Having replaced the Eibach coils on my Cortex JRi setup three times now I can confirm some things.
1. Front needs 8" long springs with a helper (tender spring) setup. I have the 10" long springs on now and no matter what you cannot dial enough length out of them. range from 500 - 375 lbs / in. so far.
2. Rear can easily get away with 10" long springs but they also must have the tender spring setup or they will rattle at rebound events and over moderate bumps. 8" also work in the rear even with softer rates - I have not tried less than 225 lbs /in rear rate yet.
So no real need to go to 10" long springs in the rear, but since they fit why not. Front needs 8" long don't get the 10" they look right but turn out not to fit if you want to lower your car to a reasonable height.
1. Front needs 8" long springs with a helper (tender spring) setup. I have the 10" long springs on now and no matter what you cannot dial enough length out of them. range from 500 - 375 lbs / in. so far.
2. Rear can easily get away with 10" long springs but they also must have the tender spring setup or they will rattle at rebound events and over moderate bumps. 8" also work in the rear even with softer rates - I have not tried less than 225 lbs /in rear rate yet.
So no real need to go to 10" long springs in the rear, but since they fit why not. Front needs 8" long don't get the 10" they look right but turn out not to fit if you want to lower your car to a reasonable height.