Hey all
I have a complete W code 1.7 out of a 411 wagon and the muffler is very close in appearance to the Type 3 muffler with the tip poking out the center of the muffler at an angle.
This past weekend I took parts off the 412 wagon mentioned in the "junkyard alert" thread and it also had a 1.7, I just can't remember the engine code but the heads are "Q"s. The muffler was shaped more like the 914 muffler, sort of banana round shaped and the tip was poking out the end on the passenger side. I decided the muffler on this one was too far gone with rust so I left it behind.
Any performance differences between the two?
1.7 muffler differences
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Class 11 streeter
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1.7 muffler differences
So you think your project is taking forever eh? Well you've got nothing on me.....
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raygreenwood
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- Joined: Wed Jan 22, 2003 12:01 am
Yes, I have had numerous rants on these mufflers. The center pipe style is actually the quietest and appears to be the most restrictive. The end pipe design, seemed to vary the most and they varied by brand. The brands you see are VW stamped....several compaies built those, Lange...a decent aftermarket company, Leistritz...another decent aftermarket version, Starla and Dansk....two aftermarket companies that make OK mufflers...but the most restrictive due to sloppy welding. Ernst...who makes a really good one that flows about as well as the basic bus header you see floating around.
I am working on a design right now....(hope to build it for mine in the fall)....that is very similar to the factory stock in size and shape, but better flowing.
The factory unit is not a horrible design. Its just that its volume is best suited for 1.7/1.8 max. Also, the center pipe design on the inside is usually the restrictor. On some models the baffel holes are just too small. Iwill have to post a diagram of the way the inside of these flow. It rather ingenious. With a couple of changes, it could be made into a 4-2-1, with only moderatly larger bulges in a couple areas. Rigt now...it is a 2 into 2...each heads header pipes are paired...so its not tuned. Each heads header....flows a certain length in their respcetive pipe..then they dump into the main can...where they flow into and around the end of the central pipe. So in cross section it looks like a stack of 3 pipes inside.
By spliting the cylinder header pipes off...into tuned pairs, you will add two bulges by pairing up 1 and 3 and 2 and 4. Their collectors woul meet across from each other on either side of the center pipe. The center pipe would be enclosed in a slightly larger center pipe, where the twwo header "y" connect with an up-turn. Thats the "2" section. The center pipe would have perforations running all the way up the length. It would have a flared tube welded inside of that to separate what flows through the perfs, from the excess that flows around the end. If the length of the inside pipe is correct, the gasses that go through the perfs should "suck" the end around gases through. It will be a 4 pipe cross section, not a 3-pipe. I think I couldmake it the same length but slightly larger in diameter than the stock Ernst. Ray
I am working on a design right now....(hope to build it for mine in the fall)....that is very similar to the factory stock in size and shape, but better flowing.
The factory unit is not a horrible design. Its just that its volume is best suited for 1.7/1.8 max. Also, the center pipe design on the inside is usually the restrictor. On some models the baffel holes are just too small. Iwill have to post a diagram of the way the inside of these flow. It rather ingenious. With a couple of changes, it could be made into a 4-2-1, with only moderatly larger bulges in a couple areas. Rigt now...it is a 2 into 2...each heads header pipes are paired...so its not tuned. Each heads header....flows a certain length in their respcetive pipe..then they dump into the main can...where they flow into and around the end of the central pipe. So in cross section it looks like a stack of 3 pipes inside.
By spliting the cylinder header pipes off...into tuned pairs, you will add two bulges by pairing up 1 and 3 and 2 and 4. Their collectors woul meet across from each other on either side of the center pipe. The center pipe would be enclosed in a slightly larger center pipe, where the twwo header "y" connect with an up-turn. Thats the "2" section. The center pipe would have perforations running all the way up the length. It would have a flared tube welded inside of that to separate what flows through the perfs, from the excess that flows around the end. If the length of the inside pipe is correct, the gasses that go through the perfs should "suck" the end around gases through. It will be a 4 pipe cross section, not a 3-pipe. I think I couldmake it the same length but slightly larger in diameter than the stock Ernst. Ray
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Class 11 streeter
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- Joined: Sun Nov 11, 2001 12:01 am
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raygreenwood
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