Would this sequential twin turbo setup work (theoretically)?
07-02-2006, 06:22 PM
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Would this sequential twin turbo setup work (theoretically)?
I've been throwing this idea around in my head for a couple years, but I'm not real sure how it would actually work.
The purpose would be to have a large turbo that can sustain torque at the upper end of the RPM limit. However a turbo like that usually has less that stellar boost capabilities down low (2000-3000 RPM) where much of the daily driving is, not to mention the obvious lag as the turbo builds steam.
So my idea is to have a smaller turbo downstream. Most likely a slightly undersized turbo for what you need. The idea would be something that could build about 7 PSI around 2000-3000 RPM so that you don't have to downshift when driving around.
So the way it would work, is that during partial throttle the large turbo would not spool very much, thus the wastegate would direct all exhaust gas through the main turbo. The gas would then go to the smaller turbo which would spool quickly. This would give you instant boost, but at the same time make the engine seem artificially bigger to the first turbo and make it spool up quicker (like injecting nitrous to help spool up). The second wastegate would then limited to like 7 PSI (since 0.5 bar springs are common).
To keep the smaller turbo from over spooling you would probably need like 2 50mm wastegates (or 1 big wastegate if they make them around the 70mm range). 2x50mm would be about as much as cross-section as a 2.75" tube, factor in the smaller turbo itself and you've probably got 3" worth of passage way.
So some of my concerns about this setup. Once the smaller turbo starts boosting, the air will want to go to the path of least resistance which will be the throttle body because it will be pulling a vacuum, but what about the compressor of the bigger turbo. Since its spinning a little, will it at least keep the compressed air from going backwards through the compressor (in other words a big boost leak). But then at the same time, once the bigger turbo starts spooling up and hits like 18 PSI, will it try to back out through the smaller turbo thats only pushing 7 PSI?
Also how do these two pressurized sources combine? If the large turbo is running 18 PSI and the smaller turbo is running 7 PSI, does the "boost" maintain at 18 PSI, but the volume of air combines? So would you actually get more "power" at a given PSI because you would have more air to mix with fuel?
I know sequential twin turbo setups are nothing new, as several Japanese cars used them in the 90's, but they always have complex valves and stuff. I don't know if the valves are just to make it drive a certain a way or because of the concerns about boost leaks that I mentioned.
I'm not looking for a super duper 800HP setup here, I'm looking for something that gives good stable power all across the power band. And this is not with any particular engine in mind...well except maybe just a 4 cyl in general as thats what I like.
The purpose would be to have a large turbo that can sustain torque at the upper end of the RPM limit. However a turbo like that usually has less that stellar boost capabilities down low (2000-3000 RPM) where much of the daily driving is, not to mention the obvious lag as the turbo builds steam.
So my idea is to have a smaller turbo downstream. Most likely a slightly undersized turbo for what you need. The idea would be something that could build about 7 PSI around 2000-3000 RPM so that you don't have to downshift when driving around.
So the way it would work, is that during partial throttle the large turbo would not spool very much, thus the wastegate would direct all exhaust gas through the main turbo. The gas would then go to the smaller turbo which would spool quickly. This would give you instant boost, but at the same time make the engine seem artificially bigger to the first turbo and make it spool up quicker (like injecting nitrous to help spool up). The second wastegate would then limited to like 7 PSI (since 0.5 bar springs are common).
To keep the smaller turbo from over spooling you would probably need like 2 50mm wastegates (or 1 big wastegate if they make them around the 70mm range). 2x50mm would be about as much as cross-section as a 2.75" tube, factor in the smaller turbo itself and you've probably got 3" worth of passage way.
So some of my concerns about this setup. Once the smaller turbo starts boosting, the air will want to go to the path of least resistance which will be the throttle body because it will be pulling a vacuum, but what about the compressor of the bigger turbo. Since its spinning a little, will it at least keep the compressed air from going backwards through the compressor (in other words a big boost leak). But then at the same time, once the bigger turbo starts spooling up and hits like 18 PSI, will it try to back out through the smaller turbo thats only pushing 7 PSI?
Also how do these two pressurized sources combine? If the large turbo is running 18 PSI and the smaller turbo is running 7 PSI, does the "boost" maintain at 18 PSI, but the volume of air combines? So would you actually get more "power" at a given PSI because you would have more air to mix with fuel?
I know sequential twin turbo setups are nothing new, as several Japanese cars used them in the 90's, but they always have complex valves and stuff. I don't know if the valves are just to make it drive a certain a way or because of the concerns about boost leaks that I mentioned.
I'm not looking for a super duper 800HP setup here, I'm looking for something that gives good stable power all across the power band. And this is not with any particular engine in mind...well except maybe just a 4 cyl in general as thats what I like.
07-02-2006, 06:33 PM
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Re: Would this sequential twin turbo setup work (theoretically)? (Westrock2000)
When the small turbo spools it will push air through and surge the large turbo. When the large turbo spools it will surge the small turbo. None of the boost will ever make it to the engine, without a complex arrangement of 1-way valves, wastegates, etc. If you want to see a sequential turbo arrangement look at the twin turbo rotary engines.
07-02-2006, 06:56 PM
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Re: Would this sequential twin turbo setup work (beepy)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by beepy »</TD></TR><TR><TD CLASS="quote">When the small turbo spools it will push air through and surge the large turbo. When the large turbo spools it will surge the small turbo. None of the boost will ever make it to the engine, without a complex arrangement of 1-way valves, wastegates, etc. If you want to see a sequential turbo arrangement look at the twin turbo rotary engines.</TD></TR></TABLE>
See thats what I was thinking, but there are many parellel twin turbo setups in use where you have two pressure sources pushing into the same air space. But they seem to work fine...though they would ideally be operating at close to the same pressure levels.
See thats what I was thinking, but there are many parellel twin turbo setups in use where you have two pressure sources pushing into the same air space. But they seem to work fine...though they would ideally be operating at close to the same pressure levels.
07-02-2006, 06:58 PM
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07-03-2006, 04:43 AM
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Re: Would this sequential twin turbo setup work (wantboost)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by wantboost »</TD></TR><TR><TD CLASS="quote">compound charging would be better. look at the compund kits for turbo diesels</TD></TR></TABLE>
Ahh yes, I forgot about that possibilty. The one turbo feeds the compressor of the second turbo, therefore there is no possiblity of boost leak.
However now I REALLY wonder how the two combine. If the small turbo is boosting 7 PSI, what happens when it runs through the second one. Oh wait I think I see. Is this about what would happen.....
So in reality the bigger turbo has to work less, because its already presented with an offset pressure that closer to the final number wanted?
However now I'm thinking that the compressor of the smaller turbo would be the bottle neck of the flowing of the larger turbo. So maybe you would need a hybrid of somekind that has a large compressor that can flow 350-400HP worth of air, but still have the small turbine that will spool up well...maybe like a very low A/R T3/T04, like 0.36
Ahh yes, I forgot about that possibilty. The one turbo feeds the compressor of the second turbo, therefore there is no possiblity of boost leak.
However now I REALLY wonder how the two combine. If the small turbo is boosting 7 PSI, what happens when it runs through the second one. Oh wait I think I see. Is this about what would happen.....
So in reality the bigger turbo has to work less, because its already presented with an offset pressure that closer to the final number wanted?
However now I'm thinking that the compressor of the smaller turbo would be the bottle neck of the flowing of the larger turbo. So maybe you would need a hybrid of somekind that has a large compressor that can flow 350-400HP worth of air, but still have the small turbine that will spool up well...maybe like a very low A/R T3/T04, like 0.36
07-03-2006, 05:04 AM
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Re: Would this sequential twin turbo setup work (Westrock2000)
I'm thinking that as the big turbo starts spooling up, its going to be sucking alot of CFM from the smaller turbo. As a result that will lower the pressure inside that intermediate pipe, and as consequence the wastegate will direct more gas through the smaller turbo, so even though its only pushing 7 PSI, it could be spinning quite high as the RPM's build.
07-03-2006, 06:48 AM
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Re: Would this sequential twin turbo setup work (Westrock2000)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Westrock2000 »</TD></TR><TR><TD CLASS="quote">I'm thinking that as the big turbo starts spooling up, its going to be sucking alot of CFM from the smaller turbo. </TD></TR></TABLE>
^^^^^^^^^^^^^^^^^^^^^^^
What he said, if they are in series then the small turbo will have to flow the same lbs/min as the large turbo, just at a lower pressure, which would not be right. Bypass valves are relatively cheap, that's what I used for my dual-sequential turbo/SC setup. I'd envision a dual-sequential turbo setup something like this:
I'd probably put the VES valves in the respective downpipes though, depends on how the plumbing was fitting together, either end would stop the flow through the turbine. They make pretty big reed valves for motorcycles, so those should be affordable/available.
^^^^^^^^^^^^^^^^^^^^^^^
What he said, if they are in series then the small turbo will have to flow the same lbs/min as the large turbo, just at a lower pressure, which would not be right. Bypass valves are relatively cheap, that's what I used for my dual-sequential turbo/SC setup. I'd envision a dual-sequential turbo setup something like this:
I'd probably put the VES valves in the respective downpipes though, depends on how the plumbing was fitting together, either end would stop the flow through the turbine. They make pretty big reed valves for motorcycles, so those should be affordable/available.
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07-03-2006, 09:21 AM
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Re: Would this sequential twin turbo setup work (dornon13)
That wouldn't work. Your routing the compressed air from the 1st turbo (smaller) into the exhaust housing of the 2nd (bigger) turbo? The 1st turbo in your diagram is acting as an obstruction...not doing anything except putting a restriction in the system. You are throwing away that compressed air.
07-03-2006, 09:52 AM
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Re: Would this sequential twin turbo setup work (SE-Rawkus)
Find a bigger motor bay! If you used a large wastegate or two large wastegates you might be able to control boost while outflowing the small turbine.
07-03-2006, 11:08 AM
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Re: Would this sequential twin turbo setup work (Si Shane)
wouldnt the compressed air spool up the other turbine alot faster than exhaust gases? that was my thinking..the only way i see mine being practical is in a HUGE turbo that wouldnt spool on the engine normally..but i do see how it would be a waste
07-03-2006, 12:00 PM
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Re: Would this sequential twin turbo setup work (dornon13)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dornon13 »</TD></TR><TR><TD CLASS="quote">wouldnt the compressed air spool up the other turbine alot faster than exhaust gases? that was my thinking..the only way i see mine being practical is in a HUGE turbo that wouldnt spool on the engine normally..but i do see how it would be a waste</TD></TR></TABLE>
You have to flow lots of air around the small turbine while still controlling the RPMS of it. Your boost controll is also once more removed, since you are indirectly controlling EM2 pressure, if exhaustmanifold 2 is the piping between compresor 1 outlet and turbine 2 inlet.
The energy in the air before it has been heated and pressurized might not trade so equally with compressed air. You have to find people w/ experience. If it is not set up to properly meet some goal then it will work poorly.
You have to flow lots of air around the small turbine while still controlling the RPMS of it. Your boost controll is also once more removed, since you are indirectly controlling EM2 pressure, if exhaustmanifold 2 is the piping between compresor 1 outlet and turbine 2 inlet.
The energy in the air before it has been heated and pressurized might not trade so equally with compressed air. You have to find people w/ experience. If it is not set up to properly meet some goal then it will work poorly.
07-03-2006, 05:57 PM
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Re: Would this sequential twin turbo setup work (dornon13)
First off, I think I should say some of you need more MS Paint experience 
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dornon13 »</TD></TR><TR><TD CLASS="quote">wouldnt the compressed air spool up the other turbine alot faster than exhaust gases? </TD></TR></TABLE>
The advantage to the exhaust gas is that it is REALLY hot. When gas gets hot it takes up <much> more volume, even though its not actually a bunch of air. So a turbo maybe able to flow alot of air, but it will not be very hot so it will take up much less volume. Plus you have to get rid of the exhaust gas anyways, so you may as well do something with it as much as possible. It would be counter productive to use the effecient hot exhaust gas to spool a turbo to send ineffiecient cold air to drive another turbo. But you thought outside the box and thats good.
Also you would want the bigger turbo closest to the exhaust, because its going to need the most energy to get it going.
I began thinking about the wastegate setup. And I think it would have to be managed a little differently than normal. I have a Turbonetics Evolution wastegate on my car and it has two nipples on it. One gets hooked up to the turbo, and then they stress to leave the other one just open, unless you know that it needs to be hooked up differently (they mention an electronic boost controller as an example).
So I'm thinking that bottom port goes to the turbo to read the turbo outlet pressure, then the top port uses the atmosphere as reference. The atmosphere enters the inlet turbo and the wastegate keeps the turbo spooling until the boost level difference is achieved between the inlet and the outlet of the compressor. Normally that is exactly what we want.
However in the case of the compound turbos, I think the following problem would arise. The smaller turbo's wastegate would reference the atmosphere and boost to 7 PSI. As the second turbo comes online it would start to boost to 18 PSI, now since the incoming air is already at 7 PSI it would only have to boost 11 more PSI to reach a total of 18. However as the bigger turbo starts spooling up and eating up the air the first turbo is providing, the 7 PSI in-between the turbo's would start to fall (maybe to 5 PSI), so the first wastegate would start to let the first turbo spool up more to make up for that fact. However once the in-between pressure drops to 5 PSI, the second wastegate will notice that total pressure is now only 16 PSI and it will make the second turbo spool up to make up for that fact. But the first turbo will come back up to that 7 PSI, so the second one will then overshoot the 18 PSI target and slow down. This would create a constant war between the two wastegates trying to maintain their own pressures. But I think we can rework it so that they stay happy.
The first wastegate would use the atmosphere as reference and would be set to make the small turbo boost 7 PSI. The second wastegate would would then use that in-between pressure and boost 11 PSI for a grand total of 18 PSI. The second wastegate wouldn't care what the actual pressure in the in-between pipe was, just that there is an 11 PSI difference between the inlet and outlet of the bigger turbo. So as the bigger turbo starts "draining" the smaller turbo, the smaller turbo would react by providing more volume to maintain the pressure, and the second wastegate would never fight it.
Sound stable? Complex...hell yes! But this is all in the interest of thinking.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dornon13 »</TD></TR><TR><TD CLASS="quote">wouldnt the compressed air spool up the other turbine alot faster than exhaust gases? </TD></TR></TABLE>
The advantage to the exhaust gas is that it is REALLY hot. When gas gets hot it takes up <much> more volume, even though its not actually a bunch of air. So a turbo maybe able to flow alot of air, but it will not be very hot so it will take up much less volume. Plus you have to get rid of the exhaust gas anyways, so you may as well do something with it as much as possible. It would be counter productive to use the effecient hot exhaust gas to spool a turbo to send ineffiecient cold air to drive another turbo. But you thought outside the box and thats good.
Also you would want the bigger turbo closest to the exhaust, because its going to need the most energy to get it going.
I began thinking about the wastegate setup. And I think it would have to be managed a little differently than normal. I have a Turbonetics Evolution wastegate on my car and it has two nipples on it. One gets hooked up to the turbo, and then they stress to leave the other one just open, unless you know that it needs to be hooked up differently (they mention an electronic boost controller as an example).
So I'm thinking that bottom port goes to the turbo to read the turbo outlet pressure, then the top port uses the atmosphere as reference. The atmosphere enters the inlet turbo and the wastegate keeps the turbo spooling until the boost level difference is achieved between the inlet and the outlet of the compressor. Normally that is exactly what we want.
However in the case of the compound turbos, I think the following problem would arise. The smaller turbo's wastegate would reference the atmosphere and boost to 7 PSI. As the second turbo comes online it would start to boost to 18 PSI, now since the incoming air is already at 7 PSI it would only have to boost 11 more PSI to reach a total of 18. However as the bigger turbo starts spooling up and eating up the air the first turbo is providing, the 7 PSI in-between the turbo's would start to fall (maybe to 5 PSI), so the first wastegate would start to let the first turbo spool up more to make up for that fact. However once the in-between pressure drops to 5 PSI, the second wastegate will notice that total pressure is now only 16 PSI and it will make the second turbo spool up to make up for that fact. But the first turbo will come back up to that 7 PSI, so the second one will then overshoot the 18 PSI target and slow down. This would create a constant war between the two wastegates trying to maintain their own pressures. But I think we can rework it so that they stay happy.
The first wastegate would use the atmosphere as reference and would be set to make the small turbo boost 7 PSI. The second wastegate would would then use that in-between pressure and boost 11 PSI for a grand total of 18 PSI. The second wastegate wouldn't care what the actual pressure in the in-between pipe was, just that there is an 11 PSI difference between the inlet and outlet of the bigger turbo. So as the bigger turbo starts "draining" the smaller turbo, the smaller turbo would react by providing more volume to maintain the pressure, and the second wastegate would never fight it.
Sound stable? Complex...hell yes! But this is all in the interest of thinking.
07-03-2006, 06:45 PM
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Re: Would this sequential twin turbo setup work (Westrock2000)
seriously. youre thinking about this too hard.
small turbo feeds big turbo on the exhuast side and big turbo feeds small turbo on the compressor side. if it works on diesels to produce over 100psi itll work in this app too
small turbo feeds big turbo on the exhuast side and big turbo feeds small turbo on the compressor side. if it works on diesels to produce over 100psi itll work in this app too
07-04-2006, 02:09 AM
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Re: (GrnTurtle)
Compounding two compressors will output VERY high air temperatures.
Also, when combining, you don't "add" pressure. Each turbo will be operating at a given pressure ratio, i.e., the ratio of inlet to outlet pressure. Your wastegate simply stops you rising up a compressor map (pressure ratio on vertical axis) whenever you get to an appropriate boost.
In the only example with numbers, the pressure ratio of the smaller turbo is 1.5, for an "extra 10psi" you are going from 1.5bar to around 2.15bar = pressure ratio of 1.433... which is a very low pressure ratio for efficiency in a big compressor. You'd want to be boosting really big in the big turbo, which then compounds to give insane boost, severly over-flowing the smaller turbo (well it will try to, but simply won't happen).
Compound will just not work in this situation. You will never find a small turbo which can flow enough. Just like you'll never find a large turbo who'll spool early enough (i.e. the initial problem). Each turbo will be flowing the same ammount of air. The closer to the same size the turbo's are, the better it will work (as they will both be operating in the same efficiency range, allowing for massive boost [at the cost of intake temperatures]), but the less desirable the solution comes to the problem.
I vote for the valves method.. Could be cool... Or twin-charge......
Also, when combining, you don't "add" pressure. Each turbo will be operating at a given pressure ratio, i.e., the ratio of inlet to outlet pressure. Your wastegate simply stops you rising up a compressor map (pressure ratio on vertical axis) whenever you get to an appropriate boost.
In the only example with numbers, the pressure ratio of the smaller turbo is 1.5, for an "extra 10psi" you are going from 1.5bar to around 2.15bar = pressure ratio of 1.433... which is a very low pressure ratio for efficiency in a big compressor. You'd want to be boosting really big in the big turbo, which then compounds to give insane boost, severly over-flowing the smaller turbo (well it will try to, but simply won't happen).
Compound will just not work in this situation. You will never find a small turbo which can flow enough. Just like you'll never find a large turbo who'll spool early enough (i.e. the initial problem). Each turbo will be flowing the same ammount of air. The closer to the same size the turbo's are, the better it will work (as they will both be operating in the same efficiency range, allowing for massive boost [at the cost of intake temperatures]), but the less desirable the solution comes to the problem.
I vote for the valves method.. Could be cool... Or twin-charge......
07-04-2006, 02:28 AM
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Re: Would this sequential twin turbo setup work (theoretically)? (Westrock2000)
This thread is pretty thought prevoking.... but wouldn't that setup be a waist even if it did work. First off i doubt that you could fit that in a honda engine bay... secondly wouldnt it produce much more boost than you actually needed.
07-04-2006, 05:03 AM
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Re: (string)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by string »</TD></TR><TR><TD CLASS="quote">Compounding two compressors will output VERY high air temperatures.</TD></TR></TABLE>
I was thinking about that, because basically you would be double compressing. Which means the air would get heated up twice.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">
Also, when combining, you don't "add" pressure. Each turbo will be operating at a given pressure ratio, i.e., the ratio of inlet to outlet pressure. Your wastegate simply stops you rising up a compressor map (pressure ratio on vertical axis) whenever you get to an appropriate boost.
</TD></TR></TABLE>
So then what I was saying about the Wastegate was wrong? Does it not work by simply comparing the reference (inlet) and the outlet, and then regulating to the set boost level? A turbo normally works by adding pressure to the constant pressure of the atmosphere.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by BigAl1911 »</TD></TR><TR><TD CLASS="quote">Wouldn't that setup be a waist even if it did work. First off i doubt that you could fit that in a honda engine bay... secondly wouldnt it produce much more boost than you actually needed.</TD></TR></TABLE>
Oh, I'm not saying this wouldn't be an exercise in gross excess...thats the fun
I think the most non-intrusive place for the second turbo would maybe be back in the muffler area (akin to STS turbo's). You would have to undersize the turbo AR to make up for the heat.
I don't think this would be a practical alternative. I just wanted to put a little thought into it. Honestly in my case since I have a standard T3/T04, I could probably achieve very similar results as this setup by upgrading to a dual ball bearing GT30R with maybe a 0.48 AR. That would give me the power output I want, plus the spool would improve.
I was thinking about that, because basically you would be double compressing. Which means the air would get heated up twice.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">
Also, when combining, you don't "add" pressure. Each turbo will be operating at a given pressure ratio, i.e., the ratio of inlet to outlet pressure. Your wastegate simply stops you rising up a compressor map (pressure ratio on vertical axis) whenever you get to an appropriate boost.
</TD></TR></TABLE>
So then what I was saying about the Wastegate was wrong? Does it not work by simply comparing the reference (inlet) and the outlet, and then regulating to the set boost level? A turbo normally works by adding pressure to the constant pressure of the atmosphere.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by BigAl1911 »</TD></TR><TR><TD CLASS="quote">Wouldn't that setup be a waist even if it did work. First off i doubt that you could fit that in a honda engine bay... secondly wouldnt it produce much more boost than you actually needed.</TD></TR></TABLE>
Oh, I'm not saying this wouldn't be an exercise in gross excess...thats the fun
I think the most non-intrusive place for the second turbo would maybe be back in the muffler area (akin to STS turbo's). You would have to undersize the turbo AR to make up for the heat.
I don't think this would be a practical alternative. I just wanted to put a little thought into it. Honestly in my case since I have a standard T3/T04, I could probably achieve very similar results as this setup by upgrading to a dual ball bearing GT30R with maybe a 0.48 AR. That would give me the power output I want, plus the spool would improve.
07-04-2006, 06:13 AM
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Re: (sc4dr)
If you guys would figure the pounds/minute of air that you will need to flow with a compounded solution and apply it to the compressor maps of a couple of turbos that you would like to use for this application (a fast-spooling one and a big-power one), then you'd quickly see why compounding might have some problems.
07-04-2006, 08:44 AM
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Re: Would this sequential twin turbo setup work (wantboost)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by wantboost »</TD></TR><TR><TD CLASS="quote">seriously. youre thinking about this too hard.
small turbo feeds big turbo on the exhuast side and big turbo feeds small turbo on the compressor side. if it works on diesels to produce over 100psi itll work in this app too
</TD></TR></TABLE>
Flowing the 1000hp of air through a "fast spooling" or "small" turbine will be troublesome.
small turbo feeds big turbo on the exhuast side and big turbo feeds small turbo on the compressor side. if it works on diesels to produce over 100psi itll work in this app too
</TD></TR></TABLE>
Flowing the 1000hp of air through a "fast spooling" or "small" turbine will be troublesome.
07-04-2006, 08:50 AM
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07-04-2006, 09:09 AM
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Re: Would this sequential twin turbo setup work (wantboost)
There was a dodge cummins diesel in an older off road magazine (I think) that had a compounded turbo setup and was running something like 150psi and made 3500ft/lb of torque or some ridiculous number like that.