One of the debates that has popped up on Driver now and then is the CAI vs. stock air box debate. One side saying the stock air box is basically a CAI anyway so, no reason to waste your money and change to a true CAI. The other side saying the CAI would reduce air intake temps. I think I can bring an end to this debate with some preliminary test results.

I recently changed out my stock air box for a Nismo CAI. Prior to changing the stock box out, I took air intake temp readings at idle and at 45 MPH. Both readings were taken at the same locations each day on my daily commute over a period of a couple of weeks. Intake air temps were taken with my Blitz R Vit. I also recorded the outside air temp via the dash display at the same time. The attached chart has the preliminary results. I am still taking CAI temp readings so, I will update the chart during the next week.

At idle, it appears there is minimal difference between a CAI and the stock box. However, at speed the CAI reduces air intake temps by 7 to 15 degrees. Now, if this translates into HP/TQ is another question completely.

One additional item that I did notice, but not record, during the test is that the temp curve drop off after an idle condition is much steeper with the CAI then the stock box. Within seconds of accelerating, you are within 10 degrees of the outside air temp.

The chart is not complete yet but, the blue lines are the stock air box trend lines @ idle and @ 45 mph. The orange/red lines are the CAI trend lines @ idle and @ 45 mph. Once it is complete, I will update the chart and legends to post in the reviews section. I am interested in any feedback prior to my final update and posting of the chart.

Bottom line, it appears the CAI does as advertised and reduces air intake temps by 7 to 15 degrees at speed.

 

thats interesting to know, although i have a stillen air box. i never knew if CAIs actually did anything. good work

 

I have a K&N Typhoon intake, similiar to the nismo/aem/injen systems out there. FLFIRE, do you suffer from a slight unstable idle like I do? I have to correct the slight idle problem by using the "neffster technique" by turning on my AC which bumps my idle higher and makes the fluctuations less noticeable.

So far I am annoyed by the idle problem but my car seems to like the CAI in the cold weather. I'm interested in seeing how this mod translates to the dyno...want to dyno at next level or aerocomp next year? By that time i'll have my headers on like you.

 

i put a custom cold air on my car and did that plenum work i was saying, the plenum work is going to be bad *** once i can adjust my fuel accordingly, but now my idle is really messed up, and the car actually stalls if i am coming to a stop from a high rpm.


now also we know that the cold air is bringing in colder air, i have said that all along, how could they not work...


i am thinking that there might be something with the cold air that is bringing in too much cold air flow, vs the same flow with hotter air. i might not be explaining what i mean well, but i am thinking the problem actually lies in the computer being able to adjust accordingly.

 

When I was at Lokey, I had them bump my timing up by 2 degrees using the Consult II. No problems with the idle at stop light at all. I would suggest that you have them do this when you do the headers.

 

Before I started this test, I had the theory that as outside air/underhood temp increased, the worse the CAI would perform relative to the stock air box. However, the results appear to take me the opposite direction. Over the 35 degree temp range that I have measured, the CAI actually shows better performance, relative to the stock air box, as the outside/underhood temps rise. The reverse appears to be true: As outside air/underhood temps drop, the advantage of the CAI over the stock air box decreases.

 

It is on the "to do" list. However, I wanted to do a post dyno after installing the CAI, Cats and timing advance before I attempt something else.

 

I feel like buying Escobar's STillen box and giving it to FLFIRE so he can test out for a month....

Escobar? HAHAHAHA I still want them! Hurry up and superduper twin turbosupercharge your car lol

FLFIRE - thanks for doing this - the Florida peoples really need it!

Adrian

 

Tony
Nice write up! Have you noticed any off idle drivability changes with you CAI?
I just wonder how much a CAI changes the resonating air pluses in the whole intake plenum at low Rpm's, I personally like the idea of a cold air intake. Again nice write up! Pasta

 

This seems to be the most logical answer, anyway. The advantages would be at speed in any environment, but certainly greater in warmer weather than colder, though it seems the diameter of the CAI intake tubes is even bigger than the others.

This has been a great write-up.
I will be installing my JDM CAI next week along with the plenum spacer, and will get a dyno on that in early January...

 

wait till i get some pics up tomorrow of my custom CAI on the Z, it sits right in the front grill....

its pieced together with a sedan injen cold air and the stock Z pipe,


works perfect, it uses the stock air inlet hole...

and no matter what the air temp is outside, the air where the cold air is would be cooler, thats a given...

 

Just happened to think...

You're the only guy in the club that can't call your Z-Tube a mod... Hahahaha... j/k...