MPH doesn't matter. I think i hit like 85 or so and i was around a 16.5. I had a buddy that changed his rear end from a 2.83 to a 3.83 and ran a 14.9. he used to be a at 15.1. He had a slower top end after he changed out the rear end compared to his 3.83. I wish i new the speeds, but i don't.
Before he changed his rear-end, i could hang with him from a stop and he'd gradually pull away on the high end. Now after he swapped them out, he pulls like a bat out of hell. but i would catch him after he hit 80mph.
Not too shabby though good job