techfun89 writes "The Sea Lion is the world's fastest amphibious "land speed" vehicle and you can buy it for $259,500 (USD).
The Sea Lion's designer is calling it an Amphibious World Speed Record Competition Vehicle. Designed to set world records on water and land, it comes in at 125 mph on land, which may seem unimpressive, but off road is where it makes its mark. It can reach 60 mph on water. The water speed is limited by horse power. They are currently using a Mazda Rotary 13b (1974 — smog exempt) engine.
The vehicle is mostly TIG welded 5052 Aluminum constructed materials from CNC plasma burned shapes and other CNC milled components. It has an integrated monocoque welded uni-body center section. The Sea Lion also has removable side pods which are used for floatation and cargo, along with removable fenders on the front and rear."
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