[Mike C]

You can probably squeeze low 20's out of it. Slam it to the ground, air dam, 225 70 15 tires all the way around. Get the high pressure rated ones and run 44# air pressure. Keep open diff in the rear and get a 4.8 LS motor from a late model truck.

Weight is fairly low on these trucks, lower rolling resistance, keeping turbulent air off the bottom. Effiecient, smaller displacement engine. I'd just fine one that has the 6 speed auto trans behind it.