You can plumb the air intake to avoid the snokel, all the rage on T-bricks 240s, in case you have a similar set up in 740s. Just don't ford any streams in flood season, you don't want hydrolock. Then too, it is easy to calculate that the increased air intake for combustion, from a slight pressure increase that results form forward movement of the car, will be inconsequential to anything except your imagination. Snake oil, placebo, whatever, talking about the ram effect.