News today of Ford's rumored 7.3 L gas engine
Was at my dealership today and asked my sales advisor if he heard the rumors of the new 7.3 L v8 and he checked his sources while I waited and returned to say it's all bunk. No such engine is planned ...
Forum Discussion
With all the variable valve timing tech out there, and cylinder deactivation, packaging is simply friendlier with a pushrod motor. All that tech requires more space between the cams and valves, which requires much bigger valve covers on overhead motors, but can take up otherwise unused space in the valley of the pushrod motor. Also, variable valve actuators mean variable cam actuators can go away, and dual overhead cams aren't really needed anymore. Lastly, direct injection further improves cylinder management, making valve timing a little less critical.
FWIW - in the 2000s most of the European heavy diesel engine makers started making overhead cam diesel engines, to better control combustion cycles. As soon as High pressure fuel injection came into the scene, the overhead cam designs were made immediately obsolete, since injection control works even better.
And Groover is correct that lower operating RPMs is a new objective. It helps MDTs meet the new greenhouse gas emissions limits. That same standard is why the current 3-valve V10 was re-cammed and now has less peak HP, but more HP down low, and a lower overall operating RPM range.
FWIW - in the 2000s most of the European heavy diesel engine makers started making overhead cam diesel engines, to better control combustion cycles. As soon as High pressure fuel injection came into the scene, the overhead cam designs were made immediately obsolete, since injection control works even better.
And Groover is correct that lower operating RPMs is a new objective. It helps MDTs meet the new greenhouse gas emissions limits. That same standard is why the current 3-valve V10 was re-cammed and now has less peak HP, but more HP down low, and a lower overall operating RPM range.
