Running full throttle at no load is a surefire way to do major damage to the rod bearings of any engine. If you're running a 216 with cast iron pistons, that's a very good way to hammer the Babbit bearings into nothing in a very short time. The engine will run pretty much forever at 3500 or a little more as long as it's done while pulling the vehicle. Revving it up in neutral is an exercise in stupidity.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!