Dumps behind axle?

[Fett]

I have Ford Racing shorties, a UPR X-pipe (I don't like to admit that), and Superturbos dumped at the muffler with just a set of turn-downs.

At idle it drones inside the car, while driving they sound great. I dumped them because I simply don't have any room for tails, nor do I want them. So I was thinking of cutting off the turn-downs and having a set of pipes cut after the axle, so the they would dump right behind the axle.

Anybody have any ideas how it will effect tone or noise before I have it done?

 

[5.0Droptop]

do you mean running the pipes over the axel and dumping them there?

 

[Aliate X]

Well having it go over the axle defeats the purpose of dumps, but yes it will make a good difference in drone and such.

 

[sivart]

thats what the stock pipes do...dump like right b4 the bumper

 

[5.0Droptop]

FETT, I just got thru reinstalling my flow master is place of my macs. The macs were dumped before the axles. I took your idea and ran the flows over the axle and dumped them on each side of the gas tank at the front of the tank. ( they originally went all the way back to the gt bumper I had to cut them to get them out)

It sounds so much better inside the car and I love the way my american thunder 40 series sound compared to the macs.

 

[SVT32VDOHC]

MY 91 notch is a MAC catback and dumped over the axle. That is where the tails are supposed to bolt up. I left them off because I got the catback free...but it was off a GT, so the pipes were ugly turn downs.

Well, I ended up loving the sound, so I left it. It is very different. My Dad doesn't like it though, he said it just sounds like an old junk car that needs a muffler ...but I have had multiple people tell me otherwise.

 

[Fett]

Yea that's what I am thinking of doing. I am pretty sure my old mufflers/tips are laying around work somewhere. I figured I could use those and just cut off the tips so they dump just after the axle hump.

My only fitment issue was with my tires, so I figure dumping them there would help get rid of some of the drone, but still be free from my tires.

 

[GTOreturns]

Thats how big block Nova's came in the late 60's early 70's. It's a great idea and would have to be legal in my eye's.

I would love hear hear a clip of this set up at WOT.

 

[SVT32VDOHC]

The only thing I don't like about it is all the hot exhaust dumps right above the gas tank! I don't think a flame could get that far back in the exhaust but I just hope it never happens!!! IF you cut yours, cut them at an angle furthest away from the gas tank. I have no choice because mine are Tru-Fit style so that is where they bolt up.

 

[85_SS_302_Coupe]

MAC cat-backs have part of the tail pipe section welded to the back of the mufflers and this goes to just over top of the axle where the rest of the tail pipes bolt up. I ran a GT this way without the tail pipes bolted on for a long time and the difference between full tails and this is very little. You will get a lot less drone but depending on the mufflers there's really nothing you can do to get rid of it.

 

[GTOreturns]

If I had a GT that's how I would run the exhaust.

 

[UnderdogGN]

Ive seen this done before with great results.
Angle both your turndowns at a 45 degree angle toward each other. This cancels out sound/drone.
just an idea

 

[85_SS_302_Coupe]

Ive seen this done before with great results.
Angle both your turndowns at a 45 degree angle toward each other. This cancels out sound/drone.
just an idea

Yeah, any time i run dumps i use clamp on dumps so i can play around with the angle. I like to angle them to the sides for extra noise pollution

Most of the time i don't run dumps at all.

 

[5.0Droptop]

I just came home with the wife and kids. We drove the stang. I got no complaints from wife or kids so It must be pretty good. It sounds really differnt. I have had off road h pipe with american thunder cat back on the vert and it had a nice typical mustang sound.

The off road prochamber with the american thunder mufflers dumped over the axle has whole differnt sound.......

 

[LiquidGT]

I remember an old MM&FF article I have about a project Mustang GT road racer with dumps over the axle, iirc they didnt have the turndown tips, the hot gasses would blow directly on the tank. Anyway they were out on the road course when fuel started spewing out of the gas cap. They got flagged down, it turned out that the exhaust gasses were blowing on the tank and caused the fuel to boil, it also melted the rubber undercoating on the chassis. Being a fox GT made it worse because the bumper kept all the hot gasses under the car!

 

[Fett]

I thought of that, so I would make my turn-downs exit lower than the gas tank.

 

[5.0Droptop]

I thought of that, so I would make my turn-downs exit lower than the gas tank.

Thats what I did, and I made the angle out some.

 

[iLkYsPoNy]

I have my flowmasters dumped right before the axle, at an angle towards each other facing down... if that makes sense. Here's an example of the sound, sorry for the lack of quality, its from a cell phone.

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