#60 over 4BT Conical Springs, Billet Retainers & Lock Kit
For the 8 valve 3.9L engines.
148lb seat pressure at 1.940 installed height / 245lbs. at 1.40 nose pressure on stock cam
Coil binds 1.3
Designed for up-to 3,700rpm max
safe for daily driving#60lb over stock valve springs are really only good for up to 40psi boost & approx 50psi drive pressure
If you are running higher boost then 40psi or over 3700rpm, you should consider a stronger valve spring set-up than this.
Lightweight 10 deg chromoly steel retainers that have been designed to mate perfectly with the conical spring shape. This retainer is much lighter in weight and stronger than OEM and other aftermarket retainers because of its reduction in size.
Also included are 10 deg steel valve locks to pair with these new retainers.
Don’t be fooled by people selling cheap springs out there. A broken spring can take out an engine.