SRI v. CAI...this time with actual data

[Darth Vader]

I bought a second filter, to turn my AEM CAI into an SRI, because I can and, I thought, wouldn't it be nice to have some actual data to finally answer the which one is better pissing match that has occurred here and elsewhere, in the past.

Here's the data I collected via Dashhawk and, my analysis:

Acceleration differences between CAI and SRI, negligible. I ran today, in 4th, 80 km/h to 140 km/h, at least 3 times each setup, all straight to WOT, same road, same environmental conditions. All turned in low to mid 6 second range. Couldn't really stretch it any harder/longer b/c of traffic and 6-7 degrees C making load cut a problem.

Interestingly, the SRI mode on the AEM is alot quieter than the Cobb SRI I had before.

Noticeably higher was the spike in underhood IAT when stopped. We're talking picking up 30 degrees in a minute here, as opposed to the ~5 on the CAI. Oddly, it still takes each the same time to return to it's base temp, about 10-15 seconds, despite the large temp difference. Temps while running were always over ambient with the SRI (~55 F), whereas the CAI would drop to indicated ambient or a touch below. The temp rise when stopped is not ideal at the track, definitely run hood up in staging if you have an SRI there.

So, all in all, the SRI has a tiny advantage in tip-in feel, no loss of acceleration, even up high and, a tendency to heat up when stopped. The CAI maintains its low IAT colossally longer than the SRI, which is an advantage at the track in reduced hassle in staging. Both measurably accelerate the same or as near as makes no difference.

 

[Sport6]

I run my mazdaspeed cold air as a short ram and have for over a year. I do it mainly just for the ease of access. I honestly have not even put the other section on, ever. I almost did when I installed my new headlight bulbs because I already had the bumper off but decided not to.

 

[MSMS3]

This is the kind of objective data that we need. Darth has done something solid and repeatable. Others can do the same thing and should be able to replicate his data because, IMHO, his testing method, including choice of rpm range and gear, reduce the likelihood of driver error. I think the translation from kph to mph, for those interested would work out to a 4th gear WOT run from 50 to 87 mph.

Guys will draw their own conclusions. The debate will not be over, but this really helps. To me, and it's just my own interpretation of the data, is that the differences are slight, probably do not amount to enough to favor one mode of operation over another, execpt in one small area which may not matter to many. To me the remaining significant difference is that it will take longer for the CAI to develop heat soak, but once it is soaked, they will perform equally.

His results are similar to my more simple test of temp rise in the engine compartment. I found that you can quickly get a 30 degree rise under the hood with the engine idling just a few minutes compared to ambient temp measured at the left front wheel well where the CAI is located. But that simple testing didn't say anything about how quickly the underhood temps would drop once the car was underway. Darth has helped us greatly with that.

Good work, Darth.