This is correct. So we have a short stroke engine that needs engine speed(piston speed) so Mopar puts a restrictive intake on it that checks out @ 5000-5500 rpm , along with a hydraulic cam that is designed to work from 1400-5000rpm, lets also put cast pistons that weigh a hundred pounds and leave them -.055-.075" in the hole for abysmal compression and non-existant quench, oh and then we can put restricitive exh manifolds on etc........ It's no mystery to me why they underperform in their OEM configuration. Take a look at Nicks video where he tests a 383/431--Look how much better that engine performs with the 3.75" crank. J.Rob