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Dynomax 17748 Muffler Flow Direction???


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10:27 PM
Mar 26, 2017
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So, Idk if I'm the dumbass, the mechanic or, the tech guy at Dynomax or, all the above for that matter. Had a set of these put on the 71 Tuesday, 2 1/2" from collectors to out back. I thought they were a bit quiet for what they were when picking it up but, I never really looked but briefly and mostly just listened to it and trusted it was sealed and solid as he said (dumbass me there). Drove home 15 miles, 5 on the highway. Pretty quiet. Still seems strange. Large plume of smoke out the back when I let off after a little throttle a couple times. Not normal... Well looking.at things in the driveway after getting home, I notice the outlets are at center. It says specifically on the box itself etc that they are center inlet offset outlet. So, technically they are backwards, right!? I also noticed in the driveway while idling in gear, both mufflers are now making a rapping sound from inside. These are not chambered but, both are making noise like so inside. It is a metal to metal rapping or smacking tinging like noise. I had someone put the car in gear and E braked as I crawled under to see what was hitting. Nothing is hitting and the noise is clearly coming from inside both mufflers. This is within several hours of being installed. Called a Dynomax tech. He said "most turbos style mufflers are directional "....well I didn't buy MOST mufflers I bought THEIR mufflers and asked why they say center inlet and offset outlet if thats not the case. To me, that specifies... I got nothing other than he has a lot of calls and never heard of this. Zero help. Take em back were I got em he said. (Exactly how long are we to keep the boxes etc!?) My next question is still, WTF???
Mechanic said bring it up Monday and swap them around that it shouldn't matter. I feel it does considering what's going on. He claimed easier to mount. If that's is the case why would even TTI sell them with a kit and list them as inlet and outlet the same way, center in, offset out. It's a mere half bend more or so on each pipe away from the driveshaft (which he claimed the would hit mounted opposite). At least he is working with me as he should but, I feel jacked around from both sides. It's bad enough most **** is made by the CHICOM's, not worth **** new and customer service is virtually non existent unless calling for insurance or cable. Its a GREAT start for summer thus far! Thoughts?
Most all mopar systems are offset inlet and center outlet. Keeps the muffler away from the driveshaft on the inlet side.
Number one question asked at auto parts suppliers in the 70's......... WHICH WAY DOES THE WOODPECKER POINT?? :poke:

Looks like they are reversible. Maybe you got a bad one?? None of that explains the smoke tho!!
Funny how far a little misinfo can go....he works there. I dont get it. Nonetheless ended up being that one of the two is bad inside and the part store is replacing it. Surprised at that too anymore. Thanks for the replies
I’ve had two Dynomax 17747 Super Turbo mufflers fail internally. One gave no evidence of failure, except on the time slip. The other would give a slight metallic rattle occasionally, and also killed et.