hisvett

After insulating my C6 GS with a foil over bubble wrap kit purchased from a CF vendor a few years ago and finding no gains in sound or heat improvement, I did a lot more research on products before trying it again with my C7. The best “Bang for the Buck” with realistic results I felt was Dynamat Extreme; I found a 32 sq. ft. kit of .080 thick sheets on line with free shipping (delivered the next day)…..EZ to find with a Google Search.



I took my time with the job mainly because I don’t fold up in small places like I used to 30 or 40 years ago. All in all, it took about 10 hours of bending, twisting, standing on my head to finish the work. The Dynamat material is very easy to work with; just cut with a razor knife and press (FIRMLY) into place. My material waste was way less than 1% because I would fit all the small scraps into the nooks and crannies as I went. NOTE; the C7 floor is nothing like the earlier flat cargo decks. The new cars have many humps, ridges, peaks and valleys to work the material into. I found a roller to be little help; instead, I used the handle end of my razor knife to work the material into all of the corners (just retract the blade first). You MUST really work the material into the deck surface, don’t just lay it on the surface and rub a little with your fingers. The Dynamat must become one with the car….absolutely NO AIR bubbles between the deck and mat!

To start with, here’s a before and after sound check video;


To start the install, remove the 4 tie down rings using a #40 Torque Driver after popping the plastic caps off that covering the 4 heads of the Torque anchor bolts;



Next, remove all the plastic trim pieces…..the small insert piece around the Targa Top mount needs to pop out first before removing the side trim panels.



Removing the rear trim panel does make it a little easier when removing the corner carpet around the storage area. The corner carpet will need to be removed to gain access to a 10 mm nut that holds the framework for the storage lid.



Be careful when removing the cargo floor carpet from around the storage compartment; there are 3 gator clips that anchor the carpet around the lid. Remove the carpet, then the framework, then the storage liner. Now you are ready to vacuum and wipe down the floor surface with a thinner rag.




Just to get an idea of how much area 9 sheets of material would cover, I laid them out; 3 to cover the cargo area and two for the bulkhead….leaving 4 sheets to ether do the drivers area or double up on the critical sound areas….I went for quality rather than quantity.



DO NOT strip the full backing off the sticky side of the Dynamat, it is way too difficult to work with. Instead, cut through just the paper backing making several strips so you can work with one section at a time.



I put one layer of Dynamat down on the cargo floor and bulkhead, plus a layer on most of the wheel well area. I then applied a second layer to the bulkhead and center of the cargo area. NOTE; the wiring harness/limit switch looms are just double stick taped to the bulkhead and can be removed with a little (perhaps a lot) of pull and a few choice words.



Here’s a shot of the underside of the cargo and bulkhead carpets;



NOTE the 3 Gator clips around the storage compartment;




Now that I have installed all 9 sheets of Dynamat, it’s time to start replace the interior. Replace the storage area liner and framework first, remember to anchor the framework to the sidewall. Now replace the bulkhead carpet first then the cargo area carpet.





Replace all the plastic trim panels and tie down rings. Now test drive



My results; some time ago, I used a sound meter app on my phone to check the interior noise at 70 MPH on a section of I35W not far from my house. I use my Chrysler 300S as my baseline subject just in case my phone calibration, or phone app, or getting a new phone should change. I have established that the 300 was 10db quieter than my 4LT C6 GS and my 3LT C7 Z51 was almost 5db less than the 300 under the same road and speed conditions tested at the same period of time. I know this is not a real calibrated number but who cares, I’m just looking for the Delta between “before and after”.

So now with the job finished, my sound meter is reading slightly lower (just less than 1db) in the 300 over the C7 under the same conditions; very smooth tarmac surface at 70 MPH. MY EAR confirms this while on a nice smooth surface; where my ear disagrees with the meter is on a concrete surface with expansion joints. The suspension and smaller sidewall tires on the Vette seems to amplify the “Thump-Thunp” of the joints over the heavier softer riding 300 (NOTE, both cars are running Non-Runflats). The sound meter does react to the joins but only slightly, not nearly as much as my ear. I’m sure my ear is more sensitive over a wider band width than my phone but one works with what one has. Bottom line; my ear feels a difference and the “Right Seat Boss” thinks it is quieter too….and that’s all that matters!

FYI; here's all my photos for review; http://s147.photobucket.com/user/his...20Installation

speedlink

Nice writeup. Well done. Thanks for posting.

C8Jake

RATTLETRAP XTREME

robert miller

The dynamat is some really good stuff but the weight of it is a ton. But I did put it in my 57 chev H/T & my c2 conv. Makes a world of diff's. Due to weight I put of other stuff in the c7.

halt00

What is up with the wrinkle in the leather on your console lid?

///ADMAN

Nice having the extra 2.8HP with all of that extra weight now