Hemi Camshaft Failure Mystery Explained
Somewhat of a mystery over the years has been these random roller camshaft failures in modern Hemis. Uncle Tony just made a video explaining his findings on the issue. If you are interested here ...
Forum Discussion
azdryheat wrote:
I've built a few engines in my time and this guy makes a whole lot of sense. Ain't no way I'd ever have a modern Hemi, which, BTW needs to be recalled and replaced. The original 426 Hemi was bullet proof. I don't know why Dodge didn't just repeat that design in a smaller engine.
Because the original Hemi was terribly inefficient. It would never make it on todays emissions targets.
The huge combustion chamber required big piston domes to get decent compression ratio's. Which also required lots of ignition advance to make sure you had enough time for a semi decent burn of the air fuel mixture.
It made power because it had tons of cylinder head flow for the time, due to the valve angles created by the hemispherical combustion chamber. These valve angles also created a physically huge engine that had nothing to do with the displacement.
Now we have modern engines that can get the same CFM with smaller ports and more efficient combustion chamber designs. All this leads to more power, cleaner burn, and more efficiency.
