Re: GMC Savana coil springs
Get a MOOG Catalog and look up the stock replacement coils for your vehicle - you can get all the specs on that spring from the catalog and then look for springs with the differences you are looking for. You say you want "stiffer" but what does that really mean to you? Are you looking for more load capacity ("stiffer") or more ride height, or combination of both? Proper spring selection, while simple, is very misunderstood.
Four time Baja 1000 winner, four time Baja 500 winner. Solo'ed the Baja 1000 to LaPaz/Cabo twice.
4-Wheeling since 1972, Desert Racing since 1989.