Muffler repack = Retune?

[T Evans]

I have a set of Jardines that I am going to repack because they have gotten louder and louder. Turbofan posted a good article on this subject.
My question is, once you install the new packing, is this going to change your back pressure enough that it would require a retune to compensate from this?
I noticed in his article that they wrapped SS wire around the fiberglass on the new baffle which held the fiberglass on the baffle. If you greatly increased the amount of wire used by decreasing the distance of the wraps, I would think that would allow for more support of the fiberglass thus decreasing the amount of air that would be able to get thru the fiberglass. And to me this would also extend the life of the new fiberglass and instead of needing to repack them every 12k to 15k miles, you might be able to strech this out to maybe 20k
But by reducing the air flow out of the muffler, you increase the back pressure and the question is. Will it reduce the air flow enogh to require a change in the A/F mixture?
Anybody with expirence or thoughts on this?

Big T

 

[STRIPES]

I REMOVED the fiberglass from my Jardines and added a few more holes in the baffles Idles quietly but not quiet at all with any load on the motor.

 

[RatBoy]

But by reducing the air flow out of the muffler, you increase the back pressure and the question is. Will it reduce the air flow enogh to require a change in the A/F mixture?
Anybody with expirence or thoughts on this?

Big T

First a question.. Are you running a PC3?

I ask because the PC3 usually is used with an O2 sensor bypass, or if you a tuneboy.. the O2 sensor turned off. The O2 bypass 'tricks' the ECU by sending a constant voltage so that the ECU doesn't 'learn'... i.e. the ECU won't adjust to the new backpressure.

I'd try the '12-Minute' tune first, retune second if you aren't happy with the results.

Second... an observation..
I was watching a bike building show and they were making their own cans. They drilled the baffle, wrapped the baffle in steel wool and then the fiberglass packing. I've never done it myself so I can't give you first hand experience, just an observation.

 

[TriumPhil]

RatBoy, you musta' missed all the drama T had when he installed his now, thankfully, functioning TB.

What channel is that bile building show on... I'm due for a good cleansing!

 

[T Evans]

Yes on the PC3 and yes on the TuneBoy. I think that with a T/B you can go in and click a icon in the program and this resets everything without having to do the 12 min. tune. I think thats what Pigr9, Brian had said.
Stripes was nice enough to sell me his TuneBoy. Thanks again Ken.

As for the steel wool, sounds like a good idea. The steel wool would see the heat and the pressure first and might extend the life of the packing. Might be worth a try. That may extend the life of the packing but I don't guess there would be any way of telling if the new packing was effecting your A/F without being able to see what it was prior to re packing the mufflers and then check it after you've installed the new packing.

T

 

[dougl]

Any time you reduce or increase the amount of air going through, you should have to adjust the fuel. I believe the 12 minute tune just does a reset adapt, which undoes any learning the ECU did. This won't adjust the main fuel tables. The original jardines were louder and probably less restrictive than the later model. PCIII and tuneboy have Jardine tunes, but the PCIII one assumes you have the stock Triumph tune loaded and are using the same jardines they used. The Tuneboy jardine tune needs to have the same jardines as you do. In any case, none of the stock triumph tunes should be ideal for jardines. The best thing to do is load the best tune you can (stock triumph, PCIII, or tuneboy) and have it dyno tested (<$50) and see how the power curves and A/F curve look.

 

[Pig9r]

I think the pipes are pretty much straight through anyway. I wouldn't think that should be enough to worry about.

 

[HellFire]

Have you ever seen steel wool burn? I don't think I want that in my exhaust.

 

[xhdskip]

If you're worried about the A/F ratio,
you can do what I'm gonna do and get a
TFI controller.

 

[T Evans]

TFI controller????