Sometimes its the simplest thing(s), cool stories!
Closest I have is from when I had my '77 Gran Fury cop car back in HS ('84).. While it had considerably more power than the tired '73 Satellite 318 I had before it, it never had the
power I was expecting. Cop car still had all the Lean Burn stuff on it. One night, unrelated to the 'Lean Burn', the dash wiring caught fire, so I yanked the drivetrain and junked the rest. Fast forward a few years, and I decide to put the cop car parts into a '76 Club Cab I had replacing its very tired 360. To replace the Lean Burn parts, I used an earlier TQ and electronic ignition and I used headers. Never cracked the engine open, just gave it the most basic of tunes to get it running..........
Compared to when it was in the car............
It was doggy around town due to the higher gears from the cop car, but DANG! Above 50 MPH, it pulled
HARD. I literally broke the needle off the truck's 100MPH speedometer one night.
Crazier still was that 440 gave me better MPG than the 360. Go figure.