into the face of the driver and passengers. From the 1970s forward, sandrail builders continued to develop the delicate balance between weight and power. Body style When it comes to serious sand dunes, most off-road vehicles including those with four wheel drive are relatively top heavy and can only safely climb or descend steep hills with a mostly perpendicular approach to inclines or downhills. In the case of driving up a steep sand dune, many would simply "dig-in" and get stuck. Sandrails are ultra lightweight vehicles often weighing in at 800 and 1500 pounds (≈363 and ≈680 kg). They typically use high flotation smooth or farm implement front tires and special rear paddle tires, allowing it to skim over the surface of the sand without getting stuck. A sandrail has a low center of gravity, permitting it to make tight turns even on the face of a sand dune. Sandrail frames are built from a tubular space frame chassis that incorporates an integrated roll cage. The distinction between a sandrail and dune buggy or sand car is that the sandrail will rarely have windows, doors, fenders, or full body panels. The sandrail will also be a lighter weight vehicle compared to the sandcar. On most sandrails, the engine is typically at the rear. Some sandrails also use a mid-engine configuration. This design offers favorable weight distribution and traction, which is very desirable for dune "hill-climbing". Engines and fuel Originally becoming popular in the 1960s, sandrails used lightweight air-cooled engines like the Volkswagen engine from the VW Beetle and Porsche (~200 pounds) or the Chevrolet Corvair, Mitsubishi Minica and Cosworth DFV (~350 pounds). Because of the availability of affordable parts, the Volkswagen engine continues to be the mainstay of many sandrails today. At some point in the late 1970s in the wake of the Ford Pinto product liability cases, the first alternative engine was sourced from the Pinto, primarily the 2.0L and 2.3L. More recently, some enthusiasts have turned to lighter weight water-cooled engines such as the Subaru boxer or GM Ecotec engines. The need for more power comes from necessity and desire when driving in steep sand dunes. This has driven sandrail engine builders to add performance features to engines such as the stock (24 to 50 horse power) Volkswagen engine. These include: larger pistons, turbochargers, dual racing carburetors, fuel injection, and high performance cylinder heads. Some performance engines can