The 2002 Mopar Performance catalog says the service part number valve spring for both the 300hp and 380hp crate engines was part number P5249464, so it should work perfectly for a stock Durango camshaft.
The problem is the retainers. The crate motors and service heads all used different retainers than factory Magnum beehive setup. Just have jdsduster check the springs he offered are straight, not beehives, and that will verify it.
