I agree the filter gets dirty easier but I have seen up to 12 hp increase by just removing the the cover

 

 

I've cut the top like SlowCar's, but I cut about an inch more on the left.


(SlowCar's photo)

 

As soon as my OpenPort cable comes next week, I'll do some legit testing & logging and report my results.

 

I'll be looking forward to the results shamelesscookie...will you be cutting out the side opposite the engine like jscbanks or the top?

 

OK! I'm happy to report that I've received my OpenPort cable and have begun logging.

Ambient temp today is 26°F, elevation 100', humidity 35%, Pressure 29.91".

I began with the airbox cover ON. I warmed the car up for 5 min at idle, then drove around town for 20m, then did several highway pulls for another 5 min. At this point, I had a good mix of driving for 30min. I then did the first RECORDED pull in 3rd gear on the highway, nice flat surface, from 3500rpm to 7250rpm.

Next, I drove casually for 5 min, removed the airbox cover, drove another 5m back down to the same highway point, and did another recorded 3rd gear pull...

I'll remind you, this is a stock-ECU IX with 5000mi on it. Mods are K&N drop-in, Forge UNOS MBC @ 20psi, Helix High Flow Cat, and Helix Cat Back.

Here are my results using EvoScan:

 

Why does your chart have 3563 RPM twice and then such a big jump from 3906 RPM to 7250 RPM?

Nice data, though. Thanks for the tests.

On your next tests, you can throw out the Air Volume. The request ID that is labeled as Air Volume on EvoScan isn't really air volume.


Eric

 

The 2nd value should be 3625, thanks for noting the error. Also, the big jump is seemingly due to no log entries between those values... I'm assuming I'm gonna have to do some more runs and see if I can get it to log between 4K and 7K... I'm using default EvoScan options, not sure if there's a way to improve logging speed.

What is "Air Volume" then, if not actually air volume ?

Thanks!

 

I just did the side cutout that jscbanks did...I'll report my findings and have some pics shortly.

 

I kept the Air box lid so outside air goes into the filter rather than engine bay air, and based on your results I'm glad I did. I appreciate you analysis.

When I first bought my car, I was concerned about the volume of air needed at high revs, and whether or not the stock plumbing could supply it. I conducted some but dyno tests and the car definitely responded better with the air box lid off.

So I decided to cut a hole in the right side (away from the motor) of the air box lid to see if it felt the same as it was without the lid. After several attempts I ended up with the right side completely removed. Now there is no difference in responsiveness (lid on or off), and I still get outside air routed to the filter. See below.

 

I'm considering doing this as well. Let us know how it turns out.

 

Have you guys ran into any issues with the mitsu dealership giving you problems with the lid being removed or cut out?

 

That shouldn't be a problem, but if you're worried about it just do what I did and order a second lid from mitsubishi...that way you can swap it out when you have the car in for service.
I am also curious if the JSCBanks cut increases BOV and turbo sound. Since there don't seem to be any downsides to that cut (yet), if it increases the sound than that alone might be a good reason to do it, even if the performance difference is minimal.

 

man i just pulled mine off too see( didnt wanna cut up the lid quite yet) and the car jumped up 1psi and help 18-19 to 7k usually only holds 16-17

 

I'm going to keep the top and just cut out the side like JSCBanks when I get off work tonight.