Originally Posted by Sonic Mustang
Well, there goes logic.
A heavier car will require stiffer springs to obtain the same levels of performance as a lighter car. That's why convertibles have different spring rates. IT DOES MAKE A DIFFERENCE.
The OP should take a look at H&R springs. They are very high quality and available in different rates and ride heights. I'm running Super Sports on my Mach 1 which may be a little too low for a real daily driver, but H&R makes springs that leave the vehicle at original ride height and others that drop it about 3/4".
If you read the original post and my reply, the logic is there, you just failed to comprehend it.
IF Ford OEM offers different spring rates (stiffness(es) for Vert and Coupe...yet aftermarket doesn't differentiate...it is because the aftermarket rates are already stiffer than what the OEM offers for either version so they do not differentiate (or feel the need to differentiate). So to be more clear/concise, aftermarket doesn't necessarily feel it matters.
I never stated that the performance would be equal for the same rate on different models did I?