Boost addicts 90 na, 2002 vvti engine, t04e twin scroll turbo, fully custom build
08-03-2016, 08:37 AM
#62
I was excited about this and was just going to watch, then it started going downhill.
Then I realized you're only going to use one wastegate, was really hoping for a proper twin scroll system but whatever.
Then on your last post I see you built the manifold completely wrong and you paired the incorrect cylinders, and that's where I stopped reading...
Then I realized you're only going to use one wastegate, was really hoping for a proper twin scroll system but whatever.
Then on your last post I see you built the manifold completely wrong and you paired the incorrect cylinders, and that's where I stopped reading...
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08-03-2016, 09:02 AM
#68
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Now I kind of want to see him finish this. I wonder how it will perform. Dont think it's been done this way before. Bets on if it's worse or equal to single scroll?
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08-03-2016, 09:04 AM
#69
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The only way to know would be to build the same exact manifold with a 4-1 merge and the same turbine A/R but in a single scroll on the same turbo, which won't happen. This turbo will spin, it will make boost: he will win because X.
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even more duh.
08-03-2016, 09:23 AM
#74
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The point of it is to separate exhaust pulses. So they don't run into each other/into other open exhaust valves. So you want 1&4 paired and 2&3 paired. Firing order is 1-3-4-2. So it fires into opposite scrolls each ignition event.
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08-03-2016, 10:02 AM
#77
I know nothing about manifold design... but I do remember something about 4-2-1 headers. Is there any substantial performance disadvantage to merging the 1&4, 2&3 BEFORE the turbo flange? Is the flow path too short at this point to make merging practical? I would imagine that it might make packaging easier. Am I mistaken?
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08-03-2016, 10:07 AM
#78
I know nothing about manifold design... but I do remember something about 4-2-1 headers. Is there any substantial performance disadvantage to merging the 1&4, 2&3 BEFORE the turbo flange? Is the flow path too short at this point to make merging practical? I would imagine that it might make packaging easier. Am I mistaken?
Yes you're mistaken. You have it backwards, there is a performance advantage when pairing 1/4 and 2/3 before the turbine housing, not a disadvantage. And yes it matters, it's the entire basis of how twin scroll works.
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