Forgive me if this is in the wrong thread.

I've seen on here lately people debating upon whether the factory air scoop under the hood functions normally or if it is just a great idea, but not so great in practice. I really want to keep this debate going, and by general consensus, see what the outcome is.

This is my experience. I took a test drive and wrote down some specs.

I didn't get the atmospheric air pressure, sorry. But this information should still be helpful.

At Idle, engine fully warmed up and in Closed Loop, the ambient air temperature of the engine bay was 151-152 degrees Fahrenheit. The intake air temperature was reading roughly 120 degrees Fahrenheit.

I took the car for a drive and at 45 miles per hour, the IAT was 102 degrees!

This was with a Short Ram intake and a heatshield around the filter (not the kind that wraps around the filter element, but an actual heatshield that seals off that part of the engine compartment as best it can.)

In my personal opinion, this would make it appear to me that the stock air scoop under the hood DOES in fact, function.

 

can you include pics? are you using a scan guage?

 

Pictures as in what?

I do have pictures of the air intake. Of the readout, I'm afraid not.

And I'm using an ELM327 OBD-2 to USB cable, with a Baud rate of 38400, with some freebie scanning software for PC.

 

doesnt matter if the scoop "helps" its still picking up heat from the "backside" of the engine, a completely new area would be nice, thats y i made a copy of the injen cold air when in short ram "mode"

 

Can't tell what you have done.
Did you install a tjermocouple i n the chamber on the intake side of the ait filter?
And then measure the ait temperature at idle, with the standard air intak, and then with the aftermarket air intake system?
we have, and found about 5 degress difference. The stock air intake is in a good place where the air is almost the ambient air temperature. The intake air system moves the intake location but doesn't change the inlet air temperature that much when your Fit is in motion and we found virtually no difference at speeds 60 mph and above. The factory did a pretty good job of locating the intake. Insulating the intake ducting helps some but a good sprsy foam did abbout as much good.
And just so you know, any effects of temperature such as 10F means a potential 540/550 fraction or about 2%. When you use the formula for those changes the temperature scale is 524F at freezing. The base is absolute zero. Pressure doesn't change much better. If youre running talledega it matters but not much on the street.

Most items, like the air intake, are designed to fit the available space and use prior components for less cost, not particularly for reliability or performance.

 

This is by no means scientific... But I did the DYI Short Ram Intake and there is a definite accumulation of dust/grime on the 'naked' filter that directly corresponds to the exit of the factory hood duct. I did purposely line up the filter to be right at the duct exit. Im convinced it really does work.

I can post pics of my 'grime evidence of functinoality' if youre interested.

 

i would like to see that because i am curious

does that grime come right of after a cleaning? would any happen to get into your filter?

 

with my air ram it makes circles of dirt where the ram is pointed at the filter. have u stuck ur hand out the window at 70 mph? the wind is strong but anyway any ram will help.

 

Its standard run-of-the-mill dust sort of thing precisely what the air filter is designed to stop from getting in the engine. When I take the filter off for cleaning I can knock most of it off and then the rest comes off when I use the K&N cleaning kit.

Basically just as the poster above stated, there is a circle of dirt on the SRI filter adjacent to the ram outlet. Nothing 'dangerous' to the engine, just standard road dust.

 

i think there is functionality of anything under the hood on a honda economy car. otherwise they would not put it there to save cost.

either it be for performance or reliablity there is a reason why it's there.

 

Agreed...they wouldn't spend money for no reason!

 

I always thought that scoop was to cool the ecu???

 

Agree completely. They have engineers working on these things all the time....it's their job. And they obviously do pretty well.

In this case the duct seems to me to have multiple functions...when the car is moving and there is a pressure difference. It takes cooler air and just drops it the general vicinity of the engine air intake horn with no direct connection. Since there is no direct connection, I'm guessing they have other functions in mind also. I had an '89 SHO with ducting from the left fenderwell area directly to the air cleaner intake box. Honda could have easily copied something like that if intake air were the only objective.

geo