Imagine you're an engineer. Your boss asks you and another engineer to build a 5 liter engine. Yours has a flimsy valve-train and makes 370 horsepower. The other guys makes 435 with a stable valve-train. Which one is better engineered?
Of course its better designed, less cubes, similar power, lighter, what more do you need to understand.
The chassis are within about 4% of each other, so pretty close, and handle near the same. The displacement is 25% more, that is huge.
The engineering of the Ford is superior, hence allowing more HP/CI. The physics require more space to accomplish that feat. Its not a demerit. Its also amazing that its lighter with all that added technology vs the LT1.
The fair way to measure a class is lbs/ci. So power per specific volume is an entirely valid metric. That levels the playing field. No different than specifying if a class is NA or forced induction. And when you do this, the Ford kicks ass. Otherwise people would be stuffing 1300 ci V16 Allison...
NHRA prostock was the last good measure when it was a lb/ci class. All factory cast iron. And Glidden proved Ford was the king. So all you chevy (and dodge) lovers can go pound sand. If it were the same way today, as in factory block and heads, and lbs/ci, Ford would rule today too.
To be honest, I dont trust anything posted as "stock". There is a reason they re-flash the coyote stock class cars before every run, and those guys are watching each other. There is a shitload of things you can do to knock a few tenths off that are not visable. I think the rush to be on youtube...
Maybe in the warranty period, but as an example, it was hard to find an old style 5.0 that were left stock. When you look at the GT's many more than 5% will see mods by the time they are 4 years old, and any you encounter at the track I'd say 95% will be modded regardless of age. The size of the...
Plenty of room left in this V10 engine bay:
http://image.mustangandfords.com/f/9316049+w650+h650+cr1+st0/138_0402_z%2b1999_ford_mustang_boss_351%2bengine.jpg
A 4" bore Voodoo would be a 6.0 liter, and about 1.2 inches longer (moving the bore cntrs to compensate) Ford had a chance to do this with the Coyote but saved money by keeping modular tooling. I'd like to see them use the same philosophy and reuse the V-10 tooling with Voodoo heads architecture...