First tech post for me. Be kind

2001 C5 Convertible Base. Ive had the car for a week. 82K miles with what appears to be stockish replacement rotors. Grey hats. No much wear on rotors as far as I can see without pulling rims.

Issue... the front rotors feel like they are warped. Low speed(under 15 mph) they have a tendency to do the "headbang" where the torso bobs back and forth. At any speed above that the front end shakes side to side. I have read quite a few threads from as far back as 2021and my eyes are crossed. LOL. I am looking for a quality replacement set up or kit that stays within a budget of about $300 or so. I just want to enjoy the car BUT i do plan on a few high speed blasts and maybe a bit of spirited chicanery.

Seems as if the consensus is NO holes due to cracks, Centric rotors but Im not seeing the 125 series for sale at the present and ceramic pads to keep the dust down.
I have read about stock rotors/pads as well. To be honest, the Raybestos wavy slots are priced right as well. I dont know, sometimes too much info just confuses me.


So, recommendations would be appreciated.

 

It is unlikely that the rotors are warped and much more likely that they have uneven pad deposits on them.

Stop Tech published a paper on this a long time ago. Looking for it, it looks like Stop Tech has been absorbed by Centric. Check technical bulletins:

"TECHNICAL WHITEPAPER: Removal of Uneven Pad Deposits with Aggressive Friction Uneven pad deposits can often be effectively removed from rotors by using a pad compound that is more abrasive at lower temperatures. StopTech has found the Hawk 9012 (Hawk Blue) compound to be particularly effective in removing uneven pad deposits from rotors. Other higher temperature performance pads may also effectively “scrub” off uneven pad deposits, however we have found the Hawk 9012 to be the best for this application. WARNING: Only keep abrasive pads in place long enough to remove the uneven deposits. Leaving pads that are abrasive at low temperatures in service on the street longer than necessary will dramatically wear the rotors. Before installing the replacement pads, characterize the vibration issues you are trying to cure. Drive the vehicle in a safe area at different speeds using different pedal efforts to get a good feel for where the vibration is most noticeable. Make notes if necessary to track progress of vibration abatement. After characterizing the vibration, replace the pads with the Hawk 9012 or a suitable alternate pad. The key to effectively using the pads in their abrasive mode is to brake aggressively enough to remove the uneven deposits, but not allow the brake system to get hot enough to have the Hawk 9012 pads start transferring material to the rotor. A series of 3 consecutive decelerations from 60 to 30 mph is a good guideline. The decelerations should be very aggressive (80-90% of the effort needed to engage ABS or lock the tires) with no cool down between the 3 decelerations. After 3 decelerations in a row, allow the system to cool by driving passively and avoiding hard use of the brakes for several minutes. Repeat approximately 10 cycles of 3 each decelerations."



I would first try a standard pad break in procedure with the pads you have- five stops from 30 to zero followed by two stops from 50 to zero all sequential without allowing the rotors to cool in between and see if it makes a difference.

If the pads are not worn past half thickness that may be all you need to do.

After 13 years and 26 days on road course race tracks I think plain solid rotors are fine street or track with the right pads.

 

I did as suggested. I also did a couple of 65-0 mph stops to get a feel. Braking has improved, not a violent shaking as before. Yet there is still some wiggle in the wheels as brakes are applied. I think some of the "headbanging" was the transmission downshifting, exacerbated by pad build up. I did notice some brake odor after the 65 mph stops but not unexpected.

When I get a chance, I will pull the rims and check run-out with a dial indicator. If rotors aren't too bad then a skim on the brake lathe and new pads should do the trick.

I'm thinking semi-metallic pads. I am not worried about dust or rotor wear as these are basically consumable items anyway.

Anyone want to suggest a set of pads for plain rotors?

 

I have used Hawk HP Plus Pads: December 2013- January 2019, 9 track days on plain rotors; January 2019- present on Stop Tech cryo treated slotted rotors, 10 track days so far.

For me the HP + pads provide very good bite street or track -- BUT they dust the wheels.

In my view there is no good reason not to use plain rotors street or track. Knowing what I know now I should have just replaced the plain rotors with plain rotors. In threshold braking, HOT brakes, the slotted rotors cause a distracting vibration that plain rotors do not.

My car is on its 5th set of pads since 2011. I have never turned the plain rotors or the slotted rotors.

If you track the car on a road course, do NOT let the pads wear more than 50% of new thickness or you will risk burning the rubber caliper piston dust covers to carbon tatters. Ask me how I know.

 

Just to wrap this up..

I bought a kit from Tire Rack that included Centric 120 rotors and Hawk HPS pads. I also procured a new set of shims and rubbers. Grand total was just under the $300 budget.

Im satisfied with results so far.