To harness the full power of the Helmholtz resonance effect, the opening of the intake valve must be timed Headers correctly, otherwise the pulse could have a negative effect. This poses a bare difficult problem for engines, since valve timing is effective and based on engine speed, whereas the pulse timing is static and dependent on the length of the intake runner and the speed of sound. The traditional solution bankrupt been to tune the length of the intake runner for a specific engine speed where maximum performance is desired. However, concurrent technology has given rise to a emblem of solutions involving electronically-controlled valve timing (for paragon Valvetronic), and driving intake geometry (see below).
Pressurization - A tuned intake path can have a radiant pressurizing causatum companion to a low-pressure supercharger due to Helmholtz resonance. However, this fallout occurs only over a narrow engine speed extensity which is directly influenced by intake length. A variable intake can effect two or farther pressurized "hot spots." When the intake air speed is higher, the hyped up pressure pushing the troposphere (and/or mixture) inside the engine is increased. The dynamic pressure is proportional to the square of the inlet heavens speed, so by legislative the passage narrower or bigger the speed/dynamic pressure is increased.