Can the 'box' behind the seats be filled with foam? If the box contains a cross member support between post "A" and post "B" and thats all, then what would it hurt to 'pump/blow' expanding foam ( weather proofing foam -Home Depot-) in it for sound supression. I figure it acts like a big drum, keeping beat with the Michelins...
Xfire 2004 Coupe

 

You could fill it with foam.... but then you wouldnt have any place to put your gas... that is where the gas tank sits.....

 

Welcome to the forum Fugley...theres tons of info about the cars to help ya along with ideas and mods etc. Practicaly everything thats ever been thought of has been talked about at some point. never hurts to ask though

 

Still, put the gas in THE TANK. Now, if the space that is left in the transverse support box and the tank is foamed it seemed to me it would help sound supression. I don't know...I figured someone may have tried it before me. I did a 1975 Dodge Caravan. But that was for "oil canning" side panels.
If no one has done it, I guess I'll be the first.

 

I haven't been inside the drivers side of the divider, but the trunk side dosent have much covering it and the tank....just the thin black material you look at when you open the tailgate.... It comes out very easily...

I would take a good look at what is under the people side and what you might be covering if you foamed it up.... some removable foam/deadener wouldnt hurt anything though....

There have been a couple of guys that have done extensive work on deadening the outside noise on their car..... the rear wheel wells, styrofoam area under the rear mat, between the license plate and cargo area, door panels and I believe the floor/firewall too... using dynamat or similar material... maybe even some in the hatch itself...

 

Heres a quick shot from my roll bar mod, I didnt pull the carpet back all the way though. The subs are right below in the pic and may be a concern when foam gets in back there. I honestly dont remember much about the black vinal sheet (shown in pic) didnt pull it back to get in there but it could be hollow

 

I'm not sure I'm doing this right. (repyling here).. So this is a test.
Thanks for the response, at least I don't feel alone in trying to suppress the road noise. Some one else has done it! Maybe I'll find out how to do the wheel well too. (foam?) As you guys know...anything should help. I was surprised to see the lack of info pertaining to XFIRE noise reduction on this site.
Who has ever seen a Quite XFIRE!
Any more sugestions?

 

fugley, I meant the wheel well from INSIDE the car....

inside the cargo area there is a LOT of hollow space behind the cargo area liner.... over and behind the wheels, under the mat and some under the hatch and the area below it....

edit: I did a search and here is a link that shows the cargo area without the liner. You can see the potential for deadening here.

https://www.crossfireforum.org/forum...reduction.html

edit2: here is the link to the one I was thinking of...

https://www.crossfireforum.org/forum...oad-noise.html

 

I've had good success using R-Blox, an adhesive backed Dynamat like material. A roll of Dynamat was over $300, the Rblox was $89. for a similar sized roll. The stuff works wonders, just cut to size, you can cut it with scissors to a sheet or strips or patches or any shape, peel the backing and stick it on. Best to be done on a warm/hot day as it is eaier to work with. Much easier to control and apply than foam. It is heavy though, it took me about 6lbs per door to do the last car that recieved the treatment. A large roll weighs in at 40lbs. Search Ebay for Dynamat and R-blox and you'll see the price difference.

Alan

 

this link has pic where Howard laid Dynamat in the trunk of his Roadster. https://www.crossfireforum.org/forum...ling-down.html

Another one: https://www.crossfireforum.org/forum...oad-noise.html

 

Using 1/8" particleboard, I cut a sheet out the same size (slightly undersize actually) as the fabric floor cover in the rear cargo area. Then I bought 1" thick urethane foam sound absorbing material (the same stuff on my hoodliner) with one sticky side and attached 1 layer to the top side of the particleboard and 1 layer to the bottom side. Total thickness = 2.125". Place underneath the fabric floor cover and it cuts out a lot of the road noise inside the car, especially at speed.

This is much better than Dynamat, cheaper, and reversible.

I'm not sure what you can do with the box between the cargo area and the seats. Access is needed in there, so a permanent foam fill would be ill-advised.

 

Hey thats a great idea and sounds easy enough to pull oiff,,THANKS!

 

Where did you find 1/8" particle board and how did you handle it so it stayed in one piece?
JBA

 

I find turning up the radio or cracking the windows open effectively deadens any vehicle noise.