Cab Resonance!!

Jimmy_D · 11-01-2009, 02:49 PM

01 chevy 4.8 with headers no cats and a single in dual out with turndowns.. Horrible cab resonating at normal driving. Sounds good at wot and idle etc.. how to fix the really bad drone in the cab?

94_c/1500 · 11-01-2009, 03:53 PM

If you don't like the drone, maybe you could use Dynamat extreme.

Tweaks · 11-01-2009, 04:23 PM

Everything about your setup is working together to create the resonance, especially the lack of cats. You didn't mention what brand or style of muffler you are using, but that will be the one thing you could change in hopes of reducing or eliminating the drone. The other option would be to get rid of the turndowns and run the exit all the way back or at least behind the rear axle.

Jimmy_D · 11-01-2009, 10:39 PM

flowmaster.. Yeah i've got to do something its the worst out of all my vehicles i've had in the past with the same setup

Underpowered · 11-01-2009, 10:45 PM

flow master.....check
no cats.........check
turndowns.......check

sounds like the perfect recipe for killer drone!

i am nearly drone free with my headers, no cats, and i have a hooker aerochamber muffler. hardly any drone at all compared to my old CB extreme, which had less drone than my flow 40

Outlawz2004 · 11-01-2009, 10:53 PM

extend those turndowns past the rear axle and that will help. Swapping that flowmaster will really help. I have longtubes, no cats and slp loudmouths with no drone, dumped just over the rear axle.

Chris_Harper · 11-01-2009, 11:28 PM

I have Hooker LT, Dynomax race bullets, exits in front of rear right tire, no drone.

GreaseDog · 11-01-2009, 11:39 PM

Quote:

Originally Posted by Underpowered

flow master.....check
no cats.........check
turndowns.......check

sounds like the perfect recipe for killer drone!

i've got 2 of 3, and no drone. put a tailpipe on it.

Jimmy_D · 11-03-2009, 05:37 PM

ill try the tailpipes. its a si/do.. i wonder if i can run a single pipe back and then have the muffler and turndowns?.. easier to run one pipe then two and the turn downs are already on it

Jimmy_D · 11-03-2009, 05:40 PM

straight pipes might have less drone lol... geees its bad

F4MOU$ · 11-03-2009, 05:41 PM

If you don't want drone in your truck, put your cats back on and ditch the blowmasters

93ChevyTBI · 11-03-2009, 06:16 PM

I happen to have the same problem. Can someone point out the cheapest way to fix it....add cats or get new Delta Flow 50 series? Cats are about $50 each and Flowmaster are $97. I'd really hate to put new mufflers on it and still have the drone. Delta flow 50 series is supposed to be quiet but I'd rather get the info from you guys than spend the dough for nothing.

94_c/1500 · 11-03-2009, 06:37 PM

Flowmaster 50s are quiter than 40s.
If you get a good high flow cat, the noise level really won't go down.

Tweaks · 11-03-2009, 08:21 PM

Get anything other than flowmaster and you're probably heading in the right direction. How loud or quiet isn't as important as the muffler's ability to cancel out the really low frequencies that create the drone.

96gmctruck · 11-04-2009, 08:48 AM

I don't have a problem with noise with my flowmaster super 44s. put some tailpipes on it and you'll be fine.

oneloudz71 · 11-04-2009, 09:07 AM

The further back you can move the muffler and the turn downs the less drone you will have.

Here is an example. I have a crew cab with a cat back magnaflow system that exits before the rear tire. I have quite a bit of cab drone. I have a customer with the same truck that has a magnaflow cat back system with the same muffler and his exits out the rear, no drone. The reason I have so much drone is my muffler sits right under the rear of the cab, his sit under the front of the box out from under the cab. Also mine exits 3+ feet closer to the cab than his. Like I said, same exact muffler, same exact trucks, different muffler location and exit, night and day difference in cab drone.