Twin Scroll Turbos?? Monster Spool.. FACT or FICTION???
No one swapped a TS turbine on a non TS manifold. Its ridiculous you would say or insinuate that.
If you read my post, I never said it doesnt work. I said when driving the car on the street, its much more responsive and recovers from shifts or throttle let off much better. So please stop acting like I said it doesnt work. I just said I didn't see the "Monster spool" everyone talks about.
And if its so easy to show the monster spool difference, why in this 28 page thread, there is barely any quality data??? There is only two people that posted data of same car, same setup, and just manifold/hotside changes. One showed a big difference in spool, one didnt. If you have dyno charts, why dont you post them?? Do you have a baseline dyno of a T3 SS .63 housing, then dynos of a TS T4 1.06 housing showing the difference, on the same car, same setup? If so, please post.
If you read my post, I never said it doesnt work. I said when driving the car on the street, its much more responsive and recovers from shifts or throttle let off much better. So please stop acting like I said it doesnt work. I just said I didn't see the "Monster spool" everyone talks about.
And if its so easy to show the monster spool difference, why in this 28 page thread, there is barely any quality data??? There is only two people that posted data of same car, same setup, and just manifold/hotside changes. One showed a big difference in spool, one didnt. If you have dyno charts, why dont you post them?? Do you have a baseline dyno of a T3 SS .63 housing, then dynos of a TS T4 1.06 housing showing the difference, on the same car, same setup? If so, please post.
no one has? are you blind? a simple search show's some who have done that. even some shops have. its sad. it is even in this thread a ways back i think. i could be wrong there as i have read many TS/OS threads so do not hold me to it. i did not say that is what you are doing either. it is what ''people'' are doing. i was not even pointing the finger at you with my original comment. it was in general. i have experience with 1 open scroll VS TS on my own car. then i have experience with a GT30R T3 .78, and 1.06. GT35R T3 1.06, and T4 1.06 HTA86 T4 1.06 and PTE 6466 T4 1.15. also T3 small runner and T4 small runner. now i have T4 big runner and may try the PTE 1.32 my PTE spools just as fast as my HTA did with a bigger turbine and STM650 cams. the HTA had BR-BF272. my dyno charts show my setup spools up quicker then most guys reg or HTA 35R open scroll turbos and mid/top can hang with them as well. my driving on the other hand can not.
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). A divided housing is a necessity to be a twin-scroll, not a sufficiency to be effective as a true twin scroll.. I explained that in my first post regarding this topic, and even showed the variances. But I know that on the Evolution forums here, folks tend to be a bit hard in the head to hear different information that doesn't follow their course. So I won't beat the dead horse any longer. Believe as you will. In the meantime I'll continue to make turbochargers that can effectively eliminate that understanding little by little. But this was indeed an interesting discussion, and I did see several different perspectives. True twin-scroll in smaller properly developed wheel/housing combinations work. Big turbos with divided housings that were originally made for top end power, and tractor designs, are a bit different.Happy boosting everyone. Carry on.
Last edited by TheShodan; Sep 22, 2013 at 05:43 PM.
Actually, it's fact. Sure, there's radially divided (which we're more accustomed to) and sectionally divided (like on the Ford Powerstroke turbo and Audi R18 turbo), but hey, they both have two scrolls. 6 here, half a dozen there, same stuff. There are some more rare turbos like on the new 2014 VW/Audi 1.8L/2.0L engines which have two entries and a single volute, but no one calls those divided. In the turbo industry, it is common usage for divided and twin-scroll to mean the same thing. Sectionally divided is quite rare, so it would be called that specifically. But whatever, in the grand scheme of things, it's irrelevant.
Last edited by spdracerut; Sep 22, 2013 at 09:53 PM.
That's simply your opinion, and thank you. From the engineers at both Garrett and IHI that i worked with on several OEM and performance projects, they are not, but it takes a divided housing as a factor to become a twin-scroll housing (We didn't even call the divided housings that in the late 90s and early 2000s, yet people do now thanks to Full-Race's marketing team. ). A divided housing is a necessity to be a twin-scroll, not a sufficiency to be effective as a true twin scroll.. I explained that in my first post regarding this topic, and even showed the variances. But I know that on the Evolution forums here, folks tend to be a bit hard in the head to hear different information that doesn't follow their course. So I won't beat the dead horse any longer. Believe as you will. In the meantime I'll continue to make turbochargers that can effectively eliminate that understanding little by little. But this was indeed an interesting discussion, and I did see several different perspectives. True twin-scroll in smaller properly developed wheel/housing combinations work. Big turbos with divided housings that were originally made for top end power, and tractor designs, are a bit different.
Happy boosting everyone. Carry on.
). A divided housing is a necessity to be a twin-scroll, not a sufficiency to be effective as a true twin scroll.. I explained that in my first post regarding this topic, and even showed the variances. But I know that on the Evolution forums here, folks tend to be a bit hard in the head to hear different information that doesn't follow their course. So I won't beat the dead horse any longer. Believe as you will. In the meantime I'll continue to make turbochargers that can effectively eliminate that understanding little by little. But this was indeed an interesting discussion, and I did see several different perspectives. True twin-scroll in smaller properly developed wheel/housing combinations work. Big turbos with divided housings that were originally made for top end power, and tractor designs, are a bit different.Happy boosting everyone. Carry on.
^^^ I am pretty sure he was being ironic.
I still don't get the point The Shodan is trying to make with the difference between divided and twinscroll though. The pictures posted seem to directly contradict the point I think he's trying to make.
Aaron, which scroll exhibits higher pressure? The scroll closer to the turbine exit or closer to the CHRA?
I'm curious if MHI observed the same thing and had a fix for it as a system on the EVO...
This is a section cut on a 9.8 housing. That's not a visual effect, the scrolls are considerably different sizes all the way around the housing.
Interesting Tony1 noticed a loss of the TS benefits. So much for my pseudo TS manifold idea using a tial V-band housing...
I still don't get the point The Shodan is trying to make with the difference between divided and twinscroll though. The pictures posted seem to directly contradict the point I think he's trying to make.
Aaron, which scroll exhibits higher pressure? The scroll closer to the turbine exit or closer to the CHRA?
I'm curious if MHI observed the same thing and had a fix for it as a system on the EVO...
This is a section cut on a 9.8 housing. That's not a visual effect, the scrolls are considerably different sizes all the way around the housing.
Interesting Tony1 noticed a loss of the TS benefits. So much for my pseudo TS manifold idea using a tial V-band housing...
Last edited by 03whitegsr; Sep 23, 2013 at 02:29 PM.
^^^ I am pretty sure he was being ironic.
I still don't get the point The Shodan is trying to make with the difference between divided and twinscroll though. The pictures posted seem to directly contradict the point I think he's trying to make.
Aaron, which scroll exhibits higher pressure? The scroll closer to the turbine exit or closer to the CHRA?
I'm curious if MHI observed the same thing and had a fix for it as a system on the EVO...
This is a section cut on a 9.8 housing. That's not a visual effect, the scrolls are considerably different sizes all the way around the housing.
Interesting Tony1 noticed a loss of the TS benefits. So much for my pseudo TS manifold idea using a tial V-band housing...
I still don't get the point The Shodan is trying to make with the difference between divided and twinscroll though. The pictures posted seem to directly contradict the point I think he's trying to make.
Aaron, which scroll exhibits higher pressure? The scroll closer to the turbine exit or closer to the CHRA?
I'm curious if MHI observed the same thing and had a fix for it as a system on the EVO...
This is a section cut on a 9.8 housing. That's not a visual effect, the scrolls are considerably different sizes all the way around the housing.
Interesting Tony1 noticed a loss of the TS benefits. So much for my pseudo TS manifold idea using a tial V-band housing...
I wonder if they are tuned for velocity and the shortest paired runners are one scroll as opposed to the other to maintain exhaust speed
Last edited by 211Ratsbud; Sep 23, 2013 at 06:26 PM.
I bumped the thread but here is a back to back from the same car and same turbo, simply went twin scroll the second time around -
I felt I was at the octane limit both times and didnt go any higher than the 29.7psi on the twin scroll but that was something the twin scroll allowed that the single didnt...more boost.
I felt I was at the octane limit both times and didnt go any higher than the 29.7psi on the twin scroll but that was something the twin scroll allowed that the single didnt...more boost.
What's this business about typical turbos with t/s housings not being up to par? Can you slap any turbo with a t/s housing and bank? Assuming proper size housing is used.
Or does it come down to wheel geometry being designed around t/s housing?
Or does it come down to wheel geometry being designed around t/s housing?
Thus the reason I think the scroll towards the CHRA is larger on the mitsu, help balance out the pressure differential across the turbine wheel so that the exhaust valve area sees roughly the same back pressure on each cylinder during blow down. I wonder if the mitsu housing is a little exagerated on the area difference though to deal with the different runner lengths between 2&3 vs 1&4 as I beleive 1&4 are on the larger scroll. Could even make some sense on why the EVO sounds a little bit less like a tractor then the DSMs.
Last edited by 03whitegsr; Sep 24, 2013 at 03:19 PM.
More turbine wheel to drop pressure across...
Thus the reason I think the scroll towards the CHRA is larger on the mitsu, help balance out the pressure differential across the turbine wheel so that the exhaust valve area sees roughly the same back pressure on each cylinder during blow down. I wonder if the mitsu housing is a little exagerated on the area difference though to deal with the different runner lengths between 2&3 vs 1&4 as I beleive 1&4 are on the larger scroll. Could even make some sense on why the EVO sounds a little bit less like a tractor then the DSMs.
Thus the reason I think the scroll towards the CHRA is larger on the mitsu, help balance out the pressure differential across the turbine wheel so that the exhaust valve area sees roughly the same back pressure on each cylinder during blow down. I wonder if the mitsu housing is a little exagerated on the area difference though to deal with the different runner lengths between 2&3 vs 1&4 as I beleive 1&4 are on the larger scroll. Could even make some sense on why the EVO sounds a little bit less like a tractor then the DSMs.