[Kampnnut]

I just got my new ultra-glide classic EFI last week and 580 miles to date. What is the best way to modify the stock pipes? I can see the plugs near the back. I have heard to knock out both plugs on the left muffler and the back plug on the right one. Also put a hole in the front plug on the right side. I can understand why because of the volumetric efficiency of the engine. I can hear pent up power that just wants to get out.

One more thing, after the pipes are cleaned out, i want to put on a stage 1 air cleaner. Will chip need to be reprogramed?

Thank you for the help.

 

[HIPPO]

You will need a reflash if you use an air intake kit, if it is a 02 bike.

The stock pipes with the baffles punched out sound like $hit and often whistle. If you want to make noise there are real inexpensive slip on's on e-bay from the wild pig's guy. If you want to make more power use a two into one.

If money is a problem the Y pipe can be modified to make what amounts to a poor man's two into one, but you get what you pay for.

 

[HarleyJoel]

I agree with Hippo, alot of police bikes get the baffles knocked out and they sound like lawnmowers. Go the other route if you want to have a nice sound.

 

[Kampnnut]

Update

Just an update on how I modified my stock mufflers. On the left muffler, I knocked out both plugs. On the right muffler, I knocked out the back plug and drilled a half-inch hole in the front plug. This gives some exhaust restriction so more exhaust is routed to the left exahust. This should help balance out the back pressure. It sounds pretty good. I didn't want it to be too loud but still wanted to relieve some of the back pressure. I think this did the trick. The radio can still be heard nice and clear.

 

[JimmyK]

Re: Update

Just an update on how I modified my stock mufflers. On the left muffler, I knocked out both plugs. On the right muffler, I knocked out the back plug and drilled a half-inch hole in the front plug. This gives some exhaust restriction so more exhaust is routed to the left exahust. This should help balance out the back pressure. It sounds pretty good. I didn't want it to be too loud but still wanted to relieve some of the back pressure. I think this did the trick. The radio can still be heard nice and clear.

That sounds almost ( not quite ) the opposite of what a two into one would do. The 2 into one improves performance.

Hippos suggestion would be to compleatly restrict the left pipe. I could be wrong, but it seems that the way you rigged it, you be more inclined to lose power.

 

[alremc]

I just bought my father-in-laws 02 Ultra which he modified the mufflers by punching them out. He was told that the machine would require the Stage One installed to do that. He did it without the Stage One. He had no problems but they did sound pretty ugly. I have since re-installed the original mufflers. Anyone know if the computer needs anything?