Well like I posted way back when Scoop started this drone/vibration complaint my car does the exact same thing. Luckily I knew it was the exhaust on my car from past experience with the same set up and I just live with it. The car is getting tail pipes this Spring (for sure this time ) though and some other exhaust changes so we'll see what happens. Exhaust tuning/frequency is a very complex issue and the car makers spend large on tuning exhaust to get rid of NVH. Take the 09 and up Hemi trucks. The exhaust is tuned for that engine running on 8 cylinders. Drive one when it shuts down cylinders and the exhaust drone starts instantly. Its not loud but its definitely there. Unavoidable cause the system is tuned for the frequency of all 8 cylinders running. I figure if the Mav dont rattle change in my cup holder going down the road I've done well. Anything beyond that isnt very realistic for a car running flowmasters and turn downs. Keep up the experimenting Scooper. Maybe we can all benefit from it.
Mine droned. I cut the factory exhaust off at the last straight place possible before the pipes merged at the Y. I had about a foot or so of factory pipe off the manifolds, then flex pipe to reducers(reversed) to Flowmaster 40 mufflers, then nothing. I 45 degreed the flex pipe so the end of the mufflers were facing outward. HUGE, horrible awful drone around 35mph. I added 18in extensions off the mufflers so they exited outside the cars bodyline a couple inches...zero drone. Then I ditched it all for sidepipes so now I have zero drone plus sweet sounding sidepipes thus enhancing my manliness.
Getting hot around here, and more and more like boating weather. hopefully, we get a couple more cool fronts, so i can get out and mess with the car a bit more. Soon it will only be "cruise in the loud car late in the afternoon" season, which will last until October, or so. No work done, since it is too hot and sweaty!
I LOVE 44 degrees! Perfect for working on the car. No sweat in your face, shirt stays dry. Maverick75's downturns appear to be facing outwards a touch. I wonder if that makes a difference. I am supposed to get home early today for an electrician to look at a breaker in my house. Maybe I can crank my pipes to face outwards 15-20 degrees and see if it makes a difference. By the way, I may be complaining a lot, but in all honesty, this drone is only minimally annoying. I am just having a good time experimenting with various aspects of the exhaust setup to see what, if anything, makes a difference. I AM getting old, though, and may soon put on a more quiet setup. Getting REALLY close to 40...
Hey, I just turned 40 last year... My mind says that's not old, but my body is proving that otherwise. One of life's cruel jokes...
My mind is still 21, body still feels 18 (most of the time, but looks MUCH older!). All the kids I work with think I am old...
Here's another pic: I measured wrong the first time and the muffler was hitting the drive shaft. So i had to bend the passenger side down a bit. It didn't look symmetrical, but eh it worked lol This was my third time welding anything when I was 18, and i ran outta gas midway through... but the whole thing ended up coasting me $60(including the mufflers).
Mine are slip fit, so I can crank them outward like yours, and use the hanger bolt to hold them that way. may try it this afternoon if the electrician gets here at a decent time...and leaves at a decent time.
Cranked out the mufflers as much as i could without them touching floorpans, got maybe 20 degrees out on both of them. Did not notice any drone reduction. Or even any movement of drone rpm. Any other quick experiments before I give up?
can you point the tips towards the center of the car. maybe at about a 45-60 degree angle to the ground. ive heard a theory that the sound will hit and cancel some of it out.
