It seems there are plenty out there operating under the assumption that engine bay temps are very hot compared to compressor outlet temps and therefore, insulating your intercooler piping is a good idea.  This blog will be short since math is hard to dispute.

First question:  How hot does it get under the hood?

Feel free to peruse this research paper on the underhood temps of several vehicles in several scenarios but I’ll summarize.

Idle @ 1000RPMs – 75C/167F (no convective heat transfer!)

Flat road at 60MPH – 30C/86F

Hill at 70MPH – 65C/149F

Second question: How hot does the compressor discharge air get?

The equation for such a thing is

Assumptions

Tin = 70F + 460 = 530 deg R

Pin = -5 psig + 14.7 = 14.2 psia

Pout = 14.5 psig + 14.7 = 29.2 psia

Pout/Pin (compression ratio) = 2.056

Assume an awesome compressor efficiency of 78%

So,

In conclusion,

a very efficient compressor running at a relatively low compression ratio outputs air that is significantly hotter than the test vehicles underhood temps in all scenarios by a minimum of 44 deg F.  Insulating this heat energy with silicone tubing instead of aluminum is a bad idea and can contribute to early onset “heat soak” of your intercooler and will most assuredly increase intake air temp post intercooler as well.