Spring rates

higher the number the stiffer the spring

Stiffer = better handling to a point

Note: Stock Mustangs have a spring rate of approximately 420 lb/in front and 200 lb/in rear

http://www.maximummotorsports.com/HRsprings.asp

I run the H&R SS springs on my vert, ride is WAY better then stock and handles like on rails.
Progressive is the only way to go on a street car, softer for the first 1" or so the gets stiffer for there......
 
softer ones give you better ride quality and better weight transfer for launching. you will spin less off the line generally.
you basically have to chose between really good handling and really good launching. either drag or twisties basically. progressive springs have variable spring rate, the more you compress, it changes, giving a better ride.
non progressive springs are the same the whole way.
 
RedBullitt said:
softer ones give you better ride quality and better weight transfer for launching. you will spin less off the line generally.
you basically have to chose between really good handling and really good launching. either drag or twisties basically. progressive springs have variable spring rate, the more you compress, it changes, giving a better ride.
non progressive springs are the same the whole way.

:stupid: I've got H&R sports and I have no complaints about them.