Gasdoc's ERA build - #813

[DanEC]

[quote=Gasdoc;1393795]
I saw where some folks are installing Cool It or Dynamat under their carpet. Is this worth it for heat or noise?
QUOTE]

It all can be a little maddening. People love to help you spend your money. I think we live vicariously through it since we don't get to build a car every year.

With side exhaust you don't really need insulation underfloor. You may want to add some to the top of the foot box since it isn't insulated on the engine side. Possibly the outboard side of the fool box also for the same reason. You will need some insulation for the transmission tunnel. I would use something like this for lightness and insulation value.

[ame="http://www.amazon.com/Thermo-Tec-14100-24-Cool-Mat/dp/B00029KCW0?ie=UTF8&*Version*=1&*entries*=0"]Amazon.com: Thermo-Tec 14100 24" X 48" Cool-It Mat: Automotive@@AMEPARAM@@http://ecx.images-amazon.com/images/I/51jLlxmoutL.@@AMEPARAM@@51jLlxmoutL[/ame]

Only issue is it isn't self-adhesive so you have to use contact cement.

Another option is to simply go to Lowes or Home Depot and buy a roll of Frost King duct wrap. This is what ERA uses to insulate the engine side of the foot boxes and it is self adhesive and inexpensive. It does weight a little more but not as heavy as something like Dynamat.

As Bernica pointed out, it is an open car with a loud engine and exhaust so how much sound dampening material do you really want to weigh it down with and for how much good. Because my car has undercar exhaust and is a street car I went a little overboard on mine. I will say it's tight and rattle free. Sound deadner does not need to be applied over the entire car to get benefit from it. You may want to apply a few square feet on the bigger aluminum panels just to dampen some vibration/resonance - say a piece under the seats on the floor board. Also between the trunk floor panel and the gas tank is a good idea because there isn't much separation between them. The panel behind the seats is the other big one that a couple squares could be put on the trunk side if you decide to carpet the trunk. But, I wouldn't go overboard with it.

Good luck.