Ford Capri front coil spring rated at 145lb/inch with open length 9.5"( 242mm).
Note that OEM springs ranged from 85lb/in on basic 1.6 models to 120lb/in on the 2.8i. So this 145lb is a very nice upgrade on road cars, introducing better control, but not so hard as to be uncomfortable.
Results:
Capri 1.6 and 2.0 will get approx -1" ride height.
Capri 2.8i will get approx -1" ride height.
Capri 3.0 will get approx -2" ride height.
Note that 2.8i was an inch lower than other models and this has been kept as an inch lower than other models in the final results. So, for example to get a 3.0 to sit at 2.8i ride you will need a spring that says -1" on the 3.0 results.
Results are based on MK2 and MK3 - note MK1 being lighter will probably sit half an inch or so higher.
Open spring lengths will be a lot shorter than original OEM springs, due to the higher ratings meaning that they simply won't compress as far under load. So, they have to start out much shorter, for example a -2" 190lb/in spring maybe 4 or 5 inches shorter than the original (not just 2") - this is normal and correct.
