They aren't stoptech rings on this kit. So buy whatever you want for the v8r hats. AP racing, wilwood, coleman. whatever.

When will these be on the website?

It's all about the gram.

This ^

Same 11.75" rotor ring flexibility as other 11.75" kits. So you can run <$40 wilwood rings, baller AP rings at $134, etc. Even on cars that usually run the good rotors, we really like having the flexibility to be able to swap in the cheap rings for testing new pad compounds.

^^^
speaking of good rotors...

can you tell a difference?

Yes, the wilwood blank econo rotors serve their purpose, but don't count on them for more than 14hrs of track life. That's less than my pads last

You can't tell a difference from the driver's seat in a single braking zone, but the differences are big and still very tangible.

For a while I ran IR sensors on the rotors. Initial temp rise in the first few opening laps is similar for budget rotors vs. good stuff, with differences showing up in the rate of cooling while the brakes aren't in use. After a couple laps the differences become more pronounced. A few laps in, the good rotor's temperature begins to slow their trend upwards and the budget stuff is still rising at a fast rate with each braking zone and not cooling as effectively during each gap between braking zones. After several laps the good rotors level off where the graph of each lap looks more or less like a repeat of the one before. The cheap rotors (hopefully) reach a similar leveling off point eventually but when they do it's at a higher average temperature.

Ultimately the good rotors are running significantly cooler over the course of many laps than the budget stuff - and that directly translates to much longer life, less warping, less heat in the rest of the system so less likely to boil fluid, overheat pads, etc. therefore more consistency, etc. etc.

This is exactly the kind of information I am/was after.

Thanks for not being a fucking dickhead like a lot of other people on this forum!

+cat

Makes use of every bit of swept height available:

https://photos.smugmug.com/20152017-...3ig1sma-XL.jpg

https://photos.smugmug.com/20152017-...kzzousf-XL.jpg

So much win in brakes and wheel stud fail. Any info on the upper ball joint?

Great to see more options out there to respond to the assortment of needs and preoccupations.

Having pad dimensions is really nice as I find most qualitative comparisons in pad size are done relative to a non-sport stock pad.

It would be really nice to also know the usable pad volume on each of these shapes to help everyone make the right trade-off for them.

As someone else asked, when will these StopTech kits, ST42 and STR42, be listed on websites for sale?

Not really. Those are good studs that came pre-installed in the fresh Centric hubs. I don't run spacers and thus have plenty of thread engagement with the 949Racing lugs. No need to change it. With as much as I've cut the car apart and rebuilt it, this may sound like a contradiction, but I am still a proponent of not f*cking with something if there isn't a good reason to.

The upper ball joint is V8R's rebuildable unit. Just installed so will be testing it soon.

That a nice swept height, thanks for the pictures. It might not hurt still to get a custom pad cut to get more pad material on the inner radius of the rotor. Wendy at Porterfield has been awesome to work with on projects like that, and not expensive either.

Interesting too how low the brake line connects, no issues with clearance I assume, but just something to note. The calipers are not universal left/right either it looks like.

Consider that the caliper uses abutment plates to locate the bottom corners of the pads, so you can't change the lower pad shape in the way you're envisioning.

The calipers are staggered piston sizes so definitely left/right specific.

Basic info and pricing uploaded.

Fair enough. I thought the consensus was to replace the studs for added insurance on track-driven cars. Looking forward to seeing results on the ball joints.

Details on IR sensors? Have been kind of looking into the best way to do this; it seems like most of the available IR sensors don't want to deal with brake rotor temperatures or maybe I've been looking in the wrong places.

It was a prototype kit put together by member Cyotani on these forums. Stand-alone data logging system that wrote to a SD card with four IR sensors in 3D printed cases. Mounted the sensors to the brake cooling ducts with a hole drilled in the duct for the sensor eye to point at the inner facing rotor surface. A little buggy since it was a proto but got some great data with it. There are production kits out there, they're just $$$

I am looking at kitbashing together something almost identical so was literally looking for what sensors were in the cases. ;) Is there a thread (nevermind think I found it, I'll just dig that up from the dead)

When I was in college, our FSAE team had a thermal imaging camera laying around that could log, so we taped it inside the nose of the car and did an autocross run. You don't end up with raw data as you would with a thermocouple, but it's another way to visualize it if the equipment is handy. If IB cooperates, you should see a couple autocross runs. This was done in 2009, so it looks like it was taken with the original TI calculator. Interesting bits start at 1:00.