Intake tract length.

Does the amount of energy that it takes an engine to "breathe" proportional in any way to the length of the intake tract?

To be clear, I am talking about the distance any given unit of air has to travel between the air filter and the MAF.

I'm thinking that the air pressure is constantly trying to equalize itself as the engine "sucks" in air, so the intake tract could be 100 feet long and the engine wouldn't "know".


But...
I don't know.
So... What's the deal?

Well here are my thoughts.....if you were running a marathon..and had your choice of breathing through a 1 foot long garden hose or a 50ft long garden hose with your nose clothes pinned..which would be easier to breathe through?


David

That seems like a monstrously generalized reply. If that were true, we would all be running the shortest intake runners and intake paths possible. I would say that intake length is just like any other "length" on an engine, such as intake runner length and exhaust length. Each certain length will work best for a certain range of RPM's and kill of power in other RPM's. Everything is a compromise, getting the perfect length is probably impossible.

One of my thoughts is that with a longer tube there will be less chance of reversion, and the pressure changes will be smoothed out through rpm changes. The shorter tube gives up less energy. (From friction with the sidewalls?)

The above replies seem to be confusing or mixing intake runner (head + intake manifold) and intake "track" (total distance from the filter to the plenum). The objective of designing the "track" is to minimize pressure loss. It isn't a matter of "energy".... its a matter of providing the lowest possible loss of pressure in the intake system, and hence the highest possible pressure for the air charge in the cylinders.

Longer pipes cause more pressure drop, but that could be offset by increasing the diameter. Bends cause pressure drop, sudden enlargements and contractions cause pressure drop. Its simply a matter of minimizing the loss, to maximize the pressure available to fill the cylinder.

Longer = more head loss.

hf=f·L/D·V^2/2g

What exactly are you trying to figure out this time Lame?

-Mindgame

I'm just wondering if certain packaging ideas would work.

I'm just wondering if certain packaging ideas would work.


Such as?

Such as?


Taking the business end of the air intake out of the engine compartment altogether.