I have dual flowmaster super44s, and have LOUD droning. A few guys have suggested that I do an x-pipe or run the exhaust out past the bottom of the car. So, I have been devising an experiment. I was thinking of using cheap flexible exhaust hose to tie the two dualled pipes together Siamese fashion, and running the two 2-1/2" pipes into a single 2-3/4 or 3" pipe out the back. If this works to lose my cruising rpm drone, i may do a permanent version of it or do an x-pipe to see if it will lower that noise. Being only a 5.0 +.040, do I need to go over 2.5" on the exit pipe? Trying to keep it cheap, since I will throw it away after the experiment is over.
flowmasters drone. i have 50 series with a x pipe. i used to have them dump at the the rear end. then i put tail pipes on and they still drone. i had 40 series on my old 302 and they droned. on my old fox mustang i had lots of different mufflers. all flowmasters drone. im planing on chaning my current mufflers to magnaflows or super turbos. i know that with the fox mustangs ford put two different size mufflers on them stock to get rid of the drone. flowmaster used to sell there fox kit with different size mufflers but they still droned. i do look foward to the results of your experiment.
But, if you state that they will drone anyways, then i won't waste the money on the experiment. I was thinking of magnaflows, or learning to live with the drone. The problem is the drone at cruise speed sounds like a drivetrain failure about to happen, so it is hard to drive long distances without worrying about a failed u-joint, or whatever. Not comfy driving and worrying all the time, for something that most likely is just exhaust noise. Been doing this for 5 years now with no failures, but still worrying...
Bryant, I will take one for science if you will take one in the pocket book and fork over cash for parts!!! Seriously, though, if drone is inevitable with flowmasters, I will just have to learn to live with it. I was hoping a siamese setup would minimize or delete that noise.
I believe if you are looking for cash for science maybe you can get a grant from the government!!! I think you will have to live with the drone with any of the chambered mufflers. The Flowmaster's made every little loose part an my GTO rattle just to add to the symphony. I replaced those woth 3" Flowtech mufflers and 2 1/2" tailpipes when I went to the 455 and it was worse that the Flowmaster's for drone.
I had that same problem. I switched to turbo mufflers, got ok sound, but no droning...now I can hear my radio, talk to passengers. Flow40's are just too loud.
the corral drone thread incase you feel like reading LOL http://forums.corral.net/forums/general-mustang-tech/496793-exhaust-drone-completely-gone.html My mustang has headers, x pipe, 2.5 flow tubes and 2.5 straight through turbo mufflers. I had a horrible drone right about 2300 cruising around town. I added on 3inch tail pipes to the rest of my 2.5 system and it shifted the drone down a few houndred RPM. Worked good for me and now decent on the cross streets
Interesting reading!! I have the dreaded drone -- I called it resonance. Changed from Magnaflows to Thrush and it was reduced by at least half.
Wow, that dude knows his stuff. GM used a setup like he made on factory duals on Monte Carlo's in the early 70's, never understood why until now.
flowmasters drone...took mine off within 3 weeks of installing them. they made the car sound like it was coming apart...
Interesting, but UGLY! I would rather swap mufflers or add baffles before adding an extra chunk of pipe.
If you put resonators up-stream of the flowdisasters it will take care of the unwanted sound and quiet them down a bunch. I did this on my work truck and it helped alot.
I agree thats why I chose to try different diameter tail pipes to not eliminate the drone but shift the drone to a different RPM. My car only really drones now when I am to low of a useable rpm anyway. I think with a little expirimenting with different size tail pipes you can shift it to a rpm that you don't use anyway, its not eliminated but your barely ever going to notice it. Mine was not expirimenting though, a local mustang guy had an almost exact setup as me and I bought his tail pipes when he went a different route. He did the R&R not me LOL.