Hi Sean - good to see you back its a 362x32mm. Its designed for a short race so avoids the weight of a heavier duty 36mm BTCC stylee rotor, that said the package has done two endurance races totalling 36 hours one in Dubai with some challenging ambients and the other at Mugello. The bell design is worth as much as 140 degrees over an OEM rotor and a couple of teams are running them without any augmented cooling at all which I think is the designs biggest compliment...
Sooooo......Calipers
So generally for motorsport purposes stuff just needs to work, you won't find K-Sport, XYZ, Hi Spec or other anodised pacific rim items. Theres been a general attitude change about the VWR Cup recently, technically you could still turn up in a privateer Mk1 Rocco or a Mk3 Golf GTI and race but for the last three years or so maybe even longer its been generally moving along to a significantly better funded and more competitive race, theres some significant sums of money being spent which in some ways was inevitable but also a little sad. Theres a big shift this year to Sciroccos which represents a bundle of cash as a donor vehicle in its own right. The TV coverage is welcomed by many but brings its own pressure amongst the builders to succeed....
So we use the CP5060 Caliper, its a six potter with dimensions to take the 3894 pad which is very popular and is also the pad shape for BTCC this year, the pads are relatively affordable ranging from £100 plug and play 1 race specials to over £600 more on pads later...
Ok so the caliper gets no paint just an anodised finish, no dust seals, no anti rattle clips. Its very accurately machined and is designed to be very rigid even though its two piece, piston sizes are a very good match for a 23.8mm master cylinder but thats fairly incidental as all the guys are running pedal boxes from either Tilton or if they have too much money AP.
You can see from the pic that the small piston is indeed quite small - this is about pedal feel the small piston will deploy furthest for a given system pressure so will reward the driver with good bite and responsiveness, the power for the big stops is available from the 2 & 3 pistons even though as soon as the pedal is moved they're in the game too - the sizes arent just guessed at they are designed so that over the cause of the race you don't get pad tapering.
So the calipers are available in leading or trailing config - the smallest piston has to "see" the disc first on rotation, the calipers are also available with stainless pistons but not many guys spend the extra £100 with these being around £600 a corner anyway. They get checked over to make sure the caliper is in the right box and then the temperature strip is applied, the strips arent necessarily calibrated but they are accurately made in respect to each other....so its easy to check on either caliper to see if the marks are the same to see if you've got a hot side.
Its a Pro5000 caliper which means that its a fairly common stock item for AP which they manufacture in good numbers, unfortunately stock is always an issue with AP currently...its been a real challenge to make sure we have all the orders fulfilled but we got there in the end.
Pads and bracketry next when I get a min......
