed on your car.

[Rick S.]

Re: Ceramic or Metallic Pads?

Michael,
I put semi-metallic pads on my non-power brake 67 and always had the feeling by sound and feel that there was grinding taking place. Changed over to organic and couldn't be happier, no grinding noise.