On a short but quick highway drive my 35 year old stainless muffler decided to break its welds and split open along the seam (along the length of the shell).
I’m seeking recommendations for a replacement muffler in an 1954 special equipment configuration xk120 OTS.
(1) 2-in and 2-out
(2) Inlet is a pair of square thick steel flanges that bolt up to mating flanges on the flex pipes.
(3) Outlet is typical expanded tubes for slip fit with tail pipes.
I see XK’s has a replacement system for $799. But I don’t wish to replace the down pipes, flex pipes or tail pipes (all stainless). So I prefer just a muffler.
In the UK we have exhaust fabricators who will make up what you need, sometimes while you wait and sometimes at very good prices (I’m think of Dean at Pipecraft in Basildon). There must be equivalents where you are, John?
I think those who live in the UK are spoilt by the avail of craftsmen and bespoke services for old cars.
I am calling some custom exhaust fabricators here in New England but so far their customization is mainly combining off the shelf silencers with bespoke pipes. I found a motorcycle shop that says they can fab a silencer in Stainless from scratch, but I suspect it’ll be quite expensive at $80/hour (60GBP/hour). It may help if I advise them I don’t care about cosmetics, just function .
One option might be to buy a pair of straight through stainless “glass packs,” and have them welded together and my old inlet flanges attached. These are cheap ($80 each).
I think you are right, our friends in the UK have access to sources and services that certainly folks like me in Canada simply do not (like having to send my damper to Oregon!). Although, there is (or was) a custom shop who will fabricate systems just up the road from me in Brantford. I used them when the “Double S” system I purchased did not line up with the hole in the chassis cross member to make me up a pipe to facilitate fitting. If you can find a shop with a pipe bender they will often make up systems.
I ran a pair of “Thrush” glass packs on my XK back in the day, produced a lovely rasp at higher revs. Interestingly, even though the system was mild steel, when I removed it to put on the ‘correct’ single muffler/pipe stainless system it was absolutely soild. The benefit of starting up and driving a minimum of 30-40 miles each time and drying out the innards. The raucous blast was replaced by a pleasant, muted drone and I suspect I might of lost a couple of horses as well! Good luck with your search.
Muffler was originally spot/pin welded. Spot welds broke (and there was spitting at some of the spot welds). There is about 1.5” of overlap in the shell. A friend welded the whole seam, and it is this continuous weld that has now broken. A possible kludge is to use a box of structural rivets (3/16”) in two rows down overlap. If I space them every 2” and stagger the two rows, that’s a lot of clamping strength. It could still vibrate loose, but it’s only $20 of rivets.
I have not heard of other SE mufflers break along their lengthwise seam. I think this particular muffler I have is simply built design/poorly.
Nice to hear someone actually tried thrush glasspacks on their Jag. Hard to imagine it would be louder than the original SE exhaust.
Several with 2.5” inlet/outlet look like they are the right size. The tubes would need to be reduced to 2” to match the flanges and rear pipes. Thrush sells a stainless glasspack with 2” inlet/outlet, small diameter body and short enough. I think a pair of these will require less work to fabrication.
Welding failure. Brittle fracture along the heat affected zone. It was welded too hot. Carbide precipitation in the hotter than necessary weld zone changed the crystalline microstructure, leaving it embrittled. The base metal expanded greatly when it was heated, then contracted when it cooled. The residual stress in the heat affected zone combined with the brittle condition allowed the crack to form.
Mabe Bill Bassett? I have his muffler and am quite happy.
If, however you would like to buy his entire exhaust system, ask him not to weld the square collars - I think it’s best to do it after fitting on the car.
