Stock exhaust mod?

J

junked

New Member
I have my stock muffler gutted. I removed the cat and baffles. I was wondering what if anything I should do about the length. I tried it out and it has less bottom end torque than it had prior to gutting it. I can weld, so adding to it won't be a problem. I could buy an expansion chamber but, would rather try to make this work better. Any suggestions would be appreciated.

Thanks
 
So what you have done is made a crude expansion chamber. Should probably work better than it was so now you are at the tuning stage. You say you lost some bottom end well then lengthen the header section. Longer is more bottom end and shorter gets you more top end. Hope that helps.
 
Sounds good, that will give me a chance to relocate it.

A can of Glade air freshener fits perfectly snug around the muffler. I can lengthen and shorten at will. Might make a good tuning tool.
 
Last edited:
How long or short are you going to make your muffler? I just had the innards blow out of my muffler so I have nothing but a shell with a plate on the bottom. I f I can mod this to my benefit, It would help. Glade aerosol can huh? Thanks for that info. I'll be watching this thread to see how it goes. Thanks.
 
Like GhostO saids:
If you want to gain more bottom end, then you will want to legthen the header pipe(that would be the pipe that comes from the engine,you would need to cut it and add a piece of pipe or hose)not add one on the end of the muffler. let us know how it goes.
 
What exactly is "bottom end"? Do you mean I would gain more speed at WOT? Or would I climb hills faster?

The whole thing on exhaust confuses me. My diagram may give some insight as to what I want to know.
I essentially would like to know the best case scenario and what the outcome of each would be?

I guess I figure with my muffler gutting itself now is a good time to experiment. But as this is my only way around I can't afford a flop.

What type of hose could I use on the exhaust w/out it burning?

Thanks in advance
 

Attachments

  • Exhaust.jpg
    Exhaust.jpg
    33.4 KB · Views: 1,727
  • Exhaust II.jpg
    Exhaust II.jpg
    34.9 KB · Views: 1,306
To be a true tune pipe i believe the sound waves must be concentrated after the exhaust port open's to the point of origin at just the right time. Your design seems to be possible I was just wondering if you were planning on beveling the sides like your last diagram I think the flat bottom of the glade canister would cause sonic confusion inside the chamber resulting in power loss. But I could also be wrong and you may of stumbled into a total pro trick.
 
I was curious about the design. The beveled ends were an after thought based on what I have seen in the design of Expansion Chambers, and how they all taper at each end. I was suspicious this wasn't just for aesthetic purposes. Is there a way to figure the size an expansion chamber needs to be? Does it have to be bent? Or can I manufacture one in the process of repairing my muffler? How would one go about tuning a pipe? Is it a mathematical thing or is it just trial and error? Could I make a poo poo pipe or does that affect my motor as well?
 
Marcosis said:
To be a true tune pipe i believe the sound waves must be concentrated after the exhaust port open's to the point of origin at just the right time. Your design seems to be possible I was just wondering if you were planning on beveling the sides like your last diagram I think the flat bottom of the glade canister would cause sonic confusion inside the chamber resulting in power loss. But I could also be wrong and you may of stumbled into a total pro trick.
Click to expand...

I used the Glade can before with ok results, but now that the muffler is gutted I am going to try it again
I will first lengthen the header and then try tuning with the Glade can. I know it sounds wacky, but the can fits perfect and the top end of the can has a cone shape. It's a good way to learn if nothing else.

The length of the expansion chamber can be changed from 0 to about 6 inches just by sliding the can on the muffler. Doing so affects the timing of the exhaust pulse so it should give me some ability to tune.
 
Last edited:
Here is the finished product. It sounds great, and adjusting length has a big effect on powerband. Still testing. dnut
 

Attachments

  • DSCF0003-1.JPG
    DSCF0003-1.JPG
    271.3 KB · Views: 1,426
  • DSCF0005.JPG
    DSCF0005.JPG
    428.5 KB · Views: 1,547
  • DSCF0005-1.JPG
    DSCF0005-1.JPG
    488 KB · Views: 2,434
  • DSCF0007.JPG
    DSCF0007.JPG
    436.2 KB · Views: 1,298
I just gutted my stock exhaust, pulled the cat and drilled out a 1/2" hole at the end. I am stoked on the performance but its kinda loud. Can I stuff anything inside to silence it a bit or should I try something else? Any advise is appreciated.
 
Yes, fiberglass insulation but, it tends to get oiled up depending on how your engine is running. I will post a video of the "Glade can Mod" it sounds real nice.
 
what about diong the glade can but keeping the muffler gut in place? and how do you get the guts out without destroying them?
 
You must log in or register to reply here.
Back
Top