Originally Posted by
harry
thanks ron, i did think mr lr had spent a lot of time researching this as it is really a small opening at the throat of the venturi.
err, mines hacked off to fit a battery, after long hours thinking about it, also i temp tested intake air in the box and in the inlet to sort the venturi differences, not much, but the engine does get very hot air, which probably has something to do with emissions - a snorkle would improve the intake temps, and therefore improve economy 'perhaps' by allowing more air in. but this is also flawed thinking, as the colder the air, the more the oxygen content, so the more fuel we can mix with it - all good so far, until that air gets sensed by the 'mass air flow meter' which has been set to give predetermined values at the factory.
so no gain.
as for those thinking about the ram effect of snorkels - forget it!
170 mph impact air [ram] has the potential to increase the manifold pressure by 1 inch of mercury.
or to make it a bit simpler -
still air, 60 mph [you work out the kph, i'm not doing it all for you]
pressure increase of air - psi - .065
in hg - .128
in h2o - 1.774
and then you have to factor in the air temp and humidity,
ram air in a truck is not an issue, it doesn't do diddly sqat!!!!!!!!!!!