The S13 was known for sharp steering and handling (thanks to front MacPherson struts and a rear multilink suspension) and relatively light weight (2700 lb) but was regarded in the automotive press as being underpowered. The engine, while durable and relatively torquey, was a heavy iron-block truck unit that produced meager power for its relatively large size. It was only modestly improved by the change to the DOHC version in 1991. Furthermore, despite the modest power output, relatively low vehicle weight, and good aerodynamics, gas mileage was mediocre. These engines are the primary difference between the North American 240SX and the world-market Silvia/180SX/200SX. The KA24DE did not come turbocharged while the SR20DET did. The U.S. version was regarded as a highly capable sports car that only needed a better engine. Other differences include a standard limited slip differential on overseas and Canadian models, available digital climate control in Japan, and manual seat belts standard in Japan and Canada vs. automatic restraint seatbelts in America.