Exhaust Drone!!

[747mopar]

My last car did it pretty bad when coming down in rpm (dual 2.5 H pipe and flowmasters) but somehow it went away by itself. I just got done building a custom 3" X pipe with homemade (flowmaster style) mufflers and it sound like it may do it as well but I kinda like a noisy car.

 

[dodge413]

The Dynamat In The Rear, And The Trunk/Back Seat Baffle Only Cut Down On The Drone Slightly...
What Do You Guys think About Me adding Short Glasspacks In Front Of The flowmasters? That's Gotta Help With The Drone, Right?

 

[themechanic]

See the Dynomax demo link for the answer

Posted via Topify using Android

 

[dodge413]

See the Dynomax demo link for the answer

Posted via Topify using Android

Thanks For Sharing That Link. What A Great Marketing Tool.

My Question Is Should I Put The Glass Packs Upstream Or Down Stream Of The Flowmasters?

 

[Cornpatch MO]

Thanks For Sharing That Link. What A Great Marketing Tool.

My Question Is Should I Put The Glass Packs Upstream Or Down Stream Of The Flowmasters?

Wouldn't resonators mounted near the back be better to cut down the drone?........................MO

 

[bigblock]

I used to run a cherry bomb as a resonator on either side of the gas tank. Works great but I figured out the problem. I didn't need dual exhaust. I should have had a single all those years. In other words my engines didnt keep the pipes and muffs busy. Therefore had the drone. Anyway the Flowmasters WILL get a lot quieter when they smut up.

 

[themechanic]

Thanks For Sharing That Link. What A Great Marketing Tool.

My Question Is Should I Put The Glass Packs Upstream Or Down Stream Of The Flowmasters?

That's a question for the manufacturer. I think it depends where they will fit.

I may sell my 3" Super Turbos after I listen to the Ultra Flows I have on the car now. I drove about 10 miles and thought the Super Turbos were a little too quiet. But they are suppose to sound better after 1000 miles or so.

 

[fmontez1]

That's a question for the manufacturer. I think it depends where they will fit.

I may sell my 3" Super Turbos after I listen to the Ultra Flows I have on the car now. I drove about 10 miles and thought the Super Turbos were a little too quiet. But they are suppose to sound better after 1000 miles or so.

I hope so, I bought a TTI Exhaust with the Super Turbos in there, and it made me miss my flowmasters. Flowmasters just sounded meaner. I guess maybe the drone doesn't bother me too much because I don't do too much freeway driving.

 

[Budnicks]

Getting Back To The Original Point....

I Took Out The Back Seat. I Notice That The Floors Under The Back Seats Were Very "tin'y", Which Are Right Over The Flowmasters. I Loaded Up Those Floors With Dynamat. Also, I Made A Styrofoam And Fiberglass Insulation Sandwich Between The Rear Seat And The Trunk Because There Was Nothing Behind The Back seat before. I Was Going To Try It Out Last Night But The Weather Didnt Cooperate. I Will Let You Guys Know If These Things Helped.... I Sure Hope So.

The trunk acts like a big base drum, maybe you could put a thin fiberboard partition panel, behind the back seat upper section, like the ones used in the Decore package cars in the 68-70, then sound deadening or insulation like a Jute pad, on top of that & the package tray also {if you really want to stop any noise from coming thru the trunk area}, then some sort of sound deadening {like Dynamat or who ever} }or add insulation under the carpet, under the back seat {I prefer Jute under the seat & partition} & a trunk mat to help lesson all the empty broad spans/spaces of sheet metal, from sending a resonance thru-out the whole car... no matter who's exhaust you choose to run, it helps...

 

[Sonny Black]

Sonny can't hear a dam thing!.......even blast my speakers when driving with the windows up or DOWN.:icon_shaking:

 

[dodge413]

The trunk acts like a big base drum, maybe you could put a thin fiberboard partition panel, behind the back seat upper section, like the ones used in the Decore package cars in the 68-70, then sound deadening or insulation like a Jute pad, on top of that & the package tray also {if you really want to stop any noise from coming thru the trunk area}, then some sort of sound deadening {like Dynamat or who ever} }or add insulation under the carpet, under the back seat {I prefer Jute under the seat & partition} & a trunk mat to help lesson all the empty broad spans/spaces of sheet metal, from sending a resonance thru-out the whole car... no matter who's exhaust you choose to run, it helps...

I picked up some short glass packs, and put them next to the gas tank in the tailpipe sections. The drone is gone! and when you rev it up it still sounds great. Thanks To All!

 

[bigmanjbmopar]

I saw these on fleabay up to 3" wonder if these would work? same type of thing as resonators?

http://www.ebay.com/itm/NEW-PERFORM...|Model:Roadrunner&hash=item232f5adeff&vxp=mtr

 

[rev.ronnie]

I have the TTI system with Hooker Comp headers and Dynomax Super Turbo mufflers. The car also has dynamat. It it incredibly quiet inside. Heat is a non-issue either.

It's so quiet at idle that you can hear the pistons click when it's cold. ( Wisecos @ .004") it has a great sound when you jump on it though.

I'm going to put the same system on my 1970 GS 455.

 

[Cranky]

Actually Mopars have exhaust drone, worse than Ford or GM. It worse when the pipes are not ran out the back. Over the last 30 years I've ran everything from open headers to Turbos, Cherry Bombs, Thrust, Flowmasters, Magnaflows, ect. All have drone on Mopars. Have not tried Dynomax. Have Magnaflows on my 72 and they drone real bad around 45 mph.

Firing order is the same on Mopar and Chevy V8 so why would they sound any different? Body construction and insulation?

 

[bigmanjbmopar]

Walker makes a glasspack resonator that you can pick p at autozone for around $30 each. Going to give those a try in a few weeks. 19" long will fit right next to the tank very nicely.

 

[dodge413]

Walker makes a glasspack resonator that you can pick p at autozone for around $30 each. Going to give those a try in a few weeks. 19" long will fit right next to the tank very nicely.

UPDATE: I Bought A Pair Of Cheap Summit Glasspacks. They Are ReAlly Short, Like 12 Inches. ONLY Problem Was The Pipe In The Middle Was Full Of Louvers. I've Read That This Cuts Down On Flow Drasticly. So I drilled 30 Or So 1/4 Inch Holes In My Tail Pipe, And Cut The Outer Shell Off The Glass Packs, I Slid The Fiberglass And Outer shell Over The Tail Pipes. This Has Completly taken Out All Of The Drone! It Sounds Great Now!

 

[cbunt1]

UPDATE: I Bought A Pair Of Cheap Summit Glasspacks. They Are ReAlly Short, Like 12 Inches. ONLY Problem Was The Pipe In The Middle Was Full Of Louvers. I've Read That This Cuts Down On Flow Drasticly. So I drilled 30 Or So 1/4 Inch Holes In My Tail Pipe, And Cut The Outer Shell Off The Glass Packs, I Slid The Fiberglass And Outer shell Over The Tail Pipes. This Has Completly taken Out All Of The Drone! It Sounds Great Now!

Glad that solved it!

I had a car years ago with the 50-series Flowmasters ('97 T-bird), and with the drone of the flowmasters, I swore I'd never have another set of them. It's not just the exhaust noise--that I can live with, (I'm a glasspack guy by nature) there's something about the flowmasters that creates a resonance I couldn't get past, like you mentioned.

A new exhaust system is on the list for my car...I've been thinking of just doing custom-bent pipes and a pair of 24" glasspacks and call it done, but your solution sounds like an option too...I do like the TONE of the flowmasters from outside the car!

 

[bigmanjbmopar]

Just bought some Jones blank glass packs 3" in/out and 18" long based on a conversation with my local muffler shop. He said he has never seen or installed them in the rear and on new cars they are all in the front. When I told him about the hemi cars having reso's in the rear he just paused and said yep ur right bring them to me lets get em on. in a couple of weeks hope to report back good news. total cost will be $160 installed. He wanted the blank version for an easier install, guess the ones with ends already on the make it harder?

 

[soundhd]

hmmmmmmmmmmmmmmmmm..............

 

[kb67mopar]

The resonators should always be after the muffler, the muffler will remove certain tones and the resonators take out the rest afterward.

I had a terrible drone in my Ram with a magnaflow and ended up adding a summit glass pack just in front of the tip to get rid of it. (same thing Ma mopar did to the factory original exhaust if you look).

For the Coronet I am running 2.5" IMCO chambered mufflers and I think they are going to be ok. They resonate pretty bad in the car right now but I have turn downs on it for the time being and there is no carpet or anything behind the back seat. they also only seem to resonate toward idle.