I installed dynamat throughout the car then placed some B-Quite mat on most of the interior. I don't have any drone and I have Stingers with LG headers and no cats. It's great!

 

You could just do some C5Z Ti's. Lose a little power, but lighter (almost enough to make up the difference), and zero drone.

I hear corsas don't have the drone either (haven't experienced them first hand).

I don't understand why someone would do some kind of loud catback for 10 hp, and then add a bunch of weight.

The statement about the cabin harmonics makes sense... you might absorb some of the sound, but you still have the same interior shape, which is making the problem....

Which makes me curious... is there a similar drone in a FRC/Z??

 

Well,I can only clear it up for you with my experience

#1 The mods were done in stages,I have had this catback for 4 years and have been quite happy with it until I changed the gear ratio

#2 I do not care for the look of the TI exhaust (Pretty dull and very generic shape)nor the sound..just not enough of it....

So, that leaves me with what,.........change exhaust,skip the lt's, deal with sound deadening,or a bumpin' stereo

I would not be going from 3klbs to 4k,I would only be adding what, 30lbs max?

I don't see that as a big deal at all. Heck why would you ever even drive with a passenger in the car if that's the case?

BTW, that's a good question on the frc ..

 

Right now I'm running LG streets + the supplied x with the Tis and it's quiet when I'm off the gas and loud when I'm on. Not as loud as the outgoing magnaflow system, but definitely nowhere close to quiet.

True. So you're adding 30# of sound deadening material, but then you have to consider the Ti's are somewhere near 20# lighter than a steel rear section. 50# is worth about 6 hp... which is pretty much the difference I imagine you'll see in a bolt on car

 

Ok,you have done your homework,but my math is slightly different
My lg pro's are 20 lbs lighter than the stock manifolds and midsection.
My prt's are only 10 lbs heavier than ti's,and @ 10 lbs lighter than stock

That's 30 lb decrease,therefore I now have made room for the 30 lb's of sound deadening..........it's a wash

Of course your car will be lighter, but mine will be the same as stock

 

drone is low frequency, 1/8" of any kind of foam isn't going to help you in the least. You need at least 3-4" thick foam everywhere. So in other words - screwed.

a lead based sound barrier might work.

 

Put fiberglass insulation (type you put in walls) in plastic garbage bags and place them in the three storage compartments in the rear. It is amazing the road noise that is eliminated! It costs almost nothing and can be removed whenever you need to carry items in the compartments. I doubt it will help exhaust drone but it quiets overall noise noticeably.

 

Wow, you guys resurrected an old post.

Since I'm here, heres my 2 pennies: Before and after frostking mod, I noticed a VERY large reduction in road noise, and a MINIMAL if any change in the drone.

 

This will help muffler noise also. I have a post on this:

http://forums.corvetteforum.com/show...+soundproofing

 

yep; Frost King is best when used on bone stock cars where the owner would like light to moderate interior sound reduction. It's very lightweight and inexpensive.

For powerful aftermarket stereo systems or droning aftermarket exhausts... FK won't cut it by itself... it's not dense enough. You'll hafta just bite the bullet and purchase Dynamat Xtreme, D'Amplifier Pro, and other similar products... pay the extra costs and accept the 100+ added pounds to the car.

And even with these more denser products, you still won't compltely eliminate drone. I mean; you can't Dynamat the windows ...

 

ARH + Corsa Indys = No Drone, and menacing at WOT

 

But I love my prt's!!!

 

You need to do a combination.

1st, use B-Quiet. Same type of stuff as dynamat, but reasonably priced.

Then over top of that do a layer of frost king.

Double Up the frost king behind the seats and on the back wall of the rear.

Get a Lloyds mat for the rear.

Get a coupe partition.

Get the accoustic foam, bag it with one of those air-seal bagging systems instead of trash bags so it looks nice and neat, and fill the rear storage compartments with them.

Good luck.

 

I have asked this before but never received an answer; instead of the insulation in bags has anybody ever tried expansion foam? It seems like it would make a bigger impact, especially since it will expand to fill every crevice and fit very tightly.

 

I could see molding some foam 'plugs' i'm sure no one here is going to spray that stuff in and let it stay though. (put garbage bags in, spay full, shave the top, pull the plugs, you're good to go) I had good luck with the frost king stuff, of course, I don't have my exhaust on yet either. Final story, this car is 4-5 times as loud at any speed than my Grand Prix, and if she thinks i'm going to "talk to her" while we drive, we'll take that car....

 

I have Dynamat Extreme in my car. It made a HUGE difference for cutting down on road noise. It didn't do squat for drone reduction. I had to change exhaust to fix that problem.

 

I cant believe no one has said this yet but, you DO NOT need to add 100lbs worth of dynamat or similiar heavy stuff to get good results. I used a layer of RAAMat BXT and a layer of their ensolite (closed cell foam) and got drastic results. At the most this added 30-35lbs to the car, AT THE MOST. Its very light weight stuff. I have supermaxx LT's and B&B cat back speedway tips, this car is LOUD! The drone is significantly reduced and road noise is all but gone.

I could be wrong on the physics here, but I believe the goal isnt really to absorb all of the dron enoise as much as to stop the vibration of body panels wich acts as an amplifier to that noise. This is what the RAAMat does, it decreases the amount of vibration. The ensolite is there as a sound absorber, but a layer of foam alone will produce minimal results when compared to adding in RAAMat or similiar (its butyl based). THe weight advantage of frost king isnt really worth it when compared with RAAMat.

Do a search over in the audio section, there have been plenty of discussions on it.

 

Ensolite is the cheapest foam solution by far, and one of the best in sound reduction. Its NOT self adhesive though.

 

I have been a proud owner of a stock 2004 Corvette now for 10 months. And I have learned a lot from the postings on this forum. About 9 months ago I placed Frost King duct insulation in the rear compartment of my Vette (sides, bottom, the compartments… basically every possible corner) and I was amazed with the reduction of the echoing exhaust sound. Last night, after reading several other postings suggesting the use of foam padding, I ventured over to Walmart and purchased a package of foam padding (for the use over the bed top). I purchased twin size bed package and filled the hollow compartments found in the rear. I simply folded the padding lengthwise and cut out approximately 16 inches of both ends and placed those in the smaller compartments and used the center of the padding to fill in the larger center compartment. I secured the covers and off I drove to enjoy the now further reduced echoing exhaust sounds. Again, my 2004 is entirely stock but the exhaust sound is nonetheless quieter – a near hum-like sound.

 

I did the FK mod but I also purchased 3 “wedge” packs of Dynomat Extreme (DE). I used one in the rear compartment by cutting chunks large enough dampen each little section. I would test each section by knocking on the panel and if it was dead sounding I would move onto the next section and then place a chunk of DE on it and then re-test again by knocking and it would have a dead thud afterwards. I then covered it all with one or two layers of FK. In the front section I used two packages of DE. Behind the seats required the most DE and two layers of FK. I was very impress with the results and the total cost and weight added was very reasonable. I also did the rear fender wells with FK and filled the center frame/body holes with fiberglass insulation per Mike Mercury’s instructions.