As with most things in life, it’s the details that make the difference. You might not think that a measly degree here or there could make more horsepower when it comes to a valve job, but there’s ...

'Breathe in . . . breathe out. Simple respiration is what keeps us alive, and your engine is no different. On a normally aspirated engine, atmospheric pressure pushes air in through the carb, intake ...

Modern engines are cleaner and more efficient than the ones you grew up with, yet many drivers are discovering a new headache: stubborn carbon crust building up on intake valves. Understanding why ...

For Part I, covering the new combustion system, direct injection, and active fuel management: click here. For Part III, covering the block, crankshaft and lubrication systems: click here. Continuing ...

Last month we showed what gains were available from three aftermarket Three-Valve intake manifolds in naturally aspirated trim. This month we're going to try the same three intakes, only now we'll see ...