Originally posted by AnGeLiCdEmOn108@Jul 6 2006, 10:27 AM
an interesting write up...
The M20 engine group was introduced in the late 70's in 2.0L and 2.3L sizes in the European model BMW 320/6 and 323. A later 520 sedan combined the fuel economy of the small six with the convenience of a 4 door sedan.
With consumer demand for more power, engine size was increased to 2.5 L, and in then new E30 chassis, electronic fuel injection powered the 323 and 325 versions. In the shadow of another fuel shortage BMW developed the ingenious 2.7 L eta engine which came to the U.S. in the 1983 528e and '84 325e. The engine was designed for minimum friction loss, highest possible fuel efficiency and maximum low rpm torque. In comparison, the 2.7L eta produces 170 lb/ft of torque at 3250 rpm, whereas the 2.8L 528i produces the same amount of torque but at 4500 rpm.
The 2.5 and 2.7L engines were strong and successful. In 1986 a BMW 325iS prepared by Linder with support from BMW Motorsport won the European Group A Championship and in the United States the Korman Autoworks 325e won the 24 Hours of Watkins Glen and the 1986 IMSA Endurance Driver and Manufacturers Championships. The Director of BMW Motorsport GmbH, Munich, Wolfgang Peter Flohr, wired a message of congratulations saying "The headline,'Korman's BMW Wins 24 Hour Race' is for BMW Motorsports GmbH a highlight which we tried to achieve in the United States for years and which goes without saying to your account only."
Everyone says they want more torque but horsepower still sells. By popular demand the 325iS came to the U.S. It had less torque (164 lb/ft @ 4300 rpm) but and increase of 41 horsepower at an enthusiasts 5800 rpm. It quickly became much more of a favorite than the low revving but efficient eta model. The 325iS made its own racing mark. In 1989 a 325iS entered by Le Team with engine and suspension by Korman Autoworks scored another win in the Watkins Glen 24 Hour Race. The primary competition R&D program for Korman Autoworks in 1993 was to develop the BMW 325iS for the SCCA IT series. The new model was an immediate front runner, overturning the previous dominance of the Nissan Z cars. The BMW won all but one race of the season, breaking lap records everywhere, and ran away with the Mid Atlantic SCCA ITS Championship!
