Dynamat - Any fuel issues?

[Damo]

Heya gang.

ill be installing dynamat into my car as my audio system build progresses, and want to get rid of as much road noise as possible.

Being that dynamat can get quite heavy in significant enough amounts, I ask if anyone has noticed a drop in fuel efficiency or any other negative factors aside from the cost of the dynamat? :)

[TOLMACH]

to reduce the noise to the noticeable level you would need at least 50-60 kg of dynamat.. which will sure be noticeable for fuel efficiency - expect to lose some mpg

[fnkngrv]

additional weight will always hit you in small cars either performance-wise or mpg-wise. You make trade offs really. For example going boosted with a turbo. You will NEVER maintain the same mpg rate you did before. With this car you can still have great mpg, but it WILL take a hit. If I remove my sub box even, that being 50lbs I gain even just 1 mpg. That is 10 mile miles per tank...ten tanks that is 100 miles...it adds up. You just need to decide what is more important to you.

[talnlnky]

Heya gang.

ill be installing dynamat into my car as my audio system build progresses, and want to get rid of as much road noise as possible.

Being that dynamat can get quite heavy in significant enough amounts, I ask if anyone has noticed a drop in fuel efficiency or any other negative factors aside from the cost of the dynamat? :)

I've got roughly 50lbs of mat in my car and there is a big difference in road noise. I did not see much of a change in mpgs/efficiency. If you think about it... just drive around an 8 yr old in your car and see if that changes your milage... it'd give you similar results.

if you are really serious about about reducing rattles, and have plenty of time, i'd recommend putting multiple gallons of the liquid deadener on the floor boards and firewall as that stuff adds weight but also hardens so it adds a bit of rigidity too which mat doesn't do (mat is just weight).

[derickveliz2]

FYI...
I have more than 200 pounds of extra weight from many CLD Tiles, Mat, and about 100 sq feet of MLV, ...

I still get 43.2 mpg in summer and 40.2 mpg in winter.

D.