Urge Design / Essex AP Racing Brake Review
 

Pictures and review here:
http://sectoronedesign.wordpress.com/

The time has come for brakes with higher thermal capacity and less caliper twist/deflection. After reviewing several options, I chose the AP Racing front brake kit from Urge Design / Essex Parts:

http://www.urgedesigns.com/brakes.html

This kit uses a very lightweight and stiff 4 piston aluminum caliper and 32 mm thick 60 vane floating rotors. Because the rotor diameter is 299 mm (same as stock), diametrical wheel clearance is good. The thick caliper combined with 20 mm thick pads do interfere with the spokes on my 17 X 9.0 ET45 Enkei RPF1′s. To accommodate the brakes, I purchased TSW Interlagos wheels in size 17 X 9.0 ET63 which clear with less than a 10 mm spacer but I’m running a 15 mm spacer to maximize front track width without additional fender modifications.
This kit was impressive right out of the box with high quality hardware and nicely machined and finished rotary mount adapter brackets. Everything bolted up perfectly with no alignment shims necessary.

https://www.s2ki.com/s2000/uploads/g...983_213066.jpg

I installed Hawk DTC-70 pads and bedded them in per Hawk recommendations. Pads are cheaper than stock pad shape and have way more friction material thickness. Then it was off to Pacific Raceways for a two day NASA Time Trial event. Brakes performed flawlessly. Bias was spot on and feel was great. No change to driving style or pedal position. They did allow me to brake a little later due to the power and consistency. With the stock calipers, the pads would develop a taper due to twist in the caliper (likely the guide pin interface for the floating caliper). With tapered pads, feel is compromised as the pads don’t fully contact until the caliper is loaded enough to flex. The Urge Design AP kit had the same consistent feel from the first stop to the last stop of the weekend after nine 20-minute sessions. I dropped my fastest laptime from 1:30.3 to a 1:28.1. Pad wear was surprisingly minimal. Previously, I’d use up new pads (Cobalt XR2′s) in about 12-14 20-minute sessions.
So far, the rotors are also holding up to severe track abuse. Pacific Raceways has several high speed sections followed by heavy braking zones including slowing from 147 mph to 70 mph for Turn 2 and slowing from 120 mph to 45 mph downhill for Turn 3. These were tested on my TT2 S2000 which has 369 whp, weighs 2760 lbs with driver, and runs on Hoosiers. Won TT2 on Saturday and Sunday.
Rotors hit temperatures between 1075-1326 F according to the indicator paint.

Calipers didn’t even register on the temperature indicators with temperature of range of 300F-500F.
https://www.s2ki.com/s2000/uploads/g...983_514029.jpg

[media]http://youtu.be/-l4nFRY-I5w[/media]

A few additional notes.
These brakes kick butt. I was running RPF1's 17 x 9 ET45 which requires a 25 mm spacer to clear which would then require wide fenders. With the wheels I had kicking around, I did some test fitting and thought the results may be helpful to someone else. Note I only used 5mm increment spacers so some of the numbers below may be larger than needed. For example, the Interlagos would probably clear with an 8 mm spacer but 5 mm is not enough so I listed 10 mm.

AP1 Front Wheels requires a 20 mm spacer
AP1 Rear requires a 20 mm spacer
TSW Interlagos 17 X 9 ET63 requires 10 mm spacer
Enkei RPF1 17 X 7.5 ET48 requires 15 mm spacer
Enkei RPF1 17 X 9.0 ET45 requires 25 mm spacer
Volk CE28N 17 X 9.0 ET63 requires 10 mm spacer

I picked up some TSW Interlagos wheels for the fronts and am using a 15 mm spacer to maintain the track width compared to my previous RPF1's. The 17 X 9 ET63 Interlagos measured 18.4 lbs on my scale. RPF1's measured 15.6 lbs on my scale.

AP1 Front with 20 mm spacer
https://www.s2ki.com/s2000/uploads/g...983_597064.jpg
https://www.s2ki.com/s2000/uploads/g...983_597078.jpg

TSW Interlagos with 15 mm spacer
https://www.s2ki.com/s2000/uploads/g...983_146439.jpg
https://www.s2ki.com/s2000/uploads/g...983_114514.jpg

Volk CE28N with 10 mm spacer
https://www.s2ki.com/s2000/uploads/g...983_199261.jpg

And now I need to purge some extra RPF1's and unused front rotors/pads
https://www.s2ki.com/s2000/uploads/g...983_492836.jpg

Very Cool. Thanks for sharing the info on the spacer size needed to clear this kit! I've been wanting to run stock wheels for street use but havnt looked into what size I would need to clear.

Great information. I was looking at this kit and these wheels last week, lol.

Also what spacers are you running?

:thumbup: Great info. I didn't expect those Volks to clear with only a 10mm spacer.

Is it safe to drive on track with 20mm spacer? I may get the kit before new wheels/tires on ap1 if it is safe.

I use H&R TRAK+ spacers (DR Series) and longer studs.

Truly impressive lap times at PR Jared! Thanks for the write-up and the videos. Care to post your brake cooling setup?

Sure if you get extended studs, which are a big PITA to install. You usually need a new wheel bearing etc.

Pretty sweet man. Those brakes are badass!

Thanks! Brake cooling setup consists of custom air deflectors mounted to the lower a-arms and pointing at the center of the rotor. The dust shields are still in place but all material has been removed except at the boots/joints.