Dansk Mufflers are Crap and this is Why

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C J Murray
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Dansk Mufflers are Crap and this is Why

#1 Post by C J Murray » Fri Dec 06, 2013 11:11 am

I've complained about this before, along with others here. Every time I buy one of these I have to fix it or I end up with multiple leaks and backfires.Every one is junk. The company refuses to respond to emails on the subject. Our suppliers, who may have some pull with Dansk, do not comment. If MK would show me what is inside their stainless muffler I would buy them instead, if they fit better.

First, the Dansk cylinder 1 and 3 pipes have too big an ID and are too short to seal over the factory J-pipes. If not addressed, all Dansk mufflers leak at both slip joints.

Then comes the not so obvious problem...the flanges for cylinder 2 and 4 are never in correct alignment. When out of alignment, there is only part of the gaskets that are pinched with pressure between the head and the muffler flange. The portion of the gasket that is not pinched quickly blows out and this is the source of the really loud backfires because the leaks are so close to the flame source. Tightening the nuts excessively will not create enough force to move the flanges into correct alignment. This has to be corrected by measurement, grinding, and filing. It is ridiculous to pay that much for such a poorly made item produced by a company that could easily fix this but simply does not care. It would also be nice if somebody made a gasket that was more substantial than the ones commonly available but the real problem lies with Dansk.

Here are some pics of the problem...

the aluminum block accounts for the cylinder head offset and the straight edge should lay flat, but does not
IMG_0267.jpg
level the muffler body...
IMG_0260.jpg
the right side is not even close to correct
IMG_0261.jpg
left side is better but leaning the opposite direction which adds to the problem
IMG_0262.jpg
note the considerable wedge shaped gap at the left-my level is behind the straight edge in this pic which hides the severity of the problem unless you look closely
IMG_0266.jpg
You must also check alignment or level 90* from what my pics show.

While we are at it...their paint is also crap.

I hope this post gets back to Dansk or that our suppliers forwards it to them.
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Matthew Devereux
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Re: Dansk Mufflers are Crap and this is Why

#2 Post by Matthew Devereux » Fri Dec 06, 2013 11:39 am

Crap. I just ordered one. How new is the muffler you inspected?
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Phil Planck
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Re: Dansk Mufflers are Crap and this is Why

#3 Post by Phil Planck » Fri Dec 06, 2013 11:41 am

Cliff (& others)

Here is email address for Leistritz:

produktionstechnik@leistritz.de

Maybe if enough of us inquire/urge they could make a run, or at least supply blueprints.
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Re: Dansk Mufflers are Crap and this is Why

#4 Post by Mike Smith » Fri Dec 06, 2013 12:00 pm

The so called Sports Mufflers (used usually on `A`s) also have a problem, in that the construction internally is different to the original ones

When you `bottom-out` The Tips on a road dip (as you will at some point) the stress is put onto the outer case weld and not onto the pipes inside the main box.

I do not have time to make drawings and explain but I cut open both Original and Dansk to find out what was going on - it is a Design and Construction problem

I made a fuss about this with Dansk and was told that the complaint had to be made and the unit returned - through my supplier
As my supplier for that unit was in Germany - this meant back to Germany and then on to Denmark -- I did not bother and just stopped supplying these units

Dansk have the same poor quality of Design and Construction in relation to J` Tubes and Heater Valves which is why we went ahead in the UK and remade the complete range of Heater Control Valves.
We just tore an Original apart and copied it piece by piece down to the number of spot welds.

We need to do the same with all the Muffler Box`s but it is a cash flow issue
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Re: Dansk Mufflers are Crap and this is Why

#5 Post by jim nelson » Fri Dec 06, 2013 12:39 pm

The Euro mufflers from Dansk are no better, lots of fitting involved.

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Re: Dansk Mufflers are Crap and this is Why

#6 Post by Matthew Devereux » Fri Dec 06, 2013 12:49 pm

I just bought one on sale for $350 so I don't mind doing some fitting. They really need some proper jigs and welding procedures.
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Re: Dansk Mufflers are Crap and this is Why

#7 Post by Jacques Lefriant » Fri Dec 06, 2013 1:20 pm

Hi CJ
Please put your findings in a polite form and email it to me i will forward it to my contact at Dansk USA and to their bigger distributors. Have you tried using multible gaskets?
j
 

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Re: Dansk Mufflers are Crap and this is Why

#8 Post by C J Murray » Fri Dec 06, 2013 2:47 pm

The muffler pictured is an A muffler that was new late last year. The backfires started almost immediately.
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Re: Dansk Mufflers are Crap and this is Why

#9 Post by Vic Skirmants » Fri Dec 06, 2013 2:48 pm

Multiple gaskets are a bad idea. You're still not clamping evenly.

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Re: Dansk Mufflers are Crap and this is Why

#10 Post by Peter Silten » Fri Dec 06, 2013 3:14 pm

Here are a related series of posts:

http://porsche356registry.org/356talk/1/33244.html

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Re: Dansk Mufflers are Crap and this is Why

#11 Post by C J Murray » Fri Dec 06, 2013 3:33 pm

A couple of weeks ago I made the same repair to a Dansk sport muffler on my friend's Cab that has been blowing gaskets for 10 years! I had to repair every Dansk muffler that I ever bought. The stainless faux Abarth that I got from NLA some years back needed no repair. Just take it out of the box and bolt it up, easy peasy. How is it that a small run of mufflers is correct and the volume producer has zero quality control?

Jacques, I looked for the email that I sent them many months back but I must have deleted it. Please just send your contact the link to this thread. You are only trying to help him so he should not be upset. My email was very respectful(really!) and they didn't bother to even reply. With all of the negative feedback that has been posted here for years and the fact that long time pros world wide like Mike Smith have no effect on Dansk and their quality problems then I think there is no hope. The only hope would be if major 356 parts houses withheld orders until the product is improved. The problem is that they would all have to do so at the same time. Not likely.

Does anybody know the owners of MK and can convince them to show us what is inside their mufflers? The Porsche designed muffler was quite good for performance and was quite complex. I think that having the 2/4 pipes extend inside the muffler for equal length to the 1/3 pipes is important. I think Dansk follows the Porsche design, maybe, but nobody else does, I think, don't really know. I would love to know.
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Re: Dansk Mufflers are Crap and this is Why

#12 Post by Jacques Lefriant » Fri Dec 06, 2013 3:45 pm

Hi CJ
Bob Diotte i beleive is running Dansk USA and has been in the industry forever i will forward this post to him.
Hi Vic i recall some of the euro exhaust having longer exh studs and spacers/ extra gaskets to make the pipes come out right i would only use extra gaskets if it would help correct an offset problem and assist in even clamping.
 

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Re: Dansk Mufflers are Crap and this is Why

#13 Post by C J Murray » Fri Dec 06, 2013 3:55 pm

Very many years ago I worked for Dana Corp/Victor Gaskets. We sold many different types of exhaust manifold gaskets constructed of many different materials. This is how the engineers fixed certain problems that cropped up on some applications. One size does not fit all. The mesh core material with no fire ring facing the exhaust gas is the cheapest crap you can use. I don't know what Porsche used for material and design back in the day but what we are using now requires everything to be perfect to work.
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Re: Dansk Mufflers are Crap and this is Why

#14 Post by Olivier AUVRAY » Fri Dec 06, 2013 4:18 pm

If you're looking for good quality parts, there is something new in Europe: Eisenmann (from Germany) offers mufflers for 356. On the following link you can see some pics:

http://www.eisenmannshop.nl/

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Re: Dansk Mufflers are Crap and this is Why

#15 Post by jim nelson » Fri Dec 06, 2013 5:45 pm

Jacques Lefriant wrote:Hi CJ
Bob Diotte i beleive is running Dansk USA and has been in the industry forever i will forward this post to him.
Hi Vic i recall some of the euro exhaust having longer exh studs and spacers/ extra gaskets to make the pipes come out right i would only use extra gaskets if it would help correct an offset problem and assist in even clamping.

Euro exhausts aren't dependent on studs or gaskets, they are fitted to the ultra-expensive (if you buy 'em new) Euro heat exchangers, so two pipes per side…
photo copy 2.JPG
(Now why did this come out sideways???)

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