Crystal Cranks

Looks like a combination of an old secondary muffler, cup by-pass and a track day has seen the demise of my secondary muffler. I have heard of reports of cup pipes putting more stress on them.

So what do I do now?, I could refit the primary and buy a G-Pipe, but I like the set up as it is, is there much of a difference.

Or does anyone that has a G-Pipe fitted have a secondary in ok condition that they do not need?

falcor

Is that the only crack? I'd cut out the cracked piece and weld in a new one. Should do as a temporary fix and then at least you can keep your eyes open for a spare muffler in the meantime.

PorscheZen

I've experienced the exact same situation. I was informed that the earlier year(s) ('89, '90, perhaps '91) Primary mufflers had weaknesses that caused this under higher pressure. I found a used primary at my mechanics' shop from a '92 then all was fine. Welding possible but I wouldn't trust it long term fix.

My experience with the famed G-pipe has been that I've removed it in the end, mainly due to the fact I didn't like the sound quality as much. (see this recent post)

velocitylover

I am on my 3rd secondary and yes I also have a cup pipe and de-cat.
The second muffler I blew was a brand new Dansk unit and it lasted about 1200 miles (gonna try to weld it this week).
When I am done with the 3rd the set up will have to change as it makes no sense long term....
It sure sounds awesome thou..

Crystal Cranks

If you look it's also gone all along the seam.



This does not sound good So maybe the G- pipe is the way to go.
It would be interesting to here other peoples experiences with this if you have gone through 3 maybe it is more common than I realised

That whole side is made from very thin material and looks like it could go a any point. If it was to be repaired the whole side would need to be cut out replaced with thicker sheet, would this be possible?
It might be the only way to deal with the pressure of the cup pipe.

gchristofi

my secondary looked very similar (when running cup pipe). A friendly welder fixed it and tacked down at the seam too and it's lasted the last couple of years....

hawk911

I have a secondary I'm not using. Close to Chicago, but it's not worth it to ship to Ireland

Crystal Cranks

Thanks for the offer Hawk, I've refitted the primary (not an easy one man job) and should have the G-pipe today, so I'll try this setup and if I find it OK I will probably keep it.

I might try to repair/ reinforce the old secondary or maybe somebody closer to me might have a good one.

falcor

Will be interesting to know what you think of the G-pipe. I have one on my car and it was mounted when I bought it, on idle it sounds ok but I think the slightly drony "put-put-put" noise on long trips a tad annoying. Sounds a bit like you're driving behind a HD motorcykle all the time.

Crystal Cranks

Got the G pipe on the other day, I like the sound off the cup pipe more, I think the cup pipe gives a deeper more refined 911 sound at idle but nice roar at high revs, the G Pipe is loud at idle but does not grow as well when the revs increase .

Falcor,I can see what you mean by this.

On the plus side there is definitely more low down torque making the car more drivable in traffic. ( I know some people say this dyno results don't show this, but there is definitely a change in how my car drives)

So do I get an new secondary so I can refit the cup pipe (and risk blowing another one) or keep the G Pipe ???