There is no question that the DOHC 5.0L Coyote engine has taken Mustang performance to new levels, and the spotlight, but if you have a Three-Valve 4.6L, there are still a lot of performance options ...

For mild street engines, stock valve springs are more than adequate. But if you've screwed in a big bumpstick for strip-banging or banzai runnin', then pay attention. Our plan was simple: Install a ...

During one of our never-ending technical discussions, Jim Grubbs at Jim Grubbs Motorsports (JGM) suggested that we take a look at the flow difference between 30- and 45-degree valve seats. While ...

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 ...