Joedust, I don't want to be offensive and you have a nice running combo but
Its a 340 he's asking about. You can't really compare a 340 to a 451. The 340 is much more sensitive to cam size. They make good horsepower but the torque has to come from gears and higher converter. A 340 with a 285 cam is gonna want to shift at 6800rpm as well.