ive done the math, and tested it out to boot.not too sure about 115 on the speedo being 105 real mph, guess that depends on a traction,etc.i will say this,my buddy just bought a clutch kit from hartman,and i have tried the sled,its fast, 107 on the speedo in an 1/8 mile.mine only reads 105, that is what im geared for,and he has the same gearing.i beat him by 8 lengths in 1000 ft, and was 15 lengths in an 1/8 mile.so you tell me how i can be faster, or quicker.