Engine runs perfect until you hit 4400 RPM and then it just stutters. It won't go beyond that. New plugs, wires, cap. rotor, crank sensor, TPS, air filter, oil filter, oil. 62,000 miles. 2001 ram 1500 truck. 318 engine. Stock program or superchips 87 octane program have same result.

 

Sounds like valve float, it might need a new set of valve springs.

 

I thought about that, but on an engine with this low of mileage?

 

I don’t see fuel filter or pump in your list of parts changed…

 

Rev limiter if it has one maybe gone bad?