The S10 EV was produced between '97-'98, GM built over 500 of these trucks, but only 60 or so were actually sold to the public.
used an electric motor...blah blah blah...anyways, to get on topic, the truck had some mods done to it to improve aero:
a unique lower bumper valance, a closed grille and a front air skirt, belly pans beneath the front suspension, a seal between the cab and the pickup bed, and a half-length tonneau cover over the rear of the pickup bed. One other odd thing about the truck is that is it FWD.
GM raced one at Pikes Peak in '97:
While the aero improvements would be nice to implement to our gas thirsty trucks, cooling is def an issue.
anyways, to add to the topic, I found a guy on mpg sites that put a rather ugly but effective front spoiler on his 4x4 s10:
he used Extra deep garden edging 6" deep x 20 foot long coil purchased at ACE Hardware for approx. $12.00.
he claims his hwy mpg went from 18.5 to 20 mpg using this. He later added an extension that looks horrible but he says added another .6 mpg to 20.6mpg.
of course we can't use such a large valence, but they do offer smaller edging pieces if you wanna go that route. Personally I'd like to find a chin spoiler off of something (like the zq8 'rado's) and try it.
