For those of you that would like to learn a bit more about the Shovelhead Engine, this article will teach you the basics. For starters, the shovelhead engine is a type of V-twin engine that was manufactured by the Harley Davidson Motorcycle Company between 1966 and 1985. The design for the shovel head engine was developed based on the design of the Panhead engine. The difference is that the shovelhead engine includes more powerful cylinders and pistons as well as a modified look.
What some of you may not know is that the shovelhead engine received its name from the unique look of the engine's rocker box covers. These covers bear a resemblance to the heads of coal shovels. That is how the name "shovel head" came into existence...
Back in the mid-sixties, the Panhead engine was initially developed to fit Sportster choppers. As time went on, the Panhead lost its attraction and went out of style due to the fact that Harley Davidson began developing bikes that required more horsepower.
Around that same time, the shovel-head engines entered the scene with newly designed top ends that were created to give you more acceleration and power. Unfortunately, many motorcycle experts now say that the weight of the new shovel head engine detracted from the speed and power of certain models in the sixties. In fact, the shovel head engine was originally designed as an engine for an outboard motor (a motor for boats), but it did not function in water or in moist air.
In the 1970's, minor changes were made to the shovel head engines that helped fix some of the problems demonstrated by the weight of the sixties shovel head model. However, most Harley specialists would say that even these revisions did not quite catch the shovelhead "up to speed." This was mainly due to that fact that Harley Davidson had to stick by government regulations that basically said choppers could not have more than a top speed of 90 miles per hour.
Another interesting tidbit of info is that if the engine came with a feature called the FLH Electra-Glide Package, it was identified as a shovel head engine for police bikes. Sometimes this feature is called the Police Option. It definitely made it easier for Police to run cars off the road.
Additionally, The FLH Electra-Glide package also enabled the engine to turn over longer while the machine was in idle. Unfortunately, it made for a heavy bike that was not easy for the average rider to maneuver or brake instantly. It's very hard to find a Harley shovelhead engine with the original FLH Electra-Glide package. It's very rare and is prized by motorcycle and chopper part collectors.