It appears I need new springs for my 86 Camino. The build sheet says they are NHP for the rear, and DXY for the fronts. Can someone tell me what that really means.

I have to keep about 120 PSI in the air shocks just to keep the rear end up. I just hate a sagging rear end :-D

The front end bottoms out on a dip in the road I have to drive over to and from work.

Should I go with stock replacements or get something a little stronger?

Those are called "Broadcast Codes". If someone has a GM parts catalog there may be a chart in there to x-ref to a part number. After market is likely going to get you generic springs which may or may not be what you want.

Check out this place, they are Ford and General Motors authorized producers of authentic replacement springs.

Eaton Springs (http://www.eatonsprings.com/)