Fox Another Exhaust Question - For Stock Gt Fox

My wife has a 1990 GT convert, which serves as a weekend/errand toy for her, and it's completely stock except for the tail pipes on it. It's in great shape, and we really want to keep it close to factory condition.

I went to get it inspected the other day, and both tail pipes are rusted with holes, so they failed it. we've talked about swapping out the catback anyway, because whoever replaced the pipes previously installed tail pipes which exit under the ground effects, and this has caused cracks in the ground effects paint over the years (when exiting a steep driveway, the pipes hit the road and contact the ground effects).

So we want to replace the catback with something that is not too loud, but adds a bit of rumble; and also want to go back to the stock style tips with the turndowns just behind the ground effects at the rear.

So I'm looking for a good catback (preferrably stainless) which won't drone at any RPM, and has just a bit of rumble to it, but not really loud.

The Flowmaster 50 series seem to have the right level of rumble-to-loud ratio, but I'm concerned they will drone. To prevent drone, do I need 2 slightly different sized mufflers? I read somewhere that a manufacturer of catbacks did this to prevent drone ....

Here's a pic of the back. As you can see, the rear bumper and ground effects need repainting, but we're going to wait until the tail pipe issue is worked out.

IMG_1405.jpg


And here's an old pic of the car when we 1st brought it home, before a detail and the new top was installed:

Fox_Convert.JPG
 
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If you don't mind having one made up, I just installed a set of 2013 Mustang GT take off mufflers on my car. They're 2 1/2" and will support well over 400hp.

They're a little bigger than Fox Body mufflers, so you'll have to get a muffler shop to make up something custom for them to fit, but they're high quality stainless steel, completely drone free and most importantly, can often be had for about $50 a pair. :nice:
 
Thanks Brian, definitely an option. I don't mind an exhaust shop fabbing something up, although I called a local shop and they only work with aluminized piping. I'm sure I could find another one who can do it in stainless though.

I'll have to listen to a stock 2013 1st though. I wonder if they would add any rumble at all to a completely stock 302 (stock cam, stock headers, stock H-pipe w/cats, etc ...)?

The no drone is great though!
 
Thanks Brian, definitely an option. I don't mind an exhaust shop fabbing something up, although I called a local shop and they only work with aluminized piping. I'm sure I could find another one who can do it in stainless though.

I'll have to listen to a stock 2013 1st though. I wonder if they would add any rumble at all to a completely stock 302 (stock cam, stock headers, stock H-pipe w/cats, etc ...)?

The no drone is great though!
The 2013's do sound nice, but since they're a 4V modular engine, they'll sound quite different than the 5.0L OHV engine in your wife's stock mustang. The truth is, all aftermarket mufflers are going to present some measure of drone. Som will be louder than others, but I have yet to see any aftermarket muffler eliminate drone completely.

Even the 50-series You were considering will have some measure of it.
 
Just thought I'd post an update to this.

I ended up buying:
Total cost was $327.69 after taxes and shipping.

I removed all the old stuff myself, installed the mufflers loosely, then took it to an exhaust shop. I needed them to expand the 2.5" tips slightly, so they would fit over the 2.25" outlets of the mufflers. I know they're supposed to go inside, but it was much easier to expand the pipes instead.

So we expanded the pipes, installed them, aligned everything up, then welded all the connections. the car sounds great! There's a nice, subtle, deep rumble at idle, but it's not very loud when getting on it. Also, there's no drone at all in the cabin. I assume this is due to the different size mufflers for the passenger's vs. driver's sides.
 
The wife is out running errands right now in it, but I'll try to get some pics and a video for sound later today.

I definitely did not want to hack up the bumper, which is why I went with the stock style tail pipes. I also do not like the look when the pipes exit under the rear bumper, which is what was on it when we bought it. The previous pipes ended up cracking the rear bumper a bit (vibration maybe? Or skidding the ground on steep driveways?), which I'm not pleased about. Eventually we'll get it re painted and fix it at that time.

The goal here is to return this car to like-factory condition. Next up will be replacement dampers and bushings all the way around. Probably something simple like Sensa-Tracs. I may do subframe connectors as the only real mod, but other than that, it will remain very close to stock.
 
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