3" exhaust

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1969dodgedart

Big Block 440
Joined
Aug 15, 2012
Messages
275
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Location
Ontario,Canada
I'm looking for suggestions for full length 3" exhaust coming out under the bumper ? 440 with 727 , tti headers .
 
You just need to find a exhaust shop close to you that can do it.
My friend can do a trick tig welded stainless exhaust but it's a long way to go for you.
 
Summit offers a house brand 3"header back kit for 67-74 a-bodies with headers, with or without mufflers. I bet jegs does too. Sum-680145, or same number with nm for no muffler.
 
I have a 10 Second 440 68 Valiant thru
the exhaust with TTI headers
I replaced 2 1/2 exhaust with 3 Inch
both Mandril bent pro systems
NO difference in performance@ track
 
It's extremely tight going over the rear axle on A-bodies. Pypes developed a system that is 3" X or H 3" mufflers and then 2.5" tailpipes. The system allows the engine to breath way better while not having fitment issues or spending the money for custom exhaust which if not done right is not even as good as 2.5" mandrel bent.

67-73 Mopar A-Body Hybrid 3" to 2.5" Crossmember Back w/ X-Pipe System (SMA30)

Feel free to PM me for a A-Body Only member price.
 
I put turn downs before axle on both systems = too restrictive going around axle!
Quickest, cheapest and easiest! However, it's also the loudest and a lot of dirt gets kicked up. Whatever way you go It's a trade off that the owner has to be most comfortable with.
 
For my SBM 68 Barracuda, I bought the TTI mandrel bent 3in/3out H-pipe kit, with Dynomax 3-pass mufflers. I had no fitment issues even with the rear end narrowed and the springs offset to allow 325/50-15s in the stock tubs. I won't say there was "lots of room", but rather "more than enough" . Mine are turned down at the rear bumper. Stock gas tank. No drone. but 72 pounds with the muffs. Also, not too loud or too quiet with 11/1 Scr and 178 to 188 psi.
But they do scream at WOT, starting at about 5000.....
I have been pulled over several times since 1999 but never was noise mentioned.
Oh yeah, almost forgot; my car is lowered quite a bit; K has been down at 5.5 off the tarmac but currently closer to 6 inches, and car does not have much rake.
 
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It's extremely tight going over the rear axle on A-bodies. Pypes developed a system that is 3" X or H 3" mufflers and then 2.5" tailpipes. The system allows the engine to breath way better while not having fitment issues or spending the money for custom exhaust which if not done right is not even as good as 2.5" mandrel bent.

67-73 Mopar A-Body Hybrid 3" to 2.5" Crossmember Back w/ X-Pipe System (SMA30)

Feel free to PM me for a A-Body Only member price.
Cold case , shoot me an email address. Thx pm
 
For your streeter;
Is 3 in/3out needed at my 430 hp? No. But big pipes have other advantages. If you don't have to spend more to get them installed.
> 3inchers, NOT at WOT, offer;
1) 20% more surface area for cooling the gasses. and
2) 20% more volume ahead of the mufflers, to dump that hot exhaust gas into, so
3) by the time the hot gasses get to the muffs, they have cooled off considerably, and they have condensed into occupying less space, so
4) have lost a lotta energy, so
5) by the time they come out of the end, they are relatively cool, relatively dense, and relatively quiet, having lost their hi-frequency tones . This makes the car pleasant to drive behind. But
> 3 inchers for cruising;
6) more importantly; at Part Throttle, while cruising, the engine doesn't even know the pipes are there, and so 30mpgUSg is possible, with the right combo.
7) Furthermore, your headers will run cooler, so the chambers may also run cooler, and be better able to survive running a lil more cylinder pressure.
> 3 inchers, at WOT;
with those big pipes, the headers work almost like the pipes are not there;
the inertial tuning of the headers work, and
the scavenging works, and
the overlap cycle works.
and if you tune for it, you don't have to drop them at the track,
and your streeter can run a little less cam, allowing your engine to produce a powerband that works with your transmission, to stay on the pipe, putting down the same or more average power in second gear, and allowing a lower stall.
3inchers for 400hp;
But no, a typical streeter will never NEED the capacity of 3in/3outs. But I have never been sorry I got them. Well, except for the 72 pounds. But No biggie, I ditched the rear seat which nobody ever sits in anyway, and broke even to no system at all.
 
Custom made

Go 4 inch. Step up the game.

A9D5C490-06FE-4903-A9D0-C83ADD34F3B1.jpeg
 
This is a full 3 inch exhaust from the fenderwell headers back under the car to an x-pipe to the Dynomax turbo mufflers in the stock location, to 3 inch TTI tail pipes, with a relocated fuel tank strap on my 66 Dart. TTI big block headers are under chase headers and should be a little easier to make up the front pipes out of a universal exhaust kit. I used a universal x-pipe kit and a couple of extra bends and a length of straight
0613081252a.jpg
pipe to make mine. Not a good picture, but it shows that 3 inch fits with plenty of ground clearance with 1 inch lowering springs.
GREGG`PICTURES 001.jpg
 
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