Update.
Got pissed off because everything we tried didn't work, pulled out the new engine and dropped the old Adams "pooch" motor back in the car. Twisted 6200 rpm no problem, sent the concept back to the builder who put it on his dyno and says the motor is fine. Told Maria she burned the plug wires and that is why the car wasn't running right. Evidently he feels she is an idiot, she has been racing for many years already, her brothers race, her dad raced so she is no dummy when it comes to cars and engines. She then mentioned to him that the wires he said she burned were brand new race wires with protective boots and if they were burned it happened running one straightaway on a 1/4 mile track as she ended up in a wreck and went to the pits. He is claiming that those plug wires may work on her Adams motor but will not work on the concept motor. Really? Same distributor, same MSD box, same everything used on both motors but Adams runs and the new motor dies off at 4900?
If I was a betting man I would say there was a valve issue and rather than admitting he f-ed up he is figuring that being Maria is a girl he can blame it on plug wires and she will just buy it. Guess we will know when the motor comes back and we run it.
Thanks to all for their help, we tried everything you guys suggested and then some.