Stick your head too close to an old car's exhaust, and we're willing to be dollars to donuts that you'll start coughing. It turns out that vehicle exhaust isn't just bad for you until the air clears.

Here’s a hack that’s been around since the very start of the hot rod movement. Car exhaust flame throwers work by interrupting the spark to the engine. This dumps raw fuel into the exhaust system.

It funnels exhaust gases from all the cylinders and routes them to the car’s catalytic converter. V-type engines have a separate manifold for each cylinder bank. A leak in the exhaust manifold ...