Parts

A 4-door power valve provides more aggressive fuel enrichment due to its four fuel enrichment doors, making it ideal for high-performance and racing applications. In contrast, a 2-door power valve delivers a more controlled and gradual fuel flow, making it better suited for daily drivers and street vehicles where fuel efficiency is a priority. Power … Read more

The 4.5 and 6.5 power valves differ in the vacuum level at which they open, with the 4.5 opening at 4.5 in-Hg and the 6.5 at 6.5 in-Hg. The 4.5 valve is better suited for high-performance engines with lower vacuum, like those with aggressive camshafts, while the 6.5 is ideal for street engines with higher … Read more