i think your fucked but the easiest way is to just put it on the dyno and see how far off the speedo is.

hell stock they are off atleast 5-10, throw in a gear, I'll guess i down 2 up which should put you almost 30mph faster than your really going.

45+15 =60 + that 30 your speedo is reading high.. so you were doing about 90 when clocked?


anyways, random guess, cause i'm bored today.