shelbymustangdan

Hello everyone,

As I am about to Dynamat the firewall, toe board, and floor of my 67 Fastback, I was wondering if there is any benefit to putting it on the underside of the cowl?

I don't think there is.....but thought I would get some opinions.

jimkaray

Depends on your goal. If sound blocking is the primary need then Dynamat isn't the ideal solution, its mostly about killing resonance. MLV is extremely effective at blocking out sound. You can research the available products and their applications here: sounddeadenershowdown.com

shelbymustangdan

Blocking heat is primary, sound is secondary. (overall goal) I can't see too much heat coming down from the upper cowl metal under the dash.

After putting the Dynamat on the firewall, I have new reproduction Firewall Insulation (mass backed) to lay over top to help with heat.

jimkaray

Sounds like your blocking the engine bay heat from radiating in pretty well. Can't see much heat there worry about. Although, I expect there will still be some hot air pushing in through the cowl, etc and warming the incoming air. Anything you can do to lower/vent under hood temp would help. Since your focusing on heat I'll assume you're looking at heat coating at least the exhaust headers.

Coupe

I put some there, just because the wind running through the cowl could have added a slight rumble or "Tin can" sound to the dash area....I happened to be there anyway so I stuck some one, cant hurt I guess.

shelbymustangdan

I have some JBA ceramic coated headers in place with a 2.5" dual exhaust. I think I'm on the right path to help reduce heat. I'm also trying to plug up as many gaps/openings as possible while I'm under there. Example: That rubber "donut" around the steering shaft casing, on the inside, wasn't fitting well at all. I don't know if they ever do, but I need to focus some time there, as that is a major "wind tunnel" right up my shorts! ;o) The 408W I have in there seems like open furnace on warm days. ;o)