Cold air is good. Hot air is bad. Every gearhead, young and old, is familiar with this line of thinking. We buy hoodscoops, cold-air intakes, and all other manner of contraptions to help feed our ...

So what do you do when you've built your motor, strapped on the biggest turbo you can tolerate and basically tuned your forced-induction car to the teeth-but you still want more power? More boost ...

The idea of injecting an incompressible, incombustible liquid into an engine appears, upon initial consideration, like an inadvisable move. After all, those who have watched a driver tackle deep water ...

Diesel particulate filters are a double-edged sword. They allow manufacturers to meet strict modern emissions requirements and build trucks with world-record torque output, but that comes at the price ...