power to wieght ratio

I am trying to find an equation that will give me power to wieght ratio of a couple of cars...anyone?

it's easy.
Power/weight = power to weight ratio.
usually measured in HP/Ton in the US.

i thought it was hp/lb

Take your car's weight and divide by the horsepower. That will give you the weight per 1 hp.

Anything over 25lb/hp i believe is considered underpowered.

by those standerds my aspire is powerfull enough