Exhaust Droning?...Advice Needed

[00blacksixer]

Hello all,

I have a 00 automatic V6 with a newly installed exhaust. Its a true dual 2 1/4" cat back system with 40 series flowmasters and a custom fabricated H pipe. When the car idles at say 800 rpm, the whole car vibrates and shakes horribly bad. When I give it a little gas and get the rpms up to about 1000 rpm or so, the car runs smooth and doesnt vibrate or shake like it did at lower rpms. A friend of mine suggested that my problem was "exhaust droning". I was wondering if anyone out there has experienced this type of problem. It would be great if someone could tell me what it is caused by and how I can fix it.

-Thanks

 

[ChingonStang]

First, True Duals actually means no h or x pipe in the setup. At least that was what I was told. Second, the exhaust drone actually refers to the common 2k rpm drone most Flowmaster exhaust produce. To elminate some of the drone, you can dynamat the floorboard of your cabin. Flowmaster 40's Deltaflow is also suppossed to lessen the drone. But I would just get used to it. Look at it this way, imagine the drone from a V8. As for the vibration, your stang is idling too low, increase the idle a bit closer to 1k rpm and that should fix the issue. Congrats on upgrading to duals from that crappy single piddly stock exhaust.

 

[77sleeper]

get a resonator placed upstream

 

[stangin99]

first dual exhaust is dual exhaust...has nothing to do with having a crossover or not. by that reasoning pretty much all v8's dont have true dual exhaust. You're talking about having straight pipes.

And is it a vibration or noise? Check if any pipes are hitting the underbody. If its noise, you just have to get used to having a louder car.

 

[Mach1Run]

True dual exhaust is what GTs have and yes its a dual if it has an H or X midpipe. Most V6s have the Y midpipe. there are some folks who put true duals on V6, in fact I gave my takeoffs to someone in town for just that when I put my catback on.

 

[00blacksixer]

Thanks for the advice. It seems as though it is more of a vibration than a noise. I think the most simple way to fix the problem is getting the car to idle around 1000 rpms. How can I get it to idle at 1000rpms constantly without having to keep feeding it gas?

 

[PonyJoe]

I had the same problem, except it only happened when I started the car. It ended up being one of my mufflers was vibrating on the underbody. A few changes, and tighter bolts fixed it real quick tho. In fact I have to do it again, it sounds like one my bolts may be loose and is rattling at idle also.

 

[mhjo]

Best way to get rid of drone:

1. Move one of the mufflers 2-3" forward or backwards (compared to the other) so that they have an unequal distance from engine.

2. Install a H-pipe
3. Install a resonator behind each muffler.