So I drilled
Just a thought. Looking at the fins on the intake, it looks like they were put there as a design consideration (i.e. after a mold flow analysis) to help the intake cool correctly without warping. This allows less plastic (and less $$$) to be used in making the intake.
The cost savings is not really a consideration for the F-sport intake which could be why they do not have them.
The cost savings is not really a consideration for the F-sport intake which could be why they do not have them.
Driver
Joined: Feb 2011
Posts: 191
Likes: 0
From: VA
So yes, I drilled...but then I stuffed it with a modified check valve. My new Joe-z pipe made me to do it.... 
I did this mostly out of fun, but I also wanted to try and limit the amount of heat making it's way in with a large new opening. The valve only opens when there is enough vacuum pressure applied from the intake. It remains closed all other times. Figured this would allow the nice sound out while allowing (possibly hot) air in, but only when at WOT, or there about. Need to test to see how much pressure/rpm is required to open it. I also wanted to maintain pressure within the box as well in hopes to overcome any possible lag in throttle response with the new opening.
Inside:
Outside:
I did this mostly out of fun, but I also wanted to try and limit the amount of heat making it's way in with a large new opening. The valve only opens when there is enough vacuum pressure applied from the intake. It remains closed all other times. Figured this would allow the nice sound out while allowing (possibly hot) air in, but only when at WOT, or there about. Need to test to see how much pressure/rpm is required to open it. I also wanted to maintain pressure within the box as well in hopes to overcome any possible lag in throttle response with the new opening.
Inside:
Outside:
Driver
Joined: Feb 2011
Posts: 191
Likes: 0
From: VA
Thanks ApokC! My initial idea was taken from the isf intake which opens electronically based on rpm. Mine's obviously not as accurate since it's based on vacuum pressure which grows at higher rpm's. I originally had a panel that was more spring loaded that would open and close with the vacuum pressure. But then I wanted to try and build a cold air intake using the scoops in the front lower grille. So this new check valve concept was supposed to connect to a snazzy new (fsport blue) tube that connected into one of the lower scoops. So once installed the check valve, I connected the hose to it and went to connect it to the scoop. Unfortunately, the scoops lead to the wheel well. FAIL 
In any event, was mostly just having fun building something unique that gave me the added intake growl while maintaining the overall design integrity of the original box.
As far as Lobuxracer’s comment, I seem to recall him discussing 06isDriver’s custom cold air intake where he was pointing to better gas mileage in summer vs. winter(hot air vs cold air)? Is that what you’re referring to? If so, there are a lot of other things to consider. The biggest of which is, gas is a completely different blend in the summer and contains nearly 2% more energy. Secondly, oil viscosity is affected by heat. Heat reduces the viscosity, making it thinner and reduces drag and increases efficiency. There’s also tire pressure and many other elements that come into play. However, I think his MAIN point was, that any increased performance 06isDriver might see in his cold air intake would be offset by the drain on the alternator.
Long story short, the impact on the opening of the throttle with hot air(open box) vs. having a valve in place will not be measurable at low rpm’s. Especially since as the throttle needs to open, it increases the vacuum pressure which opens the check valve.
In any event, was mostly just having fun building something unique that gave me the added intake growl while maintaining the overall design integrity of the original box.
As far as Lobuxracer’s comment, I seem to recall him discussing 06isDriver’s custom cold air intake where he was pointing to better gas mileage in summer vs. winter(hot air vs cold air)? Is that what you’re referring to? If so, there are a lot of other things to consider. The biggest of which is, gas is a completely different blend in the summer and contains nearly 2% more energy. Secondly, oil viscosity is affected by heat. Heat reduces the viscosity, making it thinner and reduces drag and increases efficiency. There’s also tire pressure and many other elements that come into play. However, I think his MAIN point was, that any increased performance 06isDriver might see in his cold air intake would be offset by the drain on the alternator.
Long story short, the impact on the opening of the throttle with hot air(open box) vs. having a valve in place will not be measurable at low rpm’s. Especially since as the throttle needs to open, it increases the vacuum pressure which opens the check valve.
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From: Under an IS F since 2008
Actually, I think it's the other way around. 
He created a design similar to (or better than) the F-Sport Box...
The bonus is that the check valve hole extra air, will only come in at WOT...
Which "in my opinion", is more than likely better than a hole open all the time..
Joe Z
He created a design similar to (or better than) the F-Sport Box...
The bonus is that the check valve hole extra air, will only come in at WOT...
Which "in my opinion", is more than likely better than a hole open all the time..
Joe Z
Last edited by Joe Z; May 20, 2011 at 11:14 AM.
The reason for the extra hole in the airbox on the F-sport intake is so it makes more noise.
A surprising number of folks who drop a ton of cash on aftermarket parts want more noise.
See also some of the crazy-expensive exhaust systems that don't add much else... or any of the open-element intakes that suck in hot air but sure are loud.
A surprising number of folks who drop a ton of cash on aftermarket parts want more noise.
See also some of the crazy-expensive exhaust systems that don't add much else... or any of the open-element intakes that suck in hot air but sure are loud.
Last edited by mjh09e; May 24, 2011 at 11:32 AM.
