[jj_mdx]

just read a review article about the pilot at edmunds.com, found some interesting comments as listed below:

"For the adolescent in all of us, the Pilot comes juiced with a 3.5-liter V6. With only minor variations, it's the same mill found in the MDX and Odyssey. And as with virtually every other Honda and Acura vehicle, the engine features the VTEC variable-valve timing system to improve high-end power, low-end torque and fuel economy. The engine makes 240 horsepower at 5,400 rpm and 242 lb-ft of torque at 4,500 rpm. (The MDX makes slightly more torque at a lower rpm thanks to a more advanced intake manifold.)"

maybe that's the reason why mdx requires premium whereas pilot/oddysse only asks for regular gas...

 

[DaleB]

There's obviously a lot more to engine tuning as the article implies. Camshaft grind, the way the processor is programmed, etc.
Might be interesting to see the HP and torque curves of the two engines side by side.
Within the performance profile is the answer, not just in numeric values. It's how and when the power is delivered that makes the difference. Assuming both have the same gearing in terms of road performance.