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Discussion Starter · #1 · (Edited)
I figured out how to keep the stock resonators on the wagon. This week I installed the Clear Image Gen II headers, high-flow cats, a Pypes X-pipe, and Dynomax mufflers.

The guy who was helping me used an angle grinder to cut the factory mufflers from the over-the-axle pipes without damaging the pipes. I had to grind off a weird stopper on the tops of the pipes, that looked as if there used to be a hanger there. I needed to slide the pipe into the adapter all the way up to the curve.

To go from the 2-1/2" outlet of the mufflers to the 2" pipes, I used ROL brand #617566, 2-1/2" OD to 2" ID, 4-1/2" long, adapters. I got them as an special order at O'Reilly's Auto, who stock parts by ROL.

There was only enough space for U-bolt clamps. The adapters had to be slid well inside the muffler, and I had to make sure that was about an inch left for the clamp.

Everything slid neatly together.
 

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Sounds good. Photos of this would be nice to see. U bolt clamps on each end of the adapter?
 

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Sounds interesting.....but I'm confused what this has to do with the resonators. What you did sounds like replacement of everything before the resonator. Was your goal to keep the resonators and still have good sound and no drone? Just curious.
 

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Discussion Starter · #4 · (Edited)
That's it. I was looking for a better flowing exhaust, but I wanted to keep the stock resonators to reduce drone and keep it as quiet as possible. Also, the over-the-axle pipes on the wagon are complicated and expensive. Since I wanted to keep the resonators, it only made sense to keep the OTA pipes. Here in the desert, exhaust pipes never rust out.

The reasoning is that the exhaust gasses should be fairly cool by the time they exit the muffler, and wouldn't need the 2-1/2" pipes.

I know that a couple of other people on the forum have done this, but no one explained how they did it. I'll take pictures the next time I jack up the car, probably this weekend.
 

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Ok, that's what I thought. When I added turbo mufflers to my wagon, I had to add reducers to match the stock exhaust pipes. I also cut my resonators myself and welded/clamped a piece of straight pipe in (Autozone had an exact length pipe that fit in place), so I still have my over the axle stock pipes and the stock turndown end pieces......looks all stock. No drone.
 

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Discussion Starter · #6 ·
Here's a picture. You can see that I only left enough of the reducer showing to fit a clamp onto it. I had to push the small end of the reducer as far as I could over the OTA pipe.

 

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Are the resonators a stright shot through or are they like another muffler?
Typically resonators, including our stock ones, are straight thru designs.
 

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Is there a rule of thumb as to how much the exhaust really cools down, and how much smaller you can really go on the rear pipes without hurting flow? It just seems that smaller is smaller, but maybe smaller is ok way back there?????

I have the stock OTA pipes on my Wagon after the Dynomax VT's and Pypes X, and I always figured the OTA pipes were killing my whole exhaust flow.........

Why didn;t you get the VT mufflers? They are almost silent at cruise speed with no resonators, and NO cats! They are awesome!
 

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I used the Pypes Street Pro exhaust for the Impala SS and cut the Imp/sedan ota pipes behind the axle and welded 2 1/2" X 2" reducers to the stock wagon tail pipes with resonators. So I have 2 1/2" pipe going over the axle, and following the back side of the rear axle with the reducer in that straight piece. I'll get some pics. in a few days.
The only difference between the sedan ota pipes and wagon pipes are where the pipes have to snake around the gas tank and fuel filler pipe. I figure the biggest restrictions in the stock exhaust besides the mufflers, are the 2"ota section, and the intermediate pipe right under the trans. cross member.

This was a lot cheaper than the aftermarket ota wagon pipes, looks stock, and a lot less drone.

Mike
 
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