Bought my '94 GMC k1500 (3.73 gears, tow package) in '16, spent 3 years trying to tow with it, making improvements constantly, 2- 4" direct air intakes, MSD adjustable timeing control, dual exhaust (no cats), Fastchip. Nothing worked too good, kept cracking exhaust manifolds because I liked blasting up mountain passes in 2nd up to 4,000 rpm. So, replaced it last October with a 383 stroker. Now that is an engine for towing. Can tow a 5,000 lb travel trailer in 4th, has oodles of torque. Right now Old EFi is tweaking a chip for me using TunerPro RT. Got the remanufactured engine from S&J engines in Spokane for $2300 with roller cam, can't beat that. Now I can go as fast as I want when I want, but always keep it around 65 mph for the sake of the trailer tires and safety.