Switching brake pads

[Bill Johnson 42]

What's the current thought on switching brands of brake pads, do I need new rotors to go along with them?

Have had my old rotors in my parts tumbler and they look close to new but not quite all the way there.

[DanW]

It depends on the compound you were using and the compound you want to change to. Some are no issue at all to transfer new material on break-in, others need the rotors resurfaced. Check with the pad supplier you are using.

[Raceworks]

What's the current thought on switching brands of brake pads, do I need new rotors to go along with them?

Have had my old rotors in my parts tumbler and they look close to new but not quite all the way there.

It depends. Generally I've seen zero issues going between compounds from the same manufacturer. Switching manufacturers may require more work depending on composition of both the pads and the rotors.

When I was still in Formula Mazda I bought out one of the other prep shops and part of what I got was a bin full of PFC, Hawk, and Cobalt pads. There were some Ferodos too but I sold them immediately. The rest I cycled through as a sort of experiment on the relative merits of the various pads. They all had their different strengths (the Cobalts had the best "cold" grab while the PFC's could take the most peak heat without fading) but overall the lap times didn't really change. I don't recall ever having to do anything major switching between the different brands: I'd just rough the surface of the rotors to break the "glaze" and bed in as normal.

[John LaRue]

Current generation pad material functions by establishing a transfer layer on the mating rotor. Depending upon the pad composition and existing transfer layer it may or may not be possible to establish a new transfer layer on the used rotor. If you are serious about your racing you will either utilize new rotors or you will take a light cut off of the surface of the rotor to expose fresh iron. John

[Bill Johnson 42]

Thanks John - Guess I'll get myself some new rotors for Christmas

[John Robinson II]

The other option is to bead blast the rotors. I have done this several times switching pad manufacturers.
I tape off the hats and thoroughly clean afterwards.

Jkhn

[R. Pare]

Thanks John - Guess I'll get myself some new rotors for Christmas

Bill, you only need new rotors if the current ones are badly worn - like with grooves - where the new pads will not fully contact the rotor surface. If they contact well, all you need to do with a non-metallic pad is to thoroughly clean the rotor surfaces of the old pad material. If a carbon-metallic, like the PFCs, you need to have them turned about .007-.010" per surface to remove the material that has impregnated down into the surface.