Preheat oven to 400°F. Bake pie crusts, weighted with pie beans, for 10 minutes. Remove weights, prick crusts, and bake for another 10 minutes. Cool. Combine sugar, salt, spices, and pumpkin. In a separate bowl, beat together eggs, cream, and molasses. Combine two mixtures and beat. Divide filling between pie shells and bake for 10 minutes. Reduce heat to 350 degrees F and bake for 30 minutes, or until a knife comes out clean. Cool. Serve it with whipped cream, if desired.