Killing a Duramax L5P motor, 1004HP with stock internals. To get the 1004HP the Camshaft was changed and nothing else.
I have that engine on my 2020 2500HD, is a monster bone stock.
Warning, lots of math.
Part 14, Cam Science and Combustion Swirl... good info in Port, Timing, Valves, Injection, etc...
Part 15 of the series.