Ever since installing an engine oil cooler, my intake temps increased by about 5-8 degrees F. While cruising on the highway my IAT was about 14 degrees above ambient and about 24 above ambient while city driving.
I modified the stock intake boxes to draw air from inside the front of the nose instead of from above the radiator and oil cooler. Now IAT is 5 degrees F above ambient on the highway and 8 degrees above ambient in city driving.
This has made a huge difference in responsiveness on hot days, especially off the line in city driving. The nose area doesn't fill up with hot air as much while sitting at a red light or in slow moving traffic. I'll post a pic when I get home.
Edit: pictures