Normal vs. Divided Turbine Housings Discussion
#1
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There has been some discussion about the possible benefits of using divided turbine housings lately and I wanted to dedicate a thread to the topic for the ease of future searching. I have been reading about them lately and wanted to share a bit.
Please add your own sources of information on the subject as you encounter them.
![Name: SinlgevsTwin.jpg
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I knew the divided housings provided better spool, but didn't realize there was a penalty on the top end due to additional drag from increased surface area. I wonder if our little engines could push enough exhaust volume for the high end restriction to even be a problem?
![Name: TwinFlowHousing.jpg
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I also didn't realize the two inlets were introduced 180* out from each other inside the housing.
![Name: TurbineVolute.jpg
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Size: 48.4 KB](https://www.miataturbo.net/attachments/diy-turbo-discussion-14/189859d1501221501-normal-vs-divided-turbine-housings-discussion-turbinevolute.jpg)
This says that it helps to reduce cylinder to cylinder pulse interference. I was thinking that this would be more important on an engine that had six or more cylinders than one with just four, but that at higher RPMs it would easily be conceivable that the pulses from one and four would be heading straight toward each other in a log type manifold and meet somewhere in the middle. Obviously this would be less of a problem when using a tubular merging-type collector, and no one would use a log with a divided turbine housing.
Thoughts? Additions?
Please add your own sources of information on the subject as you encounter them.
![Name: SinlgevsTwin.jpg
Views: 2058
Size: 46.1 KB](https://www.miataturbo.net/attachments/diy-turbo-discussion-14/189857d1501221501-normal-vs-divided-turbine-housings-discussion-sinlgevstwin.jpg)
I knew the divided housings provided better spool, but didn't realize there was a penalty on the top end due to additional drag from increased surface area. I wonder if our little engines could push enough exhaust volume for the high end restriction to even be a problem?
![Name: TwinFlowHousing.jpg
Views: 2218
Size: 44.1 KB](https://www.miataturbo.net/attachments/diy-turbo-discussion-14/189858d1501221501-normal-vs-divided-turbine-housings-discussion-twinflowhousing.jpg)
I also didn't realize the two inlets were introduced 180* out from each other inside the housing.
![Name: TurbineVolute.jpg
Views: 3859
Size: 48.4 KB](https://www.miataturbo.net/attachments/diy-turbo-discussion-14/189859d1501221501-normal-vs-divided-turbine-housings-discussion-turbinevolute.jpg)
This says that it helps to reduce cylinder to cylinder pulse interference. I was thinking that this would be more important on an engine that had six or more cylinders than one with just four, but that at higher RPMs it would easily be conceivable that the pulses from one and four would be heading straight toward each other in a log type manifold and meet somewhere in the middle. Obviously this would be less of a problem when using a tubular merging-type collector, and no one would use a log with a divided turbine housing.
Thoughts? Additions?
#3
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If there's a penalty with high RPM use, but a significant gain in low RPM use, one could simply overcome the high RPM use penalty with a slightly larger turbocharger?
This might make the boost threshold/low RPM spool equal (no advantage for either) and at high rpm, the twin scroll would produce more power?
This might make the boost threshold/low RPM spool equal (no advantage for either) and at high rpm, the twin scroll would produce more power?
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*****.
I am buying a motherfucking new turbo with a .888 undivided housing. I am also going to buy a .91 divided housing. I will log them bitches so hard that that that I will have spool statistics and other things. The divided housing will be for a quick spool valve, assuming I can find one for something less that a ridiculous price.
I am buying a motherfucking new turbo with a .888 undivided housing. I am also going to buy a .91 divided housing. I will log them bitches so hard that that that I will have spool statistics and other things. The divided housing will be for a quick spool valve, assuming I can find one for something less that a ridiculous price.
#9
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*****.
I am buying a motherfucking new turbo with a .888 undivided housing. I am also going to buy a .91 divided housing. I will log them bitches so hard that that that I will have spool statistics and other things. The divided housing will be for a quick spool valve, assuming I can find one for something less that a ridiculous price.
I am buying a motherfucking new turbo with a .888 undivided housing. I am also going to buy a .91 divided housing. I will log them bitches so hard that that that I will have spool statistics and other things. The divided housing will be for a quick spool valve, assuming I can find one for something less that a ridiculous price.
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I did. The turbo is in the car right now. Sitting in the passenger's seat. Quick spool valve is on the way. It will spank the **** out of lag. .45 A/R for the spool win.
Moar details? What turbo? What car/engine?
#16
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If there's a penalty with high RPM use, but a significant gain in low RPM use, one could simply overcome the high RPM use penalty with a slightly larger turbocharger?
This might make the boost threshold/low RPM spool equal (no advantage for either) and at high rpm, the twin scroll would produce more power?
This might make the boost threshold/low RPM spool equal (no advantage for either) and at high rpm, the twin scroll would produce more power?
The first example in the OP assumes that one isn't simply using a larger twin scroll than the single scroll they would otherwise use, and assumes that the reader gives a flying **** about static, industrial applications.
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#17
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I guess il go **** myself since i have seen, in person more cars making bigger numbers with single scroll turbos? i said i was here to learn somehting new, stop being such a ******* ********.
for the record i hope it works fantastic, i would love to see miata with a nice twinscroll setup making good power. There is no reason i cannot b optimistic though.
for the record i hope it works fantastic, i would love to see miata with a nice twinscroll setup making good power. There is no reason i cannot b optimistic though.
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I guess il go **** myself since i have seen, in person more cars making bigger numbers with single scroll turbos? i said i was here to learn somehting new, stop being such a ******* ********.
for the record i hope it works fantastic, i would love to see miata with a nice twinscroll setup making good power. There is no reason i cannot b optimistic though.
for the record i hope it works fantastic, i would love to see miata with a nice twinscroll setup making good power. There is no reason i cannot b optimistic though.
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