That’s why. Exactly why. They don’t make any more power. Also, consider tooling. When machining aluminum it’s much easier on tooling than cast iron. So the OEM’s love to use aluminum because it saves on drills, taps and other tooling.
The number one reason why guys can’t run compression is coolant temp. 180 should be the maximum coolant temp on any performance engine. Ever.
Guys running above that are wasting power and causing issues like run on.
