Thread: LRA Snorkel: my experiences.

Originally Posted by Lucus

You did read in my post that the change in vacum was at WOT? I am dubious about ram air effect and always have been. Feel free to do some testing on your own rangie and set what sort of pressures you have in front of the standard air intake and in side the airbox at 70kph and once you have some figures i will do that same with my car at 70kph drawing air through the snorkel. should be an interesting test. Obviously the bigger hole in the airbox will affect the result so i will make up a restrictor to reduce mine to the standard size if this pleases you.

What exactly do you mean by aerodynamic load?

My rangie is far from stock. Isuzu turbo diesel, homemade air filter housing with landcruiser element and intake at the front edge of the bonnet. My filter restriction gauge doesn't get past the first bar (2500Pa) with 20psi on a 4L engine sucking on it.
I've (breifly) considered a water gauge, but the risk of my engine sucking in the water didn't impress me.
That's why I'm interested in your results, see what the factory originally had going.
It's not necessary to make up a restrictor, at 70km/h cruise the throttle plate will be making all the restriction you need.

Aerodynamic load is the power required to push your vehicle through the air. It cubes with forward speed (twice as fast = 8 times as much power) and relates very well to air density. Colder (hence denser) air creates more resistance than hotter, thinner air.

I knwo this is an old post however its all very scientific. but colder, denser air can create a dramatic effect on performance and providing your car with this type of air (which a snorkel would, same as a cold air box) for eg. my XR8 ran half a second quicker on the quarter with the air pod sealed off from the engine n the air flowing around the front headlight into the box.

Originally Posted by maxpower

I knwo this is an old post however its all very scientific. but colder, denser air can create a dramatic effect on performance and providing your car with this type of air (which a snorkel would, same as a cold air box) for eg. my XR8 ran half a second quicker on the quarter with the air pod sealed off from the engine n the air flowing around the front headlight into the box.

It's well established that cold air improves performance. But that cold air increases your pumping losses when not at full throttle (petrol engines only). This increases fuel consumption.

Just another tradeoff really.