Want some insight on this if possible...

Outside ambient temp showed 75-78 deg F.

IATs while cruising sat right at 100 deg F and then up to 107 deg F at idle (didnt idle long, it kept climbing)... a FULL twenty two degree swing at LEAST. (using my cortex to read iat)

Is this normal for the factory IATs?

How much does the 20 deg F difference make on overall performance... what does it translate to with engine timing and horsepower.

I know this is a tough question to answer... but what sort of daily driving difference can I expect with one of the HSRK or IAT-R kits?

I could be way off here, but that doesn't seem to crazy if you dont' have a CAI. Temperatures under the hood (where the incoming is coming from) are going to be alot higher than outside temperature.

That is about right and even with a CAI would be as close if not maybe a little higher.

I was reading 120ish with hp tuners after the car sat in the garage on a recent log and right at 100 after driving for a bit and it was about 80 out that day.

relocating it does wonders on temp and cool down time

My IAT would often read +50° over AAT with both the stock air-box, and RF CAI. I recently added a HSRK, and the IAT temps are usually around 90-100° (compared to 130°+) regardless of AAT. The HSRK certainly helps keep the IAT down.

Not sure how much this helps horsepower, but it does not hurt.

It affects horsepower in the fact that the higher the iat temps are the more timing the ecm is pulling out per the iat timing reduction tables.

There are 2 ways to address, add in a hsrk kit or adjust the tables so the timing does not pull out as aggressive. I personally just modify my iat tables and insulate the maf better on my cars.