Noise Control

[robert j. yates]

Everyone knows that a soft top Wrangler can be a noisy proposition and over long distances, that it can become quite annoying. Since my ears are 50 years old and a little on the tired side, I needed a solution and since I had a few days off over the holidays, I was able to catch up on a project that I had sitting around in my garage.

I have been a fan of ThermoTec/Cool-it products for sometime ever since I found a set of spark plug booties made by them for use on my Suburban after I installed a set of headers. I've also used their header wrap so when it came time to deal with heat and noise control inside of my TJ...I hit up their website and I found this....

http://www.thermotec.com/product_detail.php?prd_id=25

I liked this product due to the fact that it could be used without an adhesive which is what I wanted. If it gets wet, I can simply yank it out and let it dry in the sun and then slide it back in.

Quite simply, with a good set of shop scissors and a small cutoff wheel on my Dremel tool, I was able to install this mat under my driver and passenger seats front and rear, as well as cover the entire floor of the rear tub in a couple hours time. The Dremel tool was needed to accomodate the numerous small cuts required by the frontmans on the rear tub floor as the cuts were to small for my shop scissors. For the footwells, I simply copied the shape of my factory floormats and so far, it has seemed to work well and does not cause any interference with either the carpet or floormats. For the rear floor, I simply pulled the carpet and outlined the locations of the frontmans with a Sharpie and then used the Dremel to open up the cutouts.

I have only spent one small trip to get to a local ski area in the Jeep since I installed the mat but there is a fair difference which was noted by both my wife and my brother. Now if I could figure out a way to keep the top from flapping around, I would have it made. Hope this little install tidbit helps others wanting to quiet down their Wranglers. Cheers

 

[RobinP]

Robert, that stuff looks great!

Will it hold water if it gets wet? How easy would it be to dry?

 

[PhulesAU]

I'm confused, How did the sound barrier on the floor effect the soft top? I must have put my soft top on wrong, It doesn't flap or make anymore noise than any other soft top vehicle I've owned. have you tried padding the spreader bars, to maintain tension in the top? is the frame / top properly installed?

 

[Scott Brady]

Padding the center bar really helps. So did upgrading to a "sailcloth" top.

 

[robert j. yates]

Sorry for not responding earlier but I have been up in the Sierras for the past week

Anyways.....after 900 miles with the Jeep in some pretty extreme weather, I can say that for the $70 I spent on the aluminum backed insulation I posted above, that it seems to be a reasonable investment. It didn't solve all of my noise problems but it does certainly help.

Does water seem to affect it? Other than soaking the hell out of my carpet, it does not appear so. It will sop up water just like any other insulation does but it seems to dry out in the same manner as my carpet. Also since I cut the pieces to fit under the floor mats and did not use an adhesive, they are easy to yank out and expose to the air which I did last night after I got home. I also think that the added insulation was a bonus for heat retention in the cabin. I have no scientifc proof but my wife and I were always warm and toasty.

As for the soft top, I apologise for the confusion but that was a sarcastic swipe at myself. My Jeep was on its side out at truckhaven many years ago and I doubt that my cage is straight which explains the weird tension on my soft-top. Ever since that occurance, it has flapped and outside of adding a sail batton, I doubt I will get it to stop.

 

[dynamike]

Sounds interesting......
its kinda funny after driving soft top Jeeps for years, you become very use to all the Jeep noises. So much in fact when I ride in somebodys luxury car, it almost sounds so quite it's Spooky......and Way to smooth also.
The newer LJ has a fair amount of insulation under the carpet, but I have always wanted to make a liner for the soft top, helping with heat, and possibly noise.
I ran across SavageSun's website and he posted a soft top liner. I have been contemplating this, but I need to use the stock sports bar vs. his aftermarket roll cage.
Anyway, Robert, I'm sure you will find as summer comes your idea, will help with keeping the heat down also.
SavageSun's liner http://www.savagesun4x4.com/camo_head_liner_for_tj.html

 

[PhulesAU]

Ahhh. The body flex explains a lot. Just curious, did the header wrap make much difference? If it did, can you wrap the Cat. Conv.? I'm thinking a reduction in the chance of brush fire hazard.

 

[robert j. yates]

I would not use header wrap on the catalytic convertor due to the extreme amount of heat that it generates but I did use it on my Spintech Sportsman muffler. Due to my trilinked rear suspension, the muffler sits very close to the upper control arm joints and the floor....the wrap eliminated the issue I had with toasting the poly joints and it also seems to keep the floor of the tub cooler.

 

[madizell]

Header wrap as a general application is not recommendable outside of drag racing where service life is extremely short to begin with. Wrapping headers, in limited applications, has some value particularly if you have stuffed a 500cid Caddy motor into the bay of a small car, but as a rule, trapping heat in the headers only shortens the life of the headers, sometimes dramatically.

I wrapped ceramic headers on my Jeep back when it had the 2.5L AMC 4 cylinder, and the wrap not only immediately discolored the ceramic by trapping mud and junk against the ceramic coating and then raising the temperature of the material to near-molten state, but caused the ceramic to flake within a few months because it pushed the ceramic-metal interface beyond the elastic limits of the materials. Nor did it actually do anything for the performance of the vehicle. I would never wrap a cast iron manifold unless you really want to see how far cast iron can bend.

At best, all that header wrap will do to headers is push the heat downstream. Headers are generally made to withstand 1,200 to 1,600 flame temperatures found in the first few inches of the exhausts system, but the balance of the system is not designed to withstand these temperatures. Nor are the headers intended to withstand the flame temperature of exhaust while wrapped, even if not coated with ceramic. The wrapping will raise the temperature of the metal, often to the point of a strong glow, and the metal will erode rapidly. Headers withstand high heat because they are able to shed that heat through the tubing walls. They get hot because they are supposed to do so. That heat you feel is cast off heat. That's what keeps the system at less than a molten state.

If you need to protect objects from the heat of the exhaust, wrap the object to be protected, not the exhaust system.

 

[DaveInDenver]

Header wrap as a general application is not recommendable outside of drag racing where service life is extremely short to begin with.

This was what I'd always understood. Both mild steel and stainless headers that are wrapped oxidize at much faster rate. Coated headers don't have the same problem, however the coating tends to crack. In any case, most header manufacturers will not warranty them if they are wrapped. Most race teams wrap their headers because there is a performance gain, but they also replace the headers a lot more often. A ceramic coat alone reduces the temperature around the header by a ton.

 

[robert j. yates]

Header wrap as a general application is not recommendable outside of drag racing where service life is extremely short to begin with. Wrapping headers, in limited applications, has some value particularly if you have stuffed a 500cid Caddy motor into the bay of a small car, but as a rule, trapping heat in the headers only shortens the life of the headers, sometimes dramatically.

I wrapped ceramic headers on my Jeep back when it had the 2.5L AMC 4 cylinder, and the wrap not only immediately discolored the ceramic by trapping mud and junk against the ceramic coating and then raising the temperature of the material to near-molten state, but caused the ceramic to flake within a few months because it pushed the ceramic-metal interface beyond the elastic limits of the materials. Nor did it actually do anything for the performance of the vehicle. I would never wrap a cast iron manifold unless you really want to see how far cast iron can bend.

At best, all that header wrap will do to headers is push the heat downstream. Headers are generally made to withstand 1,200 to 1,600 flame temperatures found in the first few inches of the exhausts system, but the balance of the system is not designed to withstand these temperatures. Nor are the headers intended to withstand the flame temperature of exhaust while wrapped, even if not coated with ceramic. The wrapping will raise the temperature of the metal, often to the point of a strong glow, and the metal will erode rapidly. Headers withstand high heat because they are able to shed that heat through the tubing walls. They get hot because they are supposed to do so. That heat you feel is cast off heat. That's what keeps the system at less than a molten state.

If you need to protect objects from the heat of the exhaust, wrap the object to be protected, not the exhaust system.

I'm not going to disagree with anything you said but why would you wrap a ceramic coated header? That to me as adding redundancy that you simply don't need. The ceramic coating is meant to accomplish the same thing as header wrap. FWIW....I am planning on having my entire exhaust from the downpipe to the tail pipe including the muffler, ceramic coated for complete heat control . I probably wouldn't need to do this but for a highly modifed engine and rerouted exhaust which gives me some heat control issues.