dual zork??

[mark houghton]

Saw this on.....eBay, of course. No affiliation with the seller. Never seen anything like this. Seller calls it a racing exhaust. Appears to be a twin zork.

[JFairman]

Those are Supertrapp stack on diffusers on the ends of the pipes or an asian copy of them.
You can add or subtract diffuser discs that are held in place with allen head bolts and change the amount of sound level and backpressure with them. They are a type of tunable muffler.

They are usually used on the ends of supertrap straight through aluminum and stainless glass pack mufflers and were popular on motorcycles in the eightee's and some race cars.

For whatever reasons they are not as popular these days as they were 20 years ago.

[mark houghton]

Thanks for the explanation. Didn't look like something I would want to put on my turbo. The diffuser discs look like what I have on my old 70's dirt bikes expansion chamber silencers...help to tune the shock waves.

[RarlyL8]

Good lord that is awful. The end caps would kill power. Cannot imagine what it would sound like or look like on the car.

[JFairman]

I wouldn't want that on my car either but you can add or stack on as many diffuser discs as the bolt lengths can hold. The backpressure drops, torque rpm curve raises, and sound gets louder the more you add on.

Remove diffuser discs and the exhaust gets quieter with a little ffff ffff sound added into the exhaust pulses at idle and the torque rpm curve lowers.
So in that way the supertrap diffuser tips are a good design and the only quick and easily tunable sound exhausts ever made.

I have a CC products exhaust system with dual supertrap mufflers on a BMW R90S motorcycle and I've experimented with the amount of diffuser discs so I have some experiece with them

Take all the diffuser discs off and it's just a straight pipe off the turbo like a "zork"

BTW, where did the word "zork" for a straight curved pipe off the turbo come from?
I never heard that term anywhere before reading these forums.

[mark houghton]

Originally Posted by JFairman

BTW, where did the word "zork" for a straight curved pipe off the turbo come from?
I never heard that term anywhere before reading these forums.

Have always wondered that myself. I would be more comfortable if there was a German translation for zork (der zorkenheimer, maybe)?

[JFairman]

zorkunschnabble

[RarlyL8]

I've used supertraps as well, on my 73T with Webers and on motorcycles. Would never put one on a 930. The design is anti-turbo in terms of flow. You would have to add so many discs that it would defeat the purpose.

[JFairman]

Back around '86 IMSA had a sound level rule for the GTPrototypes and the winning V6 twin turbo Silk Cut Jaguars had to have mufflers to race here in the USA.
They chose to use twin stainless steel Supertraps with about 3" of stacked diffusers because they worked.. and you could quickly change the sound level of the exhaust for different tracks.

When they raced outside of the USA they just removed the diffusers and then they become straight through glasspacks with no more backpressure than a straight pipe.
I don't have a pic of the car with the diffusers on the Supertraps but I remember seeing them on the car when it raced at Sebring.



Kevin Jeanette of Gunnar Porsche also chose supertraps for the RATT when he restored it. This car is for sale on his website.

[sprbxr]

I used to work for a team that ran e30 M3s in Firehawk back in the 80s. At Lime Rock we were over the dB limit so we took a pair of kevlar gloves we used for brake changes during pits stops, cut the ends of the fingers and thumbs off the gloves and hose clamped them to the end of the twin exhaust pipes. We were just under the dB limit. it looked ridiculous as the car went by, like someone was waving from the back of the car. Hilarious.

[pkracer21j]

Originally Posted by sprbxr

I used to work for a team that ran e30 M3s in Firehawk back in the 80s. At Lime Rock we were over the dB limit so we took a pair of kevlar gloves we used for brake changes during pits stops, cut the ends of the fingers and thumbs off the gloves and hose clamped them to the end of the twin exhaust pipes. We were just under the dB limit. it looked ridiculous as the car went by, like someone was waving from the back of the car. Hilarious.

The things racers do in a pinch...I like it! reminds me when I was racing in the rain and we had a new intake setup that made a few more hp in the dry...sucked in water in the rain though, we took gallon milk jugs and cut off the bottoms, and widened the lids to shroud the filters from water. it worked, we won, and looked completely rediculous. I still have those milk jugs. haha

[Jim2]

Years ago we flowbenched a supertrap, the results were dismal. A $50 off-the-shelf chambered performance muffler flowed better. I think the supertrap had about 1.5" of plates stacked up. Both units had same size inlets.

Don't see them much anymore unless it's a preserved antique racer.

Edit: Gloves... Milk jugs... classic!

[krasuskyp]

Originally Posted by JFairman

Kevin Jeanette of Gunnar Porsche also chose supertraps for the RATT when he restored it. This car is for sale on his website.

my GAWD I can nearly hear that car ripping a hole in the atmosphere just sitting here from behind me monitor - NOICE!

sprbxr / Petey... literally LMAO:



bwaHA! awesome

JF / Mark... ^ditto^! Tx for posing the Zork Q I was too shamed not to know/ask - I always thought (and hoped not) it was supposed to be something like how those stoopid Snorks had them top snouts on their heads, or someting. Zorkenheimer / Zorkenschnabble - hhahahaaa classic...

[Craig 930 RS]

[A930Rocket]

The Supertrap had to be the worlds worst muffler or what ever you call it. Add it to an RX7 and the noise was deadly.

[cl8ton]

A muffled Zork...where's the fun in that?