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Old 05-21-2013, 08:01 PM   #11
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Originally Posted by dyn085 View Post
I understand the Newmission mod and the comparison to the snorkel-delete; I've dyno-tested both. I even created a fiberglass scoop and used aircraft ducting (the radiator hose is better, imho). I actually have my Newmission'ed box for sale in the BST area, which led to some pictures and discussion of my scoop.

The 'vacuum bottle' is the OEM resonator. It is designed to act as a shock absorber for the air box. It absorbs the excess energy in air pulsations to reduce resonance, which is noticed with its removal. If you were trying to remove 'annoying sound', then reinstalling it should have been the first step.

What I was alluding to in my other post is that the snorkel has no bearing on NVH. It does, however, restrict air flowing into the runners. The purpose of it's removal is not to make it a 'ram air' intake; it is removed for the sake of allowing the air an easier, unrestricted path into the runners. If you were wanting to turn it into a 'ram air' setup, you would have to fabricate a scoop that was a larger diameter than the opening in the radiator support for the runners.

Your mention of the throttle body is correct to a small degree, but make sure that you pay attention to the fact that your MAF sensor is significantly larger. Do some research into Bernoulli's Principle for a better understanding of why. That should give you a little better understanding.

You are on the correct path for testing, and I'm glad that what you have is working for you. Different peoples' commutes result in different numbers in reference to MPG's and mods. I did as much dyno work as I could to prove/disprove the 'cheap' mods, but unfortunately power numbers do not have a direct relation to mileage. What works for some based on their circumstances doesn't work for others. The only thing that's practically guaranteed on everyone's car when it comes to cheap mods is the snorkel delete/drop-in filter.
I stand corrected on the purpose of the small vacuum vessel at the bottom of the air box. Replacing it would not accomplish anything with the Newmission mod. which I want to keep.

I do now wonder what's the purpose of the intake snorkel? Do the jet-like holes act as venturi-- or is the thing just some glorified plumbing? Ford went to a lot of trouble designing it.

Afraid I see no connection to Bernoulli's Principal in what I was talking about. To my way of thinking the amount of air entering the intake will be the same if the air supplied does not create vacuum inside the air box. The only restriction being the air filter itself, which replacing with the K & N helps somewhat. I didn't mean to reference the relationship between air velocity/ air pressure/orifice size.

Replacing the snorkel tube (the part with the holes) did seem to quiet the engine to me. And my MPGs continue to rise. Of course washing the car makes it go faster!
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