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Old 01-17-2005, 03:08 PM
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Great job Willys! Just one note -- not all dual overhead cam engines have hemispherical combustion chambers. They can be "pent roof" (like a house roof). That said, I do understand that the OHC arrangement is a must for Hemi chambers.

Supercharging is pressurizing the intake air, regardless of how it is done. When people refer to "supercharging", however, they usually mean a belt driven type. A turbo charger (techincally a turbosupercharger) is exhaust driven but does the same thing. There are two major types of belt driven superchargers: the big Rootes type "blowers" that were originally designed for diesel engines, and centrifugal, which are smaller and sit beside the engine. In essence the centrifugal supercharger is a belt driven turbocharger. It's more to it than that, but the basic design is similar. Most centrifugals have a gear drive to spin them up faster than possible with direct belt drive. There is also a screw type blower that looks much like a Rootes type, but uses two big "screws" to pull air in and compress it. The Rootes blower uses two slightly twisted, interconnecting "lobes". I'm sure you can find some pics on the net, likely at the link posted previously.

Take a look at This is a turbocharger turbine with a belt drive adapter. Note the small diameter pulley, needed to get the ting up to speed. I don't know what diameter pulley is used on the crank, probably the typical AC compressor size. You can't connect a pulley directly to the turbo shaft as the bearings aren't designed for the side load. So an adapter with heavy enough bearings is used in front of the turbine.
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