One of the most difficult tuning problems to overcome is the seemingly ever-present engine vacuum leak. Vacuum is an important component of the internal-combustion process because it controls basic ...

If you've taken a trip through the pits at a major drag race lately, you may have noticed that many of the Pro Stock, Gasser, Modified Production and Super Stock cars have begun sprouting unfamiliar ...

Question: why is vacuum so important on a vehicle? Answer: Vacuum is created when each piston moves down the cylinder with the intake valve open. It will change as the engine is running at different ...

It really was disappointing. The small-block Chevrolet rebuild went well and after the engine survived the flat tappet ...

If there is a classic bolt-on for a small-block Chevy, it has to be the aluminum intake manifold swap. This story is aimed at the first-time bolt-on artist, and we’ve chosen CHP’s My Generation ’87 ...

We may receive a commission on purchases made from links. A vacuum leak in a car occurs when there's an unintended opening in the vacuum system, which allows air to enter the engine. This disrupts the ...

The positive crankcase ventilation valve releases exhaust gas and unburned fuel from the engine block into the intake manifold. All engines allow some exhaust gases, unburned fuel and oil to “blow by” ...