318 simple bolt on setup for more horsepower

I call bullshit....
I believe him, I could get 20 mpg in that Dart with the 318 and 340 intake and TQ when it had 2.76 gears.
But I had to keep my foot out it, run the tires at 34 psi, AC off.
And that was with the 14" ralleye wheels and narrower tires than it has now.
Normal fun driving gave about 15.