Added H-pipe. Just moved the drone to different RPMs.

I have been complaining since I put in my Flowmaster Super44s that the car has a horrible drone at cruising speed (55-65 mph) that at times i thought was u-joints going out, out of balance driveshaft, transmission mounts and tailshaft housing. Well after replacing all of those, I fabricated and installed an H-pipe to try to eliminate the drone.

After welding and cutting to make one in the best available location ( see thread http://mmb.maverick.to/showthread.php?t=76511&page=1) I finally got out to test drive it, and now it still drones, but I just moved the speed of the drone down to 40-50 mph. It starts out with that slow cycling vibration at 40, then it speeds up the cycle until 50, and just after 50 the noise just disappears and it is smooth sailing at cruising speed. Haven't gone above 70 yet, but then I seldom cruise at that speed.

So at this point, I will either sell the Super44s and go with glasspacks, extend the pipes out from under the car, or just learn to get used to it. Or maybe figure out something else that may work...

 

That's why I won't put flowmasters on anything I own.

 

I probably wouldn't do it again. I was "young" when I put them on.

What would you put on in the future, instead of Flows?

 

I exited mine outside the body and it cured the drone 100%.
Then I replaced the whole thing with sidepipes and it is surprisingly quiet.

 

I think with a little group brain power and a few calculators we can get your drone down. Unfortunately, it also boils down to you experimenting, and sometimes that is not fun the fourth or fifth time. Especially when its your driver.

 

Patriot fixes this.

Seriously though, exit the exhaust past the rockers instead of straight down.
That was the miracle that stopped the teeth jarring drone I had with Flowmaster 40s at 35-45mph.

 

Paintank, I agree, I had NO DRONE when I had the patriot side pipes. Only picked it up when I put the Flows on dumping under the car.

The only time I heard the sidepipes was when I was on a bridge and heard the sound echoing back at me.

I loved those sidepipes, except they drug on EVERYTHING!!!

 

I run full tailpipes, with Hooker aerochambers on the 89 5.0 & the Ranchero. The 'stang has cheap ($35) Summit race mufflers, none of them drone.

 

When my Flow 40s dumped down it droned. When I 45ed them and they stuck out past the rockers the drone magically disappeared at all speeds. Still sounded mean, just not deafening.

 

You need tail-pipes.

 

Does this mean exiting out the side of the car in front of the wheels?

I have Cal-Tracs, which makes side-exits difficult, even though that is what I like best...old pic...

 

Pick a spot - out the sides or out the back - either will work.

 

This is my side exiting setup with no mufflers....Had the same set-up on a '66 Stang with a 347 and it was the best sounding car i've ever owned....You have to get them out from underneath the car

 

That's weird. I have 2.5 inch pipe and 2 chamber Flows with an H-pipe. Dumps right before the axle and it sounds really aggressive but no drone. What did I do right?

Steamliner: Did that X-pipe quiet your car a little? I want to reduce the volume just a little and was thinking about a set up like that with mufflers. It looks awesome.

 

On my Maverick it hasn't been run yet but on other cars i've had with it it mellows the sound out and is slightly higher pitched