IAT sensor placement - how bad is heat soak

I have a Supercharged 2GRFE without any charge cooling. This places the supercharge right in the valley, with a small manifold between it and the intake ports. I have my IAT on that manifold where it gets quite warm.

Can I rely on my IAT sensor to be giving me accurate temps? On 70(f) day I can expect to see IAT at 155(f). Today was a bit cooler and on the highway I saw 138 fairly consistently.

Hi. Knowing thermal efficiency of supercharger and intake air temperature you can calculate outlet air temperature and compair it with sensor reading to find out how accurate it is.