THE mid-mounted, oversquare Boxster engine is not exactly a reversed version of the similarly configured 911 engine, although obviously there is some commonality - for example the 78mm stroke crankshaft. A difference is the use of an oil chamber, rather than a separate oil tank as used in the 911, for a less complex design. Both cylinder heads are identical and breathe through plastic intake manifolds. Normally hidden entirely from view, the mid-mounted engine is accessible from underneath, from above, or from the front through special "service openings". The engine is cooled via a split radiator system, located ahead of the rear wheels on either side of the car.