Exhaust question

[brianstrange]

I have a small Class C. The PO installed a new muffler, but left the old tailpipe, which needs replacement. The current tailpipe exits at the Pass rear corner, right next to the generator. With a new tailpipe going in, I was wondering if exiting behind the pass rear wheel, is a better location. Just looking to keep it simple.

Thoughts?


Thank You

[wgander]

I don't remember where my original tail pipe was located, but when I had the muffler replaced, the exhaust pipe was relocated and now exits just aft of the entrance steps on the passenger side. I have not noticed any fumes entering the coach in the seven years and 50,000 miles since the change.

[brianstrange]

rvten wrote:
A good muffler shop can custom make what you want.

And what I want, has yet to be determined...... Maybe this should be in the tech section?????

Sometimes I wonder if people actually read the posts. I'll assume that nobody here has run into this question, or has any real world experience on the subject. Thank you for trying. VROOM VROOM

[rvten]

A good muffler shop can custom make what you want.

[brianstrange]

j-d wrote:
Behind wheels was fine. At first I didn't think it would clear our electric step but it went between the mudflap and the step. We tend to drag the rear once in awhile, so I wouldn't go straight out the back.
I'm nobody's physicist, but I suspect exhaust would be sucked back to the rear of the coach as badly or worse coming out the rear than out a side.
What year Dodge? No Catalytic Converter, I take it. Our Ford E350 was 1983, and either that year or perhaps 1984 was the last to have a cat on that chassis. Our FM kit was for a couple years later and was billed as a "Cat-Back" setup. It came with an extra piece of straight pipe to make up for a long wheelbase chassis and that was enough to make up for the non-existent cat and the damage I cut off of the crossover pipe. Turned out to be a sweet setup, and you should be able to do the same.
What are you using for a muffler? As I recall, I put Walker 20475 on the Dodge. It was 2-1/2" in and out, and I think there was a 3" version, plus a welded and maybe a stainless.
Just be sure the muffler you choose is the true "size" all the way through. I've seen some mufflers with 2-1/2" "necks" to connect to pipe, but you could see where they were reduced to 2" entering and leaving the muffler itself.

93 Dakota 318 Cab. There is a cat and a new stainless muffler. The tail pipe was re-used, but is now past it's life.

[j-d]

Behind wheels was fine. At first I didn't think it would clear our electric step but it went between the mudflap and the step. We tend to drag the rear once in awhile, so I wouldn't go straight out the back.
I'm nobody's physicist, but I suspect exhaust would be sucked back to the rear of the coach as badly or worse coming out the rear than out a side.
What year Dodge? No Catalytic Converter, I take it. Our Ford E350 was 1983, and either that year or perhaps 1984 was the last to have a cat on that chassis. Our FM kit was for a couple years later and was billed as a "Cat-Back" setup. It came with an extra piece of straight pipe to make up for a long wheelbase chassis and that was enough to make up for the non-existent cat and the damage I cut off of the crossover pipe. Turned out to be a sweet setup, and you should be able to do the same.
What are you using for a muffler? As I recall, I put Walker 20475 on the Dodge. It was 2-1/2" in and out, and I think there was a 3" version, plus a welded and maybe a stainless.
Just be sure the muffler you choose is the true "size" all the way through. I've seen some mufflers with 2-1/2" "necks" to connect to pipe, but you could see where they were reduced to 2" entering and leaving the muffler itself.

[brianstrange]

j-d wrote:

I don't think I'd suggest you exit the exhaust midship (forward of the wheels) on a motorhome. There are too many places in the body for exhaust to leak in as you drive.

I was thinking the side, behind the rear tires, but before the generator, or, straight out the back. I'm having it custom fitted, so I'm not worried about boxed parts. A custom bent 1 piece runs between $125 & $175 installed.

[j-d]

Our first Class C had a cobbed-up exhaust system and a bent crossover pipe. I found where Flowmastermufflers.com listed a complete kit. When it arrived, the discharge (oversized polished stainless tip - nice!) was behind the wheels instead of near the bumper. It worked out fine.
I was ready to have a local muffler shop make a "custom" exhaust when I found I could get the kit for about the same price. I had to put in a day of install time but the FM kit was quality goods. Full 3" pipe, aluminized, with "mandrel bends." That means full size all the way through, no kinky corners. And the muffler, called "Big Block II", was a heavy, massive, all-welded unit.
The reason the Chassis Brand matters, is in some cases you can order parts fitted to the exact application. In a Class A gasser, the most common parts will be the Chevy P3x group, then the Ford F53. Exact parts for Dodge are going to be rare. I used to fix school buses. There were "over axle" pipes that came in what I'll call "halves." You clamped them together over the axle and the two-piece approach let you change the side-to-side spacing. Still an awkward compromise.
I don't think I'd suggest you exit the exhaust midship (forward of the wheels) on a motorhome. There are too many places in the body for exhaust to leak in as you drive.
Oh, all the Class C kits MF had were single with 3" pipe and muffler. Some of the Class A kits were duals. If your Dodge has the 440 engine, I'd say go to 3". You won't need duals. I think the C kits were single only because there's so much stuff under the body in the way. We had a 460 Ford and single 3" was plenty. 2-1/2" would work for a 360. We had a Dodge van with 360 and used a medium truck muffler with 2-1/2" in and out, with that size tailpipe.

[brianstrange]

rvten wrote:
You do not say what chassis or year. Ford or Chevy?
My 08 E450 Ford. The exhaust comes out pass side mid way on frame.

I'm not sure why the chassis would matter here. It's a simple question about rear or side exit exhaust. Please tell me why this matters so I can make sure I'm considering everything. For the record, it's a Dodge.

[rvten]

You do not say what chassis or year. Ford or Chevy?
My 08 E450 Ford. The exhaust comes out pass side mid way on frame.

[RJsfishin]

I remember my old class c, I installed headers and turbos, and exited just ahead of the rear duals. Wow did it ever sound good pulling my 19 ft boat up Donner Pass !!