The radicals were my favorite bbk to get but according to Z1 and conceptzperformance, the AP radicals I and II are not available/or discontinued which is littel odd

10/8 for now.

thats odd

anyone else heard this?

I was looking and heard the same thing, I saw Stillen even took them off the site. I did not try to contact AP.

Looks like it's across all platforms. Wonder what's up

This is one of the option I am looking in my brake upgrade, besides AP racing, I think oem sport rotors size is enough for our cars, so getting the caliper kit will be a very cost effective way to upgrade, also I think not all bigger brake kits will be compatible with 18 inch wheels, unless they come with same oem size rotors.


About 2-piece rotors, I have been using Z1 rotors, and they are working for me, I saw what happened to Austin in gridlife, I assume the time we get in track per session is short to put same type of stress on the rotors, but I drive it very hard when I hotlap my car. I used xp10/8 before, and changed to endless mx72 plus and I like mx72 better (even with used rotors). I was planning for XP12 all around but at the end went with endless.

Quick question - I run the same 2PC Z1 rotors on mine, the same Carbotech XP10/8 combo, and I also get significant pad judder. Could it be the pads? The judder developed after my first few days at Autoclub speedway on the Carbotechs. My car is a bit heavier on Hankook RS4, but also has stock power.

I'm not discounting the fact that it could be the rotors (it's so bad I've since switched back to the stock rotors), but just curious as the pads are an easier/cheaper fix.

I've read elsewhere that the Carbotechs seem to lend themselves to a lot of pad deposit, which may be the cause of the judder.

Bad rotors
Improper or insufficient bedding process
Bad hub?

I'm starting to wonder if the Z1 rotors and X10/8 pads don't like each other.

Instead further experimenting with different rotors/pads combos, I’ve decided to pull a trigger on stoptech trophy sport bbk with 380mm rotors option. Will do front upgrade only at this time and see how’s the balance. With right pad combo might get away with it. Haven’t decided on the pads yet though

Did the vibration go away after swapped to stock rotors?

I did a followup a month ago with Stillen on the state of the Radical kits for the 370Z.
They are the importer of the AP Racing Radical kits to the US, and stated they are discontinuing because AP racing was difficult to get parts in quickly.

I was pretty devastated because I've been eyeing the kit for about 2 years now and had just decided to spring for the Radical II kit.

I have 18 inch wheels so the stoptech 380mm trophy kit is too big, but the Radical II just fits.

My Z1 rotors are starting to show hairline cracks and my Akebono calipers are still leaking at the track, so I want a larger and thicker rotor to dissipate heat faster.

in that situation the Brembo kit seems to make sense

the only other big name alternative is fancy Endless/Project Mu stuff

I haven't been able to confirm as I've also switched back to stock pads for the street and haven't been to the track since.

How about their 355mm rotor option? That should fit 18inch wheels