More info on Snorkels, this one a test on a dyno, not the open road.
http://www.lcool.org/technical/120_s...rformance.html
"A straight forward test is to see the affect of a snorkel on engine performance under the worst possible conditions. That is, stationary on a chassis dyno. This will highlight any deficiency of the snorkel system when compared to standard because the test is conducted with zero air velocity (hence zero positive pressure over atmospheric conditions) to the snorkel air ram. Much like holding your open hand out of the window of a fast moving car, the air ram takes advantage of that additional air flow to move the point of zero positive pressure further inside the snorkel body, thus improving air flow further.
An automatic V6 Grande was used as the test vehicle and 3 full throttle power runs (in 2nd gear) were conducted on the dyno to determine the standard power at the wheels. The best power and torque curve was plotted below (124.7 kW). A Safari SS186HF snorkel was fitted to the Grande and another 3 power runs were conducted. In this case, the lowest power curve was plotted over the standard power curve (127.2 kW).
The result was a worst case net gain of 2.5 kW at the wheels or 2% improvement. This indicates that the Safari SS186HF snorkel delivers a less restrictive air inlet than standard. This also suggests that at speed, the improvement will be greater, however it is all but impossible to conduct accurate and repeatable tests when the vehicle is speeding along. None the less, on the 120 Series, the improvement in engine performance is real and quantifiable under worst case conditions."
