Here is the update for the week of (
October 31, 2005). Normally I would wait till tommorow, but seeing as today is Halloween, I decided to do something a bit scary in Cadillac's history...
The L62 V8-6-4 engine 
The most notorious engine in the company's history appeared in 1981. The 425 had been reduced to 368 in³ (6.0 L) for the previous year's L61 Model Range but the improvement in mileage was minimal. Desperate for an engine powerful enough to move the immense Cadillac sedans, but efficient as well (especially in light of CAFE mileage standards), General Motors decided to make the fuel-injected 6.0 L V8 a variable displacement engine. General Motors subcontracted for the creation of the variable displacement technology to the Eaton Corporation, the end result being the L62 V8-6-4. This engine sequentially shut down pairs of cylinders when load was low, improving emissions and economy. The system was designed to reset to eight-cylinder operation when accelerating from rest or when the throttle was opened at cruising speeds. Cadillac hailed the L62 as a technological masterpiece, and made it standard equipment across almost the whole Cadillac line (the Seville retained its standard Oldsmobile-based 5.7 L diesel V8). The L62 proved troublesome, both mechanically and electronically, the latter due in part to computer technology that was much too slow for the task. The V8-6-4 departed from the main Cadillac line after the 1981 model year, but remained the standard engine, without the v8-6-4 feature, for factory Cadillac limousines for another four years (due mainly to the insufficient power of the HT4100 V8). No automaker attempted the same trick again until MB experimented with it on their V12 in the 1990s. It was not widely deployed until the 2004 DCXHemi and 2005 GM Generation IV small-block. All of these later systems work by deactivating a bank of cylinders, rather than opposing pairs.