Statement: I ran a 10 minute datalog just now and the intake air temperature at 45 MPH was 38 degrees hotter than ambient air which was 76 degrees. My engine was breathing 114 degree air.
Comment: Not sure why anyone would do this test. A CAI is for HP. Which means you run it at WOT and not cruising around town.
Statement : Do you drive WOT in your neighborhood, on your commute?
Comment: Again, A CAI is used for more HP which will be seen at WOT. Doing cruising tests does not prove how effective a CAI is.
Statement: I'm no engineer, but that much hot air can't be good for performance. I did notice my mpg's being a little higher.
Comment: As a rule of thumb on V8 engines, every 30 degrees of lower ambient temps equates to approx. 1% more HP.
Statement: You will not lower your intake temperature with a CAI.
Comment: Never said you would. I posted that rule of thumb for the masses.
Statement: I will probably remove the intake and put the stock setup this afternoon.
Comment: Based on your testing, you are testing the effectiveness of a CAI the wrong way.
Statement: Perhaps but I tested under the conditions I drive daily. For comparison I did several 0 to 60 runs that were consistently slower than the stock box with drop in AEM. I tested in the morning with colder temperatures and in the evening. As expected the evening ones were the slowest.
Comment: You can test under conditions you drive but it's not the correct test for a CAI. A CAI kit is for increasing HP at WOT and not cruise.
Statement: Anyone interested in a CAI (HAI)?
Comment: Try WOT testing at the dragstrip or on a dyno. If the CAI is less restrictive, you will see an increase in air flow which will result in the following.
1. More air in, more fuel burned
Statement: Hotter air coming into the engine means less power produced (due to less air density) which will lower fuel consumption at the same RPM. In order to make more power you would need to operate at higher RPMs (near WOT or at WOT) vs a setup that provides cooler air.
Comment: At WOT air flow in the engine bay is moving and not as hot when compared to if you were sitting in traffic or cruising. Again, at WOT if the CAI is a good quality piece like the K&N or others like it, you will see a slight increase in HP and TQ thru out the curve at WOT.
2. Increased air intake noise because all the resonators were removed form the stk. intake setup.
Statement: I have owned 31 cars. I installed carbon fiber (true cold air intakes with ducts in front of the bumper) on an Audi and a BMW and the sound was noticeable but nice, beautiful growl. The Grand Cherokee setup sounded too loud for a slow hunk of metal.
Comment: You've owned way to many cars
. But let's be serious the Grand Cherokee is a SUV that weighs over 5000lbs. But trying to get more performance out of it isn't necessarily a bad thing.
3. More air, coupled with more fuel will equate to more HP. If the engine takes in more air it has to burn it. The increased air flow is not going to magically disappear.
Statement: You need to account for air density. I agree that at WOT you would probably gain some power since the air velocity is greater thus avoiding the air to heat up in the CAI tubes, etc., but no one drives WOT during their daily driving routine. I didn't see a benefit of keeping the CAI for my application.
Comment: Correct but saying it doesn't work for your driving routine gave the impression it doesn't work at WOT which could be confusing for people reading your post.
Thanks
Michael Plummer