Triple turbo 3 rotor?
I actually have some documentation somewhere (Mazda documentation if im not mistaken) that says quite clearly that parallel turbo setup will produce more lower end torque versus the higher RPM torque of a large single turbo and spool substantially faster. So to summarize. Single turbo's will spool slower than an equivalent and properly engineered parallel setup. Parallels add some weight, and complication to a turbo build but not so much so that it can't be done or that the performance enhancements are negated. Yes your turbo efficiency can be effected by your choice of turbo chargers, and generally speaking a large single is the way to go. However! in a driving situation where fast response and large amounts of low end torque are necessary a twin system would be ideal.
Case in point. RE- Amemiya designed parallel twin turbo manifold. and Howard Coleman designed Parallel twin turbo setup.
Case in point. RE- Amemiya designed parallel twin turbo manifold. and Howard Coleman designed Parallel twin turbo setup.
Rotorhead
Joined: Feb 2001
Posts: 9,136
Likes: 39
From: Charlottesville, Virginia, USA
I think you have a good handle on it. Obviously the "flow" thing is bogus, lol.
If you are asking what I think about 3 turbos on a 3-rotor engine, I think it would be a great idea for a show car. However, I have my doubts that it would work well at lower engine rpms if each turbo were fed by only one runner, and it doesn't seem very practical to build a manifold log that would feed all three turbines equally.
V
V
V
If you are asking what I think about 3 turbos on a 3-rotor engine, I think it would be a great idea for a show car. However, I have my doubts that it would work well at lower engine rpms if each turbo were fed by only one runner, and it doesn't seem very practical to build a manifold log that would feed all three turbines equally.
V
V
Full Member
Joined: Oct 2006
Posts: 60
Likes: 1
From: New Zealand
multi turbo setups work great,apart from my higher boost race car I just finished a customers 13b(s6,stock intake,water to air) street car with twin turbo(.63 o trim,56mm comp) setup,one exhaust per turbo with twin gate setup. 11psi it makes 410whp at the treads on a dyno dynamics with an awesome broad power curve,best 13b Ive ever driven on the street as far as power delivery goes,looks and sounds awesome to which for a lot of people is very important,these are our hot rods after all
I dont care in the science of it all but seems to make a broader power with the twins,even in my twin turbo drag set up was alot nicer than the big single,hence why I put 3 on the 20b,oh and it looks and sounds the goods too
brent
I dont care in the science of it all but seems to make a broader power with the twins,even in my twin turbo drag set up was alot nicer than the big single,hence why I put 3 on the 20b,oh and it looks and sounds the goods too
brent
Senior Member
Joined: Nov 2008
Posts: 357
Likes: 0
From: Czech republic
multi turbo setups work great,apart from my higher boost race car I just finished a customers 13b(s6,stock intake,water to air) street car with twin turbo(.63 o trim,56mm comp) setup,one exhaust per turbo with twin gate setup. 11psi it makes 410whp at the treads on a dyno dynamics with an awesome broad power curve
brent
brent
Very nice results. Good to see that it works for you. Problem is that people here are comparing apples and oranges. They claim that twins spool faster but top end is better with single. So what will happen when we correctly size both setups to make same power? Spool up will be very same or better with single
So a bigger hit down low compared to the same hit higher in the revs. Pretty much apples to apples comparison there.
I think you have a good handle on it. Obviously the "flow" thing is bogus, lol.
If you are asking what I think about 3 turbos on a 3-rotor engine, I think it would be a great idea for a show car. However, I have my doubts that it would work well at lower engine rpms if each turbo were fed by only one runner, and it doesn't seem very practical to build a manifold log that would feed all three turbines equally.
V
V
V
If you are asking what I think about 3 turbos on a 3-rotor engine, I think it would be a great idea for a show car. However, I have my doubts that it would work well at lower engine rpms if each turbo were fed by only one runner, and it doesn't seem very practical to build a manifold log that would feed all three turbines equally.
V
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I think putting all the technical crap aside. Its a pretty badass looking setup. The same reason people 2jz....or LS... Its something different.
Where not on the subject of 13b's. For one, you have less room in the engine bay for all the expensive fabrication that would need to be done to make it work with the longer engine. I like that my car still has ABS. Plus you now have three potential turbos to replace if you blow the engine $$$. Also more components, more chances of failure. Do I need to keep going? Like I said before, if you have all this stuff lying around and the fabrication skills to build it, then do as you please. It's still not practical. Some people think if somethings not practical, then it's poinless.
Know one needs to be a scientist when you have references like these to help make a point. Single turbo 20b 1st gen.
https://www.rx7club.com/showthread.p...hlight=1st+gen
FWIW, I could care less about MAX hp.
Where not on the subject of 13b's. For one, you have less room in the engine bay for all the expensive fabrication that would need to be done to make it work with the longer engine. I like that my car still has ABS. Plus you now have three potential turbos to replace if you blow the engine $$$. Also more components, more chances of failure. Do I need to keep going? Like I said before, if you have all this stuff lying around and the fabrication skills to build it, then do as you please. It's still not practical. Some people think if somethings not practical, then it's poinless.
You mention "$$$" when replacing turbos should the engine go, if the 3rotor took a dive - 3 small-framed turbos aren't at the top of the list from a monetary respect. I'll admit something semi embarrassing - I spent over $3k on a monster GT47r for a 3rotor project. a 48lb turbo! I was too nervous/scared/whatever to finish the build with turbo. I took it off and sent it back. My thought was "If I broke this turbo, damn, I wouldn't want to shell out the cash to rebuild it and be $X into just one turbo".
3 TD06 / 20G (or a GT28r sized turbo) is a little cheaper than one big one - on that same note, these are so old and cheap nowadays it wouldn't even matter. A TD05 / TD06 is easier to swallow than a single GT47r from P/T.
My whole point to typing all this crap is - you might not agree with his quality of work or how he gets things done or his setup, etc etc but you have to hand it to him - he's actually trying this and is successful!! not bench racing his 6 second 1/4 mile armchair fueled by bullshit.
What I completely hate about this "community of car guys" (not specific to this forum - I'm encompassing all haters worldwide) is speed in which it takes for someone to say "thats a load of crap and is a stupid idea and probably wont work - you n00b". Well, sure w/e. Might be true to an extent but where is the support for someone wanting to build a stupid 3rotor/3turbo car? ..no where.. I've not read one single positive remark supporting anyone building / running a 3rotor engine with 3 turbos. These people are too quick to point out flaws and spout smokey yunick / corky bell (read: antiquated) remarks.
Sometimes you guys are too damn quick to bash without knowing half the story.
I can tell you this - once he finishes up with that car ... you would have to be a pure hater to not congratulate him on the goals reached and achievements.
1000 years, lost in time.
Joined: Oct 2007
Posts: 178
Likes: 1
From: Australia
Hey all,
Damn this has been interesting to read! Now if only I could read Chinese =) Have to admit the car looks great, which I personally think was the primary reason for doing it. Would have cost a bomb and been a logistical nightmare to get everything to fit! So the builder gets my *** for being out there and making a dream a reality, even if I'd never consider it. But hey, someone took pleasure in doing it, and as an engineer I appreciate the huge effort they went to. As for the practicality of the three turbo setup, noting comments re pulses and porting etc, I just want to make a few quick observations and comments...
Um, where's the cold air/ clear air intake for the three turbos? And where are the air filters for that matter? This engine, for all its beauty, isn't going to breath well or cleanly. There is now extra radiant heat under the bonnet from the extra turbos and DP's, and immediate reduced efficiency simply because the air to the intakes is by no means balanced. So seriously said, it may look cool, but how long is it practically going to last - and how efficient "can" it really be?
So turbo's are are great things. They get exhaust gases rush up to them, make friends, and spin like crazy. Then suck air like a sonofabitch stuck on a chicks lips on a first date, jam it into the engine and the cycle continues. But look at the bends this poor bastard has hard to use just to make it all fit. Bends cause resistance, resistance slows the air down, slower air means less power. But not just that, now you have a situation where all three turbo's are spinning at different rates as each has different levels of friction to overcome (assuming, which I don't think we can, that the manifold distributes the exhaust evenly and in a thermally efficient manner) - so you have created a problem you need to fix (or ignore) which is each turbo is generating different boost amounts - not to mention that their bearings will wear at different rates, again changing boost and further reduces efficiency.
Sure, on paper, three small turbo's can deliver comparable torque and power to a single spinner - if in both cases they are correctly size mated to the engine, expected gas flow and are correctly regulated. But don't think that if you have three small turbos that you are going to generate amazing torque early when compared to a single spinner. You have a third as much exhaust to start with per turbo, so it will take a comparable amount of time to boost up as a 3 rotor single turbo build would - assuming both builds are designed for the same overall torque and power. What I mean by that is simple: If you have a smaller turbo being fed by X cfm of gases, it will spin up quickly (ergo early torque), then peak out at its max efficiency (determined by its physical size), delivering Y power. The same engine with the same cfm of gases, now with a larger turbo, will take longer to spin up (aka turbo lag), delivering less power and torque early in the rev range, but because a larger turbo has a greater boost potential (and an efficiency range that is higher than a physically smaller unit), the ultimate power achieved will now be considerably greater. If you want early boost from sfa revs, then you need to shunt ALL the available exhaust gas to a small turbo first, before passing the gas to a second larger turbo when the revs/ load builds up. Mazda did it with valves and clever computers and bits and pieces that worked pretty well - for a while. But we normally chuck all that in place of a single spinner because, a) the Mazda stuff was bloody hard to get right and keep working properly, and b) because we can make much more power without sacrificing much (if any) torque by making the engines breath, spin, and flow better.
So does this car look great? Yes! Looks super cool. But would it stand up to a well balanced and mated single turbo 20B? Very unlikely, as from a design perspective it's already fighting its own design inefficiency.
Still, it looks great, which I think was the whole point it was done
Damn this has been interesting to read! Now if only I could read Chinese =) Have to admit the car looks great, which I personally think was the primary reason for doing it. Would have cost a bomb and been a logistical nightmare to get everything to fit! So the builder gets my *** for being out there and making a dream a reality, even if I'd never consider it. But hey, someone took pleasure in doing it, and as an engineer I appreciate the huge effort they went to. As for the practicality of the three turbo setup, noting comments re pulses and porting etc, I just want to make a few quick observations and comments...
Um, where's the cold air/ clear air intake for the three turbos? And where are the air filters for that matter? This engine, for all its beauty, isn't going to breath well or cleanly. There is now extra radiant heat under the bonnet from the extra turbos and DP's, and immediate reduced efficiency simply because the air to the intakes is by no means balanced. So seriously said, it may look cool, but how long is it practically going to last - and how efficient "can" it really be?
So turbo's are are great things. They get exhaust gases rush up to them, make friends, and spin like crazy. Then suck air like a sonofabitch stuck on a chicks lips on a first date, jam it into the engine and the cycle continues. But look at the bends this poor bastard has hard to use just to make it all fit. Bends cause resistance, resistance slows the air down, slower air means less power. But not just that, now you have a situation where all three turbo's are spinning at different rates as each has different levels of friction to overcome (assuming, which I don't think we can, that the manifold distributes the exhaust evenly and in a thermally efficient manner) - so you have created a problem you need to fix (or ignore) which is each turbo is generating different boost amounts - not to mention that their bearings will wear at different rates, again changing boost and further reduces efficiency.
Sure, on paper, three small turbo's can deliver comparable torque and power to a single spinner - if in both cases they are correctly size mated to the engine, expected gas flow and are correctly regulated. But don't think that if you have three small turbos that you are going to generate amazing torque early when compared to a single spinner. You have a third as much exhaust to start with per turbo, so it will take a comparable amount of time to boost up as a 3 rotor single turbo build would - assuming both builds are designed for the same overall torque and power. What I mean by that is simple: If you have a smaller turbo being fed by X cfm of gases, it will spin up quickly (ergo early torque), then peak out at its max efficiency (determined by its physical size), delivering Y power. The same engine with the same cfm of gases, now with a larger turbo, will take longer to spin up (aka turbo lag), delivering less power and torque early in the rev range, but because a larger turbo has a greater boost potential (and an efficiency range that is higher than a physically smaller unit), the ultimate power achieved will now be considerably greater. If you want early boost from sfa revs, then you need to shunt ALL the available exhaust gas to a small turbo first, before passing the gas to a second larger turbo when the revs/ load builds up. Mazda did it with valves and clever computers and bits and pieces that worked pretty well - for a while. But we normally chuck all that in place of a single spinner because, a) the Mazda stuff was bloody hard to get right and keep working properly, and b) because we can make much more power without sacrificing much (if any) torque by making the engines breath, spin, and flow better.
So does this car look great? Yes! Looks super cool. But would it stand up to a well balanced and mated single turbo 20B? Very unlikely, as from a design perspective it's already fighting its own design inefficiency.
Still, it looks great, which I think was the whole point it was done
Senior Member
Joined: Nov 2008
Posts: 357
Likes: 0
From: Czech republic
Um, where's the cold air/ clear air intake for the three turbos? And where are the air filters for that matter? This engine, for all its beauty, isn't going to breath well or cleanly. There is now extra radiant heat under the bonnet from the extra turbos and DP's, and immediate reduced efficiency simply because the air to the intakes is by no means balanced. So seriously said, it may look cool, but how long is it practically going to last - and how efficient "can" it really be?
Bends cause resistance, resistance slows the air down, slower air means less power. But not just that, now you have a situation where all three turbo's are spinning at different rates as each has different levels of friction to overcome (assuming, which I don't think we can, that the manifold distributes the exhaust evenly and in a thermally efficient manner) - so you have created a problem you need to fix (or ignore) which is each turbo is generating different boost amounts - not to mention that their bearings will wear at different rates, again changing boost and further reduces efficiency.
Theoretically, it could lead even to surge condition. Single wastegate would help, but then, point about separating pulses is moot
But don't think that if you have three small turbos that you are going to generate amazing torque early when compared to a single spinner. You have a third as much exhaust to start with per turbo, so it will take a comparable amount of time to boost up as a 3 rotor single turbo build would. But would it stand up to a well balanced and mated single turbo 20B? Very unlikely, as from a design perspective it's already fighting its own design inefficiency.
In loaded situation, spool up would be probably comparable, yet single will most likely perform better. In transient responsiveness, moment of inertia has big influence but so does pulsed exhaust flow. But with 1/3 worth of energy, moment of inertia of one turbo would have to be 1/9 of singles moment of inertia to accelerate at same rate. Exhaust pulses of RE can spin up things pretty sharply, but divided housings make this point also moot in case of 2-rotor.
I would be really glad if someone could post up some relevant info about superiority of multiple turbochargers in parallel, of course considering they can produce as much power as comparable single. Since I donīt see any reason they could
Joined: Mar 2001
Posts: 31,833
Likes: 3,232
From: https://www2.mazda.com/en/100th/
actually if you use internal wastegated turbos, then the manifold is actually very simple. i do agree it would take more time to find a place for everything to FIT.
yeah, and this forum is pretty good!
many many years ago, my friends built a twin single turbo FD setup. since they just used the car we have here to mock it up, and make sure it ran, it didn't get many miles, but yes the turbos will fight each other!
What I completely hate about this "community of car guys" (not specific to this forum - I'm encompassing all haters worldwide) is speed in which it takes for someone to say "thats a load of crap and is a stupid idea and probably wont work - you n00b".
I can tell you this - once he finishes up with that car ... you would have to be a pure hater to not congratulate him on the goals reached and achievements.
I can tell you this - once he finishes up with that car ... you would have to be a pure hater to not congratulate him on the goals reached and achievements.
many many years ago, my friends built a twin single turbo FD setup. since they just used the car we have here to mock it up, and make sure it ran, it didn't get many miles, but yes the turbos will fight each other!
Senior Member
Joined: Nov 2004
Posts: 627
Likes: 0
From: Fallston, MD
I just can't stand the typical know-nothing statement "twin turbos spool faster because they're smaller." I hear people say this a lot. No ****, they also have half the exhaust driving them.
I don't doubt that in an optimized setup, the overall lag of the individual setup could be less (then again, it could also be more) but I doubt that the real-world implications of it would be significant. Furthermore, fabricating the setup and getting it running right is going to be much easier with a single-turbo setup. I have all the respect in the world for someone that can pull this off, but the reality of such a setup is that I personally wouldn't even attempt it. Glad not everyone shares my opinion, though.
I don't doubt that in an optimized setup, the overall lag of the individual setup could be less (then again, it could also be more) but I doubt that the real-world implications of it would be significant. Furthermore, fabricating the setup and getting it running right is going to be much easier with a single-turbo setup. I have all the respect in the world for someone that can pull this off, but the reality of such a setup is that I personally wouldn't even attempt it. Glad not everyone shares my opinion, though.
My whole point to typing all this crap is - you might not agree with his quality of work or how he gets things done or his setup, etc etc but you have to hand it to him - he's actually trying this and is successful!! not bench racing his 6 second 1/4 mile armchair fueled by bullshit.
?????? I haven't made any comments on the quality of anyone's work. The OP wanted info and I posted my opinions on the subject. Now jamespond24 however got a little bent out of shape with my comments. Why I have no idea! Were talking about 20b applications and he comes in with his thoughts on a twin turbo set up for 13b???? This is the 20b section and the orginal question was 20b related. Search my post history if you want but I have never made ANY negative comments on twin turbo 13b set-ups. I have plans to build my own in the future. Now I will say this, I really shouldn't have used the word "pointless" in my 1st post. That opened up the can of worms.
But I do fell it's still not practical.
I can tell you this - once he finishes up with that car ... you would have to be a pure hater to not congratulate him on the goals reached and achievements.
I don't hate on rotorheads. I have a really special project going on myself.
1000 years, lost in time.
Joined: Oct 2007
Posts: 178
Likes: 1
From: Australia
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