Climatizer hole? And excessive heat

[DobbM]

Hello all. I'm trying to cool off the cabin. I checked the butterfly vents and they are fine. But as I was under the passenger side dash I was looking at the heater box/core area. To the left side is a hole, 2" x 1.25-ish inches and about 4 inches deep. The hole looks intensional, but not factory (super smooth edges, etc.). Was it the place for the filter? 

[ronmanfredi]

38 minutes ago, DobbM said:

Hello all. I'm trying to cool off the cabin. I checked the butterfly vents and they are fine. But as I was under the passenger side dash I was looking at the heater box/core area. To the left side is a hole, 2" x 1.25-ish inches and about 4 inches deep. The hole looks intensional, but not factory (super smooth edges, etc.). Was it the place for the filter? 

That is where the heated air comes into the floorboard foot area.

[DobbM]

Oh, I thought that was pre blower. Should there be a flap there? It is the 'Heat'/'Defrost' diverter elsewhere?

And since I don't drive the car in the Michigan winters, would it be safe to cover it?

[mfg]

2 hours ago, DobbM said:

Oh, I thought that was pre blower. Should there be a flap there? It is the 'Heat'/'Defrost' diverter elsewhere?

And since I don't drive the car in the Michigan winters, would it be safe to cover it?

The heat/defrost diverter is inside the heater box itself.

[DobbM]

I covered this hole with some foam (temporary) to see how it affects the heat. According to my passengers, they don't feel the warm air any longer. I also decided to see where else the heat could be entering the cabin from. There's the firewall with the engine and the exhaust system below (in fact, the mufflers are under each of the front seats). So, I added a ceramic and metal blanket over the top of each muffler to start. I may cover some of the exhaust tubing and see if that helps too. 

I can definitely tell a difference by covering the mufflers. And it didn't start a fire! This is the product: https://amzn.to/4v80Ywl

Any words of warning?