GM Releases 2013 bogus HP ratings at PRI show

[Andrew Hill]

Originally Posted by Andrew Hill

Here's all 3 listed with flow numbers
http://www.thefordsource.com/store/p...-6049-Z304.pdf

"Intake port volume as cast: 204 cc"
"Exhaust port volume as cast 85 cc"

In the Stock/Super Stock Cylinder Heads Volume list, both Z304D and Z304DA are listed with:
Intake CC's Max: 230
Exhaust CC's Max: 91

All have CNC'd combustion chambers, M-6049-Z304P has CNC ports as well.

Also, the engine blueprint guide has a 56 cc combustion chamber, while a 63 cc one is listed in the specs. What's the deal with that?

How can I go about getting an extra 26 cc's on the intake and 6 on the exhaust approved?

So does anyone have any answers for this? Where did the extra cc's come from if they're not ported?