Disclaimer: The following is provided as a GUIDE ONLY, and neither myself nor Ozhonda take any responsibility for the outcomes of someone else doing the following. You follow these steps at your own risk!

Aim: to test whether a DIY CAI is of any benefit using a thermometer

test car: 2008 Accord 2.4 Auto

modifications:
Intake resonators removed - both the main one and the small one on intake arm.
Foglight cover removed.
Replaced with a PVC CAI from the foglight hole feeding the stock airbox and stock filter.
Small intake resonator replaced with a retic. 3/8inch cap from Bunnings.








pic of the small resonator replaced with retic plug. This is where I put the thermometer probe.



Results:

For a base reading: cold car, ambient temp reading 20.2C car thermometer reads 19C

car idling and warmed to operating temp. I did not start testing until the car had warmed up.
This simulates car waiting at traffic lights.
Time in minutes Temp degrees Celsius
0 ....................... 19.8
2 ....................... 20.5
4 ....................... 22.0
6 ....................... 22.8
8 ....................... 23.9

then I took the car for a drive. Back streets , no faster than 50km/h. Time adds on to before.
Time Temp
9...........23.2
10.........22.1
11.........21.3

Next I parked the car and turned off the engine. Reset time to zero
Time Temp
2...........24.7
3...........26.8
4...........29.2
5...........32.7

Now that there is a bit of heat soak happening, I went for another short drive.
Time continues from above.
Time Temp
6.........29.1
7.........25.5
8.........23.1
9.........21.9

The results show that the CAI is very effective in keeping intake temps close to ambient. Even at idle the temp rose only very slowly.
Unfortunately I did not test the stock setup with resonators in place so if someone is willing, it would be interesting to compare results.