Intake manifold with 19mm passage by Top Racing for Minarelli engines. By the slightly longer intake path better filling is achieved at lower speeds. That makes this especially useful at intake when only slightly tuned (up to 70cc Sport) or original pristine engines. The suction accelerates the gas column and produces the higher speed with more air. However, this process is somewhat disadvantageous in high end racing and tuning, since the motors rotate much higher speed and less time is available for filling. For these engines, we recommend using shorter intake.