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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Glennman on September 22, 2019, 09:18:19 PM

Title: Maximizing Muffler Output
Post by: Glennman on September 22, 2019, 09:18:19 PM
In bouncing off the thread from a while back about the gentleman who had the top of his MCI muffler top cut open, baffles removed or otherwise opened up, then welded back shut, and how it gave him more horse power and helped with his overheating issues, I'm sharing my experience on this.

I commented on how I drilled a 4" round hole next to the tail exhaust of the muffler to open up the flow. Well, I just today welded in the new 4" elbows (one in the new hole, the other onto the original 4" outlet). It hardly raised the noise level at all, but doubled the output. The air feels like it comes out at the same pressure from both holes. Sounds good, runs good. I drove a bit, but didn't notice any measurable difference, but I'll be heading over the mountains next weekend. I'm hoping I'll have the same result as the other gentleman.
Title: Re: Maximizing Muffler Output
Post by: Scott & Heather on September 23, 2019, 05:04:11 AM
Or you can just throw on a stainless aero and call it a day :)

https://youtu.be/w4nI3y-YXiE
Title: Re: Maximizing Muffler Output
Post by: muldoonman on September 23, 2019, 07:17:01 AM
Sounds good, Scott. As soon as I get all the other work on the bus finished that will be next in line.  My 8V92TA has about 95,000 miles on it and is ready. Is that the   AT3535 or the medium AT5050XL??  8)[img]
Title: Re: Maximizing Muffler Output
Post by: edvanland on September 23, 2019, 09:52:29 AM
I was in on that muffler cut out then we just took that big muffler off my MCI & with a 8v92 and put on a resonator and straight pipe out the side. What a difference runs better cooler and pulls the hills better wish I had known about that long time ago.
Title: Re: Maximizing Muffler Output
Post by: Glennman on September 23, 2019, 06:43:17 PM
If this change I made makes any difference, I might consider the straight pipe with resonator. I have about $65.00 into my 2 tailpipe elbows, so no big thing to rip it all out and go all the way. Thanks all!!!
Title: Re: Maximizing Muffler Output
Post by: Lin on September 24, 2019, 12:21:20 PM
Scott, is that your bus with the Aero muffler?  Did you see improved performance?
Title: Re: Maximizing Muffler Output
Post by: edvanland on September 24, 2019, 02:47:26 PM
You will need the elbows so no waste of money
Title: Re: Maximizing Muffler Output
Post by: Glennman on September 24, 2019, 10:45:40 PM
The main exhaust off the turbo is 5+ inches, and the two tail pipes are 4 inch, so it was reduced down from 5 to 4, not counting all the maneuvering within the muffler to get to the final 4 inch tail pipe. It was quite restricted. If I was to go with a straight pipe with a resonator, I would need all 5 inch parts. But that's ok!

Glennman
Title: Re: Maximizing Muffler Output
Post by: Scott & Heather on September 25, 2019, 09:06:34 AM
Yes that's my coach with the Aero. I cannot remember which one it was. But it fits perfectly. I tried searching my emails for the order but can't find it.
Title: Re: Maximizing Muffler Output
Post by: DoubleEagle on September 25, 2019, 05:48:06 PM
aeroexhaust.com, Model AT5050XL
Title: Re: Maximizing Muffler Output
Post by: Fred Mc on September 25, 2019, 06:15:08 PM
So would this work with an 8/71 in a PD 4106 .It would be nice to get rid of that big muffler in the engine comparment. It would also reduce the heat in the compartment. What are the downsides to this.
Title: Re: Maximizing Muffler Output
Post by: DoubleEagle on September 25, 2019, 07:06:30 PM
I don't know the 4106 setup, but it is still a 8V71, so either you use two four inch resonators  or one 5". It will definitely take up less room, be a little bit louder, but there should be less heat, especially if you wrap them.
Title: Re: Maximizing Muffler Output
Post by: Fred Mc on September 26, 2019, 11:00:20 AM
Where is a good place (. I.e. Reasonably price) to buy the pipe/elbows?

Thx.
Fred
Title: Re: Maximizing Muffler Output
Post by: TomC on September 26, 2019, 11:07:45 AM
Anywhere the shop does big rig exhaust.