Pushrod engines typically use two valves per cylinder, and as a result this engine style is often mocked when used in modern vehicles.
source/image: Engineering Explained
Fewer, larger valves results in more reciprocating mass which can lead to valve float, and less airflow at high RPM from the reduced area of the valve openings versus four valves.
So why are companies like Dodge still making Hemi engines, and Chevy still making LS engines, both of which are two-valve pushrod setups?Check out the video for five detailed reasons why these engines are still made.
Well, simply put, pushrod (OHV) engines have quite a few advantages over their DOHC counterparts. Whether it’s the size and compactness of the engine, the simplicity, or the cost, there are real performance benefits to using a two-valve, single cam V engine. As the saying goes, if it ain’t broke.