3 things that the Z/28 has going for it vs other factory production LS7s.
1. the cold air intake.
Even though the accordian tube is still going to be restrictive, it has an open element air filter with a heat shield.
Electric power steering has shown some impressive gains over '12 SS LS3 cars.
My '13 LS3 car baselined 19 RWHP and 22RWTQ over my '12 SS. Same dyno except the '13 got dynoed on an even warmer day!
That View of the LS7 that shows the 427 Camaro injector covers definitely has a tri-Y design manifold or shorty header. Waaaay different than the cast iron manifolds that come on the LS3 and LSA cars. If that manifold/shorty header design makes it to production that will help tremendously over previous manifolds.
Those 3 things will make this LS7 more powerful than previous production LS7s. If they rate it at 505 and 470 it will be underrated.
2014 SS Sedan-daily driver
2013 Blue Ray1SS/1LE 1of20. "CAM ONLY" 475 RWHP/460 RWTQ 510 Race Engineering built/tuned/maintained