Hood Springs

Best springs to use on a 69 Shelby Mustang?

The 69 Shelby uses a stock 69 Mustang hood spring.

Shelby owners are best to leave off the springs on the 1969 Shelby's to solve the hood bowing problem. 

The problem with bowing or warping hoods is due to the material of the hood - fiberglass instead of steel. The heat generated under the hood from big block engines plus accessories and even the heat generated from the fan drawing hot air across the hood, plus the hot sun on a dark colored car particularly is the culprit. The hood can be repaired by having a fiberglass expert split the hood sideways and take the bow out (the hoods are two pieces originally). No one seems to know what the original Ford specs were for spring tension on any of the Shelby's, nor is the original supplier(s) known, so that is a dead end street. The best suggestion is to carry the hood springs with you (me) to shows and put them on for the duration of the show, then take them off again. A spring of any less tension will probably not keep the hood up, so that is a trial and error thing and probably will not stop the warping.
In short, although the springs MAY contribute to the problem, they are a secondary cause of warping. The real culprit is the fiberglass/color of the car (darker colors retain heat)/heat generated in the engine compartment by the engine/accessories/fan blowing hot air across the underside of the hood (not necessarily in that order).
That information is straight from the horses mouth, so to speak, by a gentleman who has drag raced an original 1969 Shelby, who had removed the springs and still ended up with a warped hood. The car temperature never went above 1/2 way and he lifted the hood in the pits to help cool the beast. He has another 1969 convertible from new, always covered and garaged, with hood springs on, and because it has mostly been kept out of the sun, only a little warping on one side. Incidentally, both cars are the same color. Mystery solved? Maybe not completely, but the theory is sound. As to those of you with earlier Shelby's with springs that won't hold the hood up, sounds like a supplier problem. - Ronald Robertson