Insulate cold air intake tube???

[67-LS1]

Just wondering if anyone insulates their air intake pipes? After going through the trouble of collecting cold air from outside the engine compartment most systems I’ve seen run an aluminum tube through the engine compartment, near the radiator, headers, etc.
Wouldn't it make sense to insulate the tubing?

[GoodysGotaCuda]

I've looked into this recently. Yes, insulating it with some sort of aluminum backed foam would be one of the best solutions.


I am planning on running a carbon fiber tube, which is many times less thermally conductive than aluminum. If necessary, I'll coat it with Lizard Skin ceramic coating, or something similar. While the performance of the aluminum insulation is pretty good, it sure is ugly and hard to look at.

The other part of this equation is the air doesn't spend much time air intake tube unless you are at low rpm/low throttle opening. The thermal exchange takes time to occur. So when you do want "power", you're likely up in the revs and the temperature of the tubing doesn't matter too much.

[jlcustomz]

As stated above tubing temps not the most critical thing with air moving through it. Where the air comes from is the most critical. I got mine coming in through a custom opening in front of hood , which I understand to be about the best spot of air intake.

[67-LS1]

Mine is an everyday car so mostly in traffic, normal driving, etc. Probably not critical but measurable?

[130fe]

I guess you could see what your IAT temps are depending on where that sensor is located.

[dhutton]

You would be surprised how much the IAT rises when sitting idling. I have monitored it and it’s 40 degrees or more if I remember right. That was with a plastic Airaid tube. I would expect more with aluminum.

Don

[anguilla1980]

On my 92, I switched from the solid IAT to an open IAT about 19 years ago for tuning purposes. It updates MUCH faster than a solid and will not report incorrectly based on the heat soak of the aluminium intake it's threaded into. I've seen swings of 80f+ easily in traffic during the summer. There is a reason OE uses plastic, less thermally condutive than aluminum, as mentioned. I swapped the factory intake for an SLP intake which was also plastic and looks nearly the same, BUT bolted to the inside of the fender to seal off the engine bay. That made a TREMNDOUS difference in peak IAC. Once I would transition from the stop and go traffic onto the freeway, the IAC temp would go down very quickly. Before when it would suck in engien bay heat, it cooled down slower for sure.

Bottom line, long as the intake tract material is not metal and a plastic or CF, the key is to have the element totally sealed off from the engine bay heat to outside air only. Any other heroics I think are academic because also as mentioned, the airspeed through the intake tract at speed, let alone half to full throttle, is a lot.

[ULTM8Z]

On my 92, I switched from the solid IAT to an open IAT about 19 years ago for tuning purposes. It updates MUCH faster than a solid and will not report incorrectly based on the heat soak of the aluminium intake it's threaded into. I've seen swings of 80f+ easily in traffic during the summer. There is a reason OE uses plastic, less thermally condutive than aluminum, as mentioned. I swapped the factory intake for an SLP intake which was also plastic and looks nearly the same, BUT bolted to the inside of the fender to seal off the engine bay. That made a TREMNDOUS difference in peak IAC. Once I would transition from the stop and go traffic onto the freeway, the IAC temp would go down very quickly. Before when it would suck in engien bay heat, it cooled down slower for sure.

Bottom line, long as the intake tract material is not metal and a plastic or CF, the key is to have the element totally sealed off from the engine bay heat to outside air only. Any other heroics I think are academic because also as mentioned, the airspeed through the intake tract at speed, let alone half to full throttle, is a lot.

+1

I have my air filter completely outside the engine compartment and relocated the IAT sensor to the same location as the filter on the premise that the air temp won't significantly change between that point and the throttle body (i.e., the sensor isn't "lying" to the ECM about the air temp). With my composite air tube, that's likely an accurate assumption.

Like anquilla said, it made a HUGE difference in tuneability for consistency in fueling as well as never having the car feel sluggish when it gets hot. IAT temps react extremely quick to the car moving or standing still, and even when standing still in traffic, the IAT temps never get more than ~10-15 deg over ambient.

[67-LS1]

I decided to insulate mine.