TantrumWerks New Year sale on LaBree Motorsports Split Downpipes
01-18-2005, 08:03 AM
#21
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Here's some betime reading material...
This was written by an engineer at Garrett turbos...
Just like the Matrix...you've got to make up your own damn mind...
<a href="http://www.tantrumwerks.com/html/Split%20DP%20support%20theory.pdf">Divorced Wastegate theory</a>
But I wouldn't knock these until you try them...
Just like the Matrix...you've got to make up your own damn mind...
<a href="http://www.tantrumwerks.com/html/Split%20DP%20support%20theory.pdf">Divorced Wastegate theory</a>
But I wouldn't knock these until you try them...
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01-18-2005, 08:05 AM
#22
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that is totally different though ..the wastegate isNOT part of the turbo housing
2 different things, and 2 different pipes.. smooth transitions turbo-dp and wg-dp .
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01-18-2005, 08:16 AM
#26
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I've read the theory and I totally agree.
My concern is with the execution. The physical constraints of the S4 engine bay don't allow for a very large primary tube. I'd worry that it would present a flow restriction.
From the very article you linked to: "For 450-500 hp, even 3" is on the small side."
Granted that is referring to a single exhaust, but it still calls into question the effectivness of a small primary tube. If the engine bay would allow for a 2.5-3" primary tube and a smaller wastegate tube, I'd be all for the split design.
-Dave Pramanik
From the very article you linked to: "For 450-500 hp, even 3" is on the small side."
Granted that is referring to a single exhaust, but it still calls into question the effectivness of a small primary tube. If the engine bay would allow for a 2.5-3" primary tube and a smaller wastegate tube, I'd be all for the split design.
-Dave Pramanik
01-18-2005, 08:39 AM
#28
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I thought Simpply dynoed the Split 2's, those pipes are larger, there
was not a major power difference compared with the orginal splits.
Maybe Simpply can chime in with the differences in tubing diameter etc.
Maybe Simpply can chime in with the differences in tubing diameter etc.
01-18-2005, 09:02 AM
#29
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You still have another contraint...exhaust side of the turbo
If we have a turbo system where the wastgates weren't incorporated in to the exhaust side of the turbo, we could run something like the pics Mark put up or something like the old URS4 DP (remote wastgate).
I've stated before, the DP is not the restriction, the turbo housing is. I'm looking for some really old pics that illustrate this. The primary tube for the turbine is large enough on K03 & K04 housings that the turbo housing should be machined, not the DP.
I've stated before, the DP is not the restriction, the turbo housing is. I'm looking for some really old pics that illustrate this. The primary tube for the turbine is large enough on K03 & K04 housings that the turbo housing should be machined, not the DP.
01-18-2005, 09:28 AM
#30
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More from that article: "Again, less pressure downstream of the turbine is goodness."
Just having a downpipe the same diameter as the turbine housing inlet/outlet doesn't really make the turbine the restriction.
You want less back pressure to allow the tubine to spin more easily.
-Dave Pramanik
You want less back pressure to allow the tubine to spin more easily.
-Dave Pramanik