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While changing the brakes, the brake system was bled using Stoptech's high performance STR 600 brake fluid. Stoptech High Performance Brake Fluid is a DOT 4 brake fluid, engineered to optimize brake system performance, including ABS, at high operating temperatures. In addition to guarding against boiling and subsequent loss of efficiency at severe racing temperatures, StopTech brake fluid maintains its excellent viscosity, lubricity and non-compressibility. STR 600 has a dry boiling point of 594 degrees with a wet boiling point of 404 degrees with a minimum wet boiling point of 383 degrees. A resealabe metal container gives STR 600 a 25% longer shelf life over porous plastic containers. 
Our new brake system was subjected to ten 60-0 stops, ten 80-0 stops and six 100-0 stops performed in rapid succession. The brake upgrade was tested with just the Stoptech front kit and the front and rear kit together. The brake temps were measured with an infrared pyrometer and a contact probe. 
For just the front kit only, the brakes were 16% cooler in the 60-0 test with the rear brakes maintaining the same temp as stock. The stopping distance was 3% less than stock. At 80 mph the front brakes were 27% cooler than stock with the rear brakes 20% cooler than stock while the stopping distance was 3% less than stock. The improved function for the front brakes is also reducing the stock rear brakes' operating temperature. Stoptech tell us that this frequently is observed when just upgrading the front brakes. At 100 mph the front brakes were 21% cooler than stock with the rear brakes 14% cooler than stock with the stopping distance 2% less than stock. There was little brake fade and brake function was perfect.
Next the test was run with both the front and rear big brake kits installed. At 60 mph the front brakes were 34% cooler than stock with the rear brakes 70% cooler than stock.The stopping distance was 4% less than stock. At 80 mph the front brakes were 23% cooler than stock with the rear brakes 65% cooler than stock. The braking distance was 4% less than stock. At 100 mph the front brakes were 20% cooler than stock with the rear brakes 58% cooler than stock. The stopping distance was 4% less than stock. The overall brake balance and ABS function was perfect with either configuration. There was little fade and no smoke and fire antics as we'd experienced with the stock brakes. 
In the J-Turn test the car exhibited perfect stability and the front wheel radius measurement was acceptable. 
The J-Turn rear wheel radius measurement was within acceptable parameters as well. If you want to full understand Stoptech's brake validation methodology, please follow the link below and read the last article for all the details. By the time you read this the VA WRX kit will be available for sale. Like all Stoptech kits we have experienced with our various project cars, the kit is wonderful, with a nice hard pedal, good modulation and a throw out the anchors confidence that unflappable brakes gives you.
That we got pretty acceptable improvements, even on a car like the VA WRX that has pretty big brakes stock is testimony to how well this kit works. If you are a track day geek, this kit will not disappoint and heck it even looks real good. Our kit's performance validates our opinion that Stoptech is one of the best brake upgrades, especially when the car's stock electronics and hydraulics are going to be maintained.
Read about Stoptech's brake system validation process here!
Read more about Project VA WRX here!
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