don't know how that thing in red called

Is it ok to run in winter without that "thing"?

 

I put in no. Not that it cant be done but because it would not do anything for you.

 

maybe engine bay will be a bit colder and hood will be lighter.

 

Some people do remove the hood lining to reduce weight. I don't know how much it weighs, but have you seen the stuff that's inside it? I accidentally poke a hole in it and some yellow looking material came out. Probably for sound deadening purposes.

 

well, you do take a chance on having a louder engine and perhaps baking the paint a little faster.. but that is about it. My fiat does not have the sound deadening material, it fell down years ago (30 year old glue) and I had not had a problem without it. It is interesting when it rained though, the water on the hood over the engine would steam.

 

That protects your paint from engine heat.

There are aftermarket ones available that are lighter, or deaden more sound.

 

I took it out the other day. It weighed a good bit... maybe 6-7 pounds? I dunno... I didn't notice too much of a noise increase.

 

will it only affect the paint under the hood or will it affect the exterior also?

 

Both. eventually the heat will bubble the paint off of the hood. Where as a CF hood is not painted you dont have to worry about this.

 

Not true. My old CF hood got baked/bubbled because it didn't have a heat-shield. I had to re-isntall my old one to stop it. Fiberglass/CF epoxy does NOT like high tempatures.

You can remove it if you want to, but it does server 2 purposes. #1. Keep engine heat from baking your hood/hood paint. #2. Dampen engine noise.

While it's not "great" at either job, it's a lot better than nothing. The "5 or 6" lbs you save are not going to significantly affect your fuel economy or acceleration times.