This is about plain old garage hotrodding and saving a few bucks. Harleys cost enough without having to throw cubic money at them to pay the epa tax.

I was going to buy some slipons but $200 plus just didn't set well with me. So today I took them a friend's shop and we went to work.

We first started with a dremel and cutoff wheels to attack the welds at the outlet ends of the stock mufflers. This was working but was slow so he found the correct size holesaw and put it in the 1/2 in drill.

That weld is hard and I was hand holding the muffler vertical while he ran the drill. A drill press with the table lowered way down would have been better.

After getting through the weld it is necessary to knock the baffle in [towards the front] a bit and then grind the excess weld with a dremel.

When this is smooth you can knock the complete baffle out the back end.

You will see that the baffle is a somewhat conventional baffle covered by an almost totally perforated tube. This tube has hundreds of very small holes and lets the gas access the packing that is next to the outside wall of the muffler while keeping the packing away from the actual baffle.

This outer tube isn't necessary and is welded in two or three places to the back end of the normal baffle. Take this assembly to a bench grinder and grind these welds off and knock the outer tube off the inner baffle.

[Note: This outer tube would make a very fine hi flow baffle with the addition of a solid disc welded in it at the same location as the disc in the original smaller baffle. You would have to get the packing out of the shell for this to work though.]

You now have the actual baffle in your grimy hands and the modding can start. I recommend leaving the central blocking disc alone. I have read it is necessary for a properly timedreflected wave and also it is said to stop reversion. If you knock it out I believe you have a muffled straight pipe...

The inlet side [ahead of the central disc] has many holes approx 3/16 in and I added three - 5/16 inholes in addition.

The outlet side has far fewer holes [also approx 3/16] and I added ten - 5/16 in holes.

The number and size are just a guess on my part.

You are now ready to reassemble. Remembering the outer baffle cover, cut a piece of it approx 3/8 to 1/2 in long to use as spacer to get a correct fit at the outlet end.

You now have a choice of drilling a hole through the shell and baffle and using a smallscrew and nut, or a small weld.

My buddy is a superb welder and we chose to weld the baffle assembly back in. Of course this discolors the chrome so we did it on the bottom and back side. Just two very small welds.

This write up may makethe jobsound worse than it really is. It took us about 2 and 3/4 hours and we didn't know what we going to find when digging into it. If you have a helper and access to a decent shop it is not that big of a deal. Take your time and don't force things.

Results are surprising. I expected a large increase in noisebut there is none at all. The tone is somewhat lower but it is very quiet. I'm sure this would be vastly different if we had removed the packing though. I can't even hear them over the ness big sucker.

I don't think I hurt the low end torque any and it seems to pull harder from 70 to 90 mph now. Of course this is subjective and my butt dyno isn't calibrated.

The ness big sucker and baffle mods are all I have done to the 08 super glide. I know it is lean and several full throttle rollons in third and fourth gear seem to indicate better acceleration when rolling the throttle back a tiny bit. This means lean.

I plan on a revtech or similair dfo soon.

 

Hi-
Maybe try Thunder Monster baffles....? http://www.bigcitythunder.com/pages/product-fit.html

 

Thanks. They look okay but I wanted to work with what I had.