ATC110 Home Made Exhaust (Ghetto)

[ATC King]

I bought this 110, knowing the exhaust was missing.

Here's what I done. Some of you older people will know what the chambered attempt was.
https://stainlessworks.net/chambered-round-mufflers
http://ntamc.blogspot.com/2012_03_01_archive.html
https://stainlessworks.net/ford-mustang-gt-2015-exhaust-3-chambered-round-catback
http://www.classicchambered.com/
http://alancolvin.com/store/chambered-exhaust/

What I started with.
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It was too loud and sounded like crap, so I revisited some of the old stuff.


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It's still a little loud, but it sounds much better than a straight pipe. I'm going to add a couple more dents to it and call it quits. It' very lightweight and sounds very good.

As it is, it sound much better than the straight pipe. Much deeper. I'm going to add a few more ripples into it. It should be about right, as far as sound. I can always add a spark arrestor at the end.

[Joseph Farrow]

Back in the day we flared the end of our straight pipes so you could use the "stock" spark arrestor from the stock exhaust. Worked like a champ.

[350for350]

I like it. Pretty ingenious.

[ATC King]

Back in the day we flared the end of our straight pipes so you could use the "stock" spark arrestor from the stock exhaust. Worked like a champ.

That'd be nice, but I think the old bed railing, that's been out in the weather for years, will split if I try that.

Thanks for the idea. Good to see you posting too, it's been a while.


This pipe is just so I have something more than only the head pipe, terminating below the engine. The price of loud aftermarket pipes for these are nuts now and prices for blown out, used OEM ones are the same. This does run through the frame though and there was a stub of the old lower mount left, so I was able to weld that to it.

I put some more crimps in it and painted it today. I don't think it'll be any louder than a Cobra, which I used on my last one. Those things seemed to actually make it louder than a straight pipe.

The straight pipe sounds awful because it has that kind of sucking/hollow sound, almost like you can hear the exhaust valve opening/closing at idle. Small engines just sound terrible with straight pipes.

Once I get it back on, I'll post some pictures. The crimps are more of an experiment than anything, but they do make a difference. I haven't tried it with the additional ones yet, and I made them a little tighter. It's still going to be louder than I'd like. I may weld a washer with a smaller opening, into the end of it.

[kb0nly]

A lot of them that i have seen around here have a cheap little tractor muffler on them from the local farm supply store, i will give them credit, they actually sound really nice and not obnoxious. ATC exhaust parts are spendy for sure, aftermarket ones are a couple hundred at least, used are rotted out and still a hundred bucks. I put a DG on my ATC200 this month and it cost me $225.. That's a lot of money for just an exhaust header and resonator, but i have had really good luck with the DG thats been on my 200ES for the last ten years, its still holding up great. I think if i have to do it again on them though i will just buy the $20 muffler at the farm store and go with that and make some mounts.

Thats some cool old school fab work though, i remember seeing something similar on dirt bikes back in the 80's.. Pretty popular with the noisy bike crowd to tune them to their liking.

[ATC King]

I put it back on today, and it's still loud AF. I'll probably weld a washer on the end, or not, I've got other fish to fry.

Anyway, it's something useable and lets me get on to other things. I got to use some of the junk I had laying around, so that's a plus. Those bed rails have been around for at least a decade, so they finally got to be useful.

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I think this exhaust deserves the name, Colon Pow. It looks like a colon and is loud.

[jasong_10]

Love the name, lol. Looks cool too.

[kb0nly]

So you are saying she still farts pretty good eh?? Good name.. LOL

I think it looks cool regardless of how it sounds, thats old school fellers...

[ATC King]

I got to listening to this exhaust again and thought, hmm, it isn't really that loud.

So I set up a phone with a couple decibel apps on it and done the best I could to get some numbers. I didn't do a baseline on the completely straight pipe, which means this isn't very valuable, but still, I done it.

This was me try to keep the phone ~20" from the exhaust exit and at 45 degrees to it. I was expecting something more in the mid/high 90 range, but who knows how accurate these apps are or the phone.

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After riding my 185S that has a loud aftermarket pipe, the 110 didn't sound so loud anymore, which is what spurred this little test on.

[350for350]

That's amazing. I guess it's time to go ride then.

[MrConcdid]

I have considered taking a die grinder cutting into a pipe with a cut-off wheel say every 1 inch on opposite sides about half way through the pipe, then insert a washer into the slot you just cut and the weld it up, grind off the excess and you have just created a baffle alternating back and forth, then weld a washer on the end to reduce the size of the opening for added back pressure.
MrC.

[ATC King]

MrConcdid, if you ever get the time, I say go for it.

There's all different types of muffler designs out there and still more that probably haven't been tried.

On the backpressure deal though, it's not what it seems. Backpressure is a bad thing, what's needed is flow, meaning that too large of an exhaust causes a drop in exhaust gas velocity and in turn the system doesn't flow properly and causes a drop in power. The faster the exhaust pulses remain, the better cylinder scavenging. It's not the backpressure, it's keeping the exhaust gasses moving efficiently.

Also, exhaust tubing diameter doesn't function in a linear fashion. A 3.0" pipe doesn't have double the flow of a 1.5" one. Thinking of air like a fluid, and then think of a river. Rivers have channels in them, all the water isn't flowing at the same rate because of friction on the sides and bottom (depth matters too). Gasses in a pipe are similar. The gasses in the center of the pipe flow faster than those against the walls.

One way to keep exhaust gasses flowing is to keep the heat in the pipe, like by using header wrap. Loosing heat is loosing energy (velocity). Ceramic coatings vary, but some are better than others at keeping the heat in and moving out the tailpipe.

Not having a background in science specific to all of this (except some hydrology) , and no access to equipment for measuring performance parameters, I say go nuts and see if it works. All kinds of weird stuff happens sometimes, even when experts are involved. Certainly a guy in a home shop can make weird stuff happen.