My 57 10500 Fire Truck with the original 322 Buick will run all day long at about 62 mph. It has a 2-speed rear (6.14/8.36:1).
My Tow Truck has a 350 small block that replaced the original 265 and it will run in the mid 70's with the 2-speed rear.
The chances of there sitll being a compressor in the truck are slim, they were bolted to the top of the motor...no motor/no compressor!
My 56 LCF (future restoration) is an Air Over Hydraulic Brake truck with the Allison 6-speed automatic and power steering...very rare!
Tell us more about your truck after you have a chance to look it all over!!
Mike B.
