'The 383' ~ Getting Those True Factory Horsepower Ratings

Hard to Imagine

That the 1968 383/335 HP {Road Runner / Super Bee} Engine put out only
{+10 HP} over the 1966 and 1967 383/325 HP.

That was pretty funny.

Better Cylinder Heads
Larger Exhaust Valves
Better Flowing Exhaust Manifolds
Larger Exhaust Manifold Header Outlet
More Aggressive Camshaft
Higher Load-Rate Valve Springs
Improved Flowing Intake Manifold
Carter AVS {630 CFM} vs. Carter AFB {566 CFM}
Windage Tray