rayainsw

Car: 2007 Coupe A6 – no other modifications.
System = Quad Tip Model #: 17427

OK – first, these are really, really loud.
Not only compared to the OEM system, but also compared to several aftermarket systems I have had on other cars.

They are loud outside the car – to the point that I am actually wondering if they are street legal. Seriously.

They are very loud inside the car – at almost every combination of speed, RPM & throttle position. And not loud in what I’d consider a “Good Way”.

I was looking for just a bit more of the deep heterodyne beat of a V8 exhaust. But not obnoxious to those inside or outside the car. To add to my enjoyment of driving this exceptional car. And some here appear to share that desire. I have nothing against those who are happy with what I see as a very ‘stealthy’ OEM system – but I wanted a little more audio involvement.

What this system provides ( IMHO ) is a really loud system, but it is almost as if the V8 sound that I was actually looking for is there, but almost completely overshadowed \ overlaid by another set of very annoying, harsh, flat tones - that almost completely mask what I wanted to hear. I really do want more \ better \ deeper exhaust sound \ tone – without waking my neighbors – or giving me a headache when I drive for a while at my typical cruising speeds. ( 70 – 80, mostly. )

For me, as installed, these are no fun at all – under any driving conditions. Just noise – and way too much of tonal aspects I do not want to hear.

The drone is not only apparent, it is amazingly pronounced.

Yes, I read various posts here, before ordering the system. There have been a couple of owners that could not deal with the drone, but at least one had headers on their car – and several had said that the system was viable.

As initially installed, it is absolutely not viable, for me. No way, no how.

The drone is simply overpowering at any engine speed & load, but most intense between approx. 1,100 RPM and 2,500 RPM. I cannot drive around this – and even when accelerating ( where I’d hoped for the ‘payoff’ in sound ) the tones I was looking for, while they do exist, are virtually drowned out by the drone. Just a hard, flat tone that hardly varies in frequency with RPM. It becomes much louder at larger throttle openings – but does not rise ( much ) in frequency as RPM rise on acceleration. Weird. And: Not fun. For me.

So – I will have to do something here – either I will need to find \ figure out a way to modify this system’s sound or replace the OEM system.

After reading a couple of Larry B.’s posts concerning his modification to address the drone in his twin tip Flowmaster system, I did stop on the way home & purchase an exhaust reducer. Studying what I’d have to do to duplicate what he did, with the 4 tips into 2 muffler outlets, I was not certain I could accomplish the same effect.

As a short term attempt to somewhat diminish the drone, I then stopped at Lowe’s and purchased a sheet of perforated metal. I cut approx. 4” x 10” sections, and curled them into 2+ layer cylinders – and tapped them into each of the 4 tips.

My immediate concern was how loud the system would sound as I left my neighborhood before 6AM, as I typically do. This C6 is my DD and only vehicle – so I did not have the luxury of just parking it until the weekend to try to address the noise level.

I truly have no desire to be assaulted by neighbors with pitchforks because I woke them out of a sound sleep, just by driving out of the subdivision early in the morning. This is absolutely not a long term or elegant ( aesthetic ) solution, but:

This did reduce the volume in the car somewhat, and I presume outside as well – and brought the drone at 60 – 80 MPH down a notch or 2. It is now very, very annoying for the 15 or 20 minutes I am typically on the highway during my morning commute – but I’m sure it would still drive me nuts on a significantly longer run. It seems that the worst of the ‘steady-state’ drone is now concentrated between 65 and 77 MPH.

I may revisit the possibility of drilling, slotting and installing 4 ‘reducers’ – but I am definitely not a ‘handy man’ & I have nothing like a bench vise to hold the reducer(s) while I drill & slot them. But perhaps, if I have not annoyed my across the street neighbor by Saturday, he’ll allow me to use his.

If that does not work well, I may investigate the other ‘solution’ I’d seen dealing with drone in a different system – finding someone to add resonators ahead of the rear axle.

Again, I did read every post I could find about this system before I decided to buy them, knowing that there was still some risk of some drone at some highway speeds. Based on all of those posts, I never expected anything like this situation.

( sigh )

Those who believe I received just what I deserved, please line up starting over here.

Those who believe I will end up paying to have the OEM system re-installed, please vote by checking here.

Those who may have been still considering this Flowmaster system and learned something – best of luck!

YMMV.
Anti-flame suit on.
- Ray
Planning to try to capture a couple of driving clips before more advanced exhaust system surgery this weekend . . .

= = =

From the flowmaster web site:

“2005 - 2007 C-6 Corvette American Thunder Kit Quad Tip

Special 50 Series™ Mufflers
Deep Exterior Tone
Little interior resonance <<<<<<<<< harumph!!
2.50" Mandrel Bent Aluminized tubing
Stock Factory Style Hangers For Ease Of Installation
Fits '05-'06 Corvette C6 coupe and convertible (not Z06)
3.50" Embossed Rolled Edged Double Walled Stainless tips


Also, articles like this one suggested to me that Flowmaster did understand & would have made a good faith effort to minimize drone when developing the C6 system. . .
RE: Flowmasters \ drone on a Mustang GT V8:
http://www.fordmuscle.com/archives/2005/03/05Mufflers/

shortski

Flowmasters AKA Dronemasters

Try switching to GHL I love mine. 2005 A4 Z51 Vert and I think they're on special

http://forums.corvetteforum.com/show...18&postcount=1

Heres a sound clip:

http://www.youtube.com/watch?v=8Fyk45P9ZZ4

Indy-hp

I'm sorry the Flowmaster axle-back did not work out for you. I considered them for my C6, but my son has a Flowmaster system on his F150 that is too loud for my taste and drones too much on the highway even for a 22-year-old, so I passed on that system for my C6.

I am continually amazed at how different people will feel about the exact same exhaust system. One would think loud, obnoxious drone would be equally apparent to everyone, but for some unexplainable reason, it isn't.

For what it's worth, it sounds like you are looking for the system I got, the Magnaflow 15886 axle-back, and I am very happy with it.

mkiv808

I have the Flowmasters too and am selling them. Too much drone. Not a bad sound, just too much boom. I like higher frequencies in my exhaust sound. I don't find them *that* loud though, not like Stingers or Bullets, and I think they're a good inexpensive alternative to those.

rothchilds

exhasut is definately a subjective sound. I have the 2 tips and love them. Best advice for anyone is to try and hear a system before purchase, or be willing to spend some dollars on trial and error.

jdurhan

Sounds like a set of Corsa sports would be more to your liking, I love mine 0 drone.

jklarkpimp

quickride

The bottom line when it comes to exhaust systems is to HEAR THEM FOR YOURSELF BEFORE YOU BUY.
It is simply amazing to me to read the originator's comments. I've had the Flowmaster system on my car now for a year and I have absolutely no issues at all. I don't think it is loud at all and neither does my wife. Believe me, she would tell me in a heartbeat if she thought the car was too loud. I have no issues with drone and my car does not disturb my neighbors at all. I should point out here that I have the A4 transmission and the originator has the A6 so there's a slight difference in gear ratios. Maybe that accounts for a difference in sound levels.

I can't stress enough that since all of us have different hearing, requirements, and perceptions, that you do whatever you can to hear a system on a Vette before you go out and get your own. That includes taking a ride in the car on the street and the highway.

I must say that I find the Flowmaster system to be about the most toned down system out there. I visited a Corvette club and took rides in cars with Corsa, Borla, and SLP, systems and every one of them was louder than my Flowmaster. One of cars I rode in had 'Bullets' and it was so loud it just about turned my brain to jelly. The owner admitted his car was very loud but he loved it that way.

I'm sorry to hear the originator is so displeased. Good luck with your next move for an exhaust system.

RICH 28

I have them and I think they are not loud enough.

CHASLS2

I was thinking of buying a used Flowmaster catback for my 06 A6, but now i dont know. I need to find someone with the same car as mine with the Flows installed and take a ride.

rothchilds

best advice there is. What one person likes another will hate, that's why there are so many choices

Larry B.

Just a little note here. I did have to play around with the hole sizes and number of holes to get the right sound. Also the depth you insert the reducers also makes a difference. I also used some Dynamax sound deadener in the rear under the carpet. If it weren't for the inserts I made my flowmasters would have been in the trash due to the undearable drone inside.

SavannahVette13

anyone want to sell them for cheap?

twfreightman

rayainsw

“taking a ride in the car on the street and the highway.”
And
“The bottom line when it comes to exhaust systems is to HEAR THEM FOR YOURSELF BEFORE YOU BUY.”

The largest gathering of Corvettes in my area each year ( AFAIK ) is the Petit LeMans each Fall. And I did try very hard to convince \ entice anyone to do exactly that. Here is one post I made then:

<<<< I will be at Road Atlanta on Saturday.
I have a 2007 Coupe w/A6 on order.

I will PAY ( actual US currency !! ) for your gas or your breakfast or whatever for a ride in a C6 A6 with either an A6 specific aftermarket exhaust or a Flowaster part# 17427 ( quad tip ) system.
Seriously.
I will meet you outside \ before the event begins.
Email me at ( my login here ) at AOL dot com?
Please?
Thanks,
- Ray
Seeing this as one of few opportunities to “try before I buy” . . . >>>

No responses. ( sigh )

quickride

For me, getting multiple rides was easy. I went to a Corvette meeting and afterward, asked any members I saw with other than stock exhaust systems to give me their thoughts. Every single one of them jumped right into their cars and started them up for me to hear. When I asked about the sounds levels on the highway, the first guy said: "let's take a ride". When we got back, there were another two guys willing to give me the same ride so that I could compare all the systems, Borla, Corsa, and SLP.

meaniam

its a thought but i dislike cross overs (cross pipe) on the classic muscle car. as i feel it ruins the sound. takes a lopey idle from sounding good. to canceling the sweet sound by maybe bouncing around. i wounder how the aftermarket exhast would sound without the cross pipe. and i wounder if the tips were pushed out an extra 1/2 to inch. wheather that would avoid the interior noise?

rayainsw

Links below.

Again:
Flowmaster 17427 quad tip axle back.
No other modifications.
2007 C6 Coupe w/A6 trans.

A few comments first on the clips:

1 – I do not currently have access to a true video camera. Thus, these clips were made with my Panasonic FZ-10 digital still camera that ( almost as an afterthought, apparently ) also will record Quicktime clips.

2 – The microphone on my camera did not pick up any of the drone \ overlay that I noted in my impressions. So – the notes & tones that you’ll hear are true and reasonably accurate, but “incomplete” . . .

3 – In the upload the video portion was somewhat compressed. The audio is essentially as originally captured.

The clips:

These are two scenarios I have not see for these or comparable exhaust systems – both from inside the cockpit, windows closed.

http://smg.photobucket.com/albums/v2...11503330to.flv

0 to top of second gear – eased into the throttle, then WOT.

http://smg.photobucket.com/albums/v2...0337cruise.flv

Cruise & mild \ moderate acceleration from 60 to 85-ish.
No drone apparent.
( sigh )

- Ray
Hoping these help someone . . .

Force-1

I have the same 17427 system on my car and am very pleased. I don't have any drone issues and at times don't feel they are loud enough. My wife likes the sound too, and has never complained it bothers her.

Jim_H

I have heard the Flowmasters (dual tip) and I didn't think they were loud or droned. Are you sure you don't have an exhaust leak from the installation?

They're what I'm installing if I don't do headers.