Not sure about using vacuum cleaner parts, but a true cold air intake can drop IAT's by about 80 degrees on these XJ's. I decided to build mine when my IAT's were reading 190- 195F on a hot summer day last year. After making a simple CAI,which draws air from in front of the driver's side wheel, my IAT was 110F with an ambient temp of 95F. Just have to remember to disconnect the last piece of tubing if I ever go through any mud/water, and that will leave my intake at same height as factory.

 

I pulled a flat scoop like this out of an oven galant this week. Maybe I can adapt it.

 

Whatever happened to the vacuum cleaner intake?

Even if the connections and hoses are slightly restrictive, I bet it can be run to the airbox which is still in its factory location and then your just getting MORE air.....

 

Eff it. Imma try something like that...

Gonna relocate the IAT then throw in some hose and run it somewhere that it'll take in cooler air..... and use my scanner to read the IAT before and after the add on hose