can someone confirm horsepower?

i had a 1990 w150 4X4 club cab. I was very pleased with it. it was real tourquey, it could boil the tires at will. It only got 16MPG on the hiway empty. the thing that hold back any mods are the camshaft & TBI injection, although they came with the 308 heads on them. it would run with 350 chevs & run & hide from the 351W fords of the period.