hood insulation

[clgodwin79]

Those things kind of seem like a mute point to me. No way should your engine produce enough heat to hurt the paint on top of your hood. And no way should the sun coming down heat up your engine compartment to make that big of a difference vs the running temp of an engine being in the 200’s anyway.

So I’m not saying that you’re wrong to run the insulation, factory, replacement, or something along the lines that Kenny did. But I’m also saying that I can’t foresee any catastrophic things that can happen from NOT running one.

There’s a LOT more open space under these trucks to the ground below the engine compartment. And also a lot above the top of the engine before you get to the hood. And there are a lot of cars with a super packed and cramped compartment that don’t breath nearly as well and without a free square in, and where the hood only clears the top of the engine by an inch or so, that don’t have any insulation and I’ve never seen it affect the paint or engine temp negatively one way or the other.

But to each their own. I’m just saying that if it’s crappy, rip it out. But don’t worry about anything bad happening if you run without one either. Just my opinion though.

 

[Dropped88]

Roof gets hotter on a dark car in the summer then the engine could ever get the hood.

I had a cherokee at one time thatwas over headed to the point it discolored the white paint on the hood but it never faded, peeled, dulled.

 

[stutaeng]

If I'm repainting a hood I'll usually remove since it's most likely in bad shape and won't replace it.

I asked my buddy that does collision repair and he said the insulation is there in case you have a fire in the hood. He claims the insulation falls off and can extinguish the fire. I honestly don't know if that's likely, but that's what he said. I also thought it was to protect the paint from engine heat.

 

[kennythewelder]

After I buffed out the aluminum under my hood, I posted pics of my work. I got a lot of comps, but members were saying, now you need to do something with the under side of your hood. So I looked at replacing the insulation. I though, no, I want something better than OE. I found this, and though, hell no, that's to expensive, but I liked the idea of the bowtie. So, I decided to build one out of aluminum. I made the smaller one first, but it wasn't big enough. So I then made the bigger one. After I made them, I thought about back lighting them with LEDs, and hooding that up to the hood light switch. When I was ready to install them, I tried to pull off my insulation and clean it. Well it fell apart. That's when I though about the bed liner. I even had a can in the house. That's how it all came together.

 

[SAATR]

It's likely that the insulator serves to prevent or correct NVH (Noise, Vibration, Harshness) issues as much as anything. A large piece of sheet metal like our hoods with minimal contact and securement points can turn into an amplifier for engine noise, and resonate at certain frequencies (engine RPM, road speed), so damping engine noise and hood vibration is probably a primary function.

 

[smdk2500]

I agree with the above post. My 6.5 truck has it on the firewall as well. When I was pulling the bolts on the fire wall to remove my heater box the insulation crumbled as I touched it to get it out of the way of the bolts. Im missing half the insulation now. I can now here my exhuast leak inside the cab as well as other engine noises that I couldn't hear before.

 

[Caman96]

it.

I asked my buddy that does collision repair and he said the insulation is there in case you have a fire in the hood.

I’ve heard this too, but also could serve as a noise dampener as SAATR pointed out.