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 ...

'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 ...