Thread: FS: ~~~ BDJ Duel Intake - $300 OBO ~~~
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Old Jun 13, 2011 | 11:05 AM
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onehundred80
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Default Re: FS: ~~~ BDJ Duel Intake - $300 OBO ~~~
Originally Posted by Holycrap
Air will be available instantly with the short ram. Air has to travel less distance to reach the throttlebody. in the midrange it should start to even out as the colder air will help more, but remember its taking more time and effort for the cold air to reach the engine as compared to the warmer air thats effortlessly ingested. when there is ALOT of air needed thats when the cold air should start performing better than the short ram. put it this way. try to breath in through a straw.... now cut it in half, and cut it in hlaf, again. The shorter the straw/intake becomes the easier it will be to breath.
We don't mention ram air on here or devils horns for that matter.
Air rushes in an attempt to balance pressure, always has and always will. The downward stroke of the piston would create a vacuum but for the valve opening and nature abhors a vacuum so the air rushes in.
The size of the pipe will affect the air drawn in, the faster the air is needed the more the pipe affects the air speed, particularly the boundary layer that is against the pipe walls.
The faster the air flows the thinner the boundary layer. The effect can be seen when you have rain drops on your hood, at slower speeds the drops just idly move toward the windshield as the speed increases you will see them move faster and faster as the boundary layer gets thinner.
You may have noticed bugs crawling around the windshield and wondered how they stayed there at such a speed, its because they are in the boundary layer.
If the pipe supplies enough air at full throttle less than full throttle will have plenty.
The biggest losses in air flow are at the filter as the air has to pass through thousands of small holes and each hole applies a loss. The smaller the hole the greater the loss - period. Larger filters with the same size holes are therefore better. So keep those filters clean.
Doubling the length of intake in this case would have little affect on the air supply and cooler air would more than offset any air losses due to the boundary layer.
If the outside temperature rose close to the under hood temperature then you may have a point, but by that time the engine would have overheated anyway.