Lextreme II
Active Member
What do you guys think of this setup?
Compound Turbo
- Thread starter Lextreme II
- Start date
The 1UZFE EGR Delete Kit is available for sale here.
charge density getting higher. thus more power.
10lb/m @ 5psi + 10lb/m @ 5psi = 20lb/m @ 5psi
When compound charging. You are adding in series. The effective pressure, and flow-rate out of one compressor is the starting point of another, instead of starting at ambient conditions.
Which brings us to one of the major advantages of this:
When you have that very dense charge that's already at a high pressure run into the second compressor. That compressor sees the incoming charge the exact same it would if tas not there.
It will compress it down exactly the same as it would. There's simply that much more to compress.
The resulting charge is much, much stronger. And... If you keep all your compressors in their maximum effeciancy islands. The charge temps don't become signifigantly worse. I'd always still intercool it but...
Yes Lextreme. You can compound charge on anything you want. In fact. Take your twin turbo & re-route it to compound charge. But I would greatly advise you to knock your daily driving boost psi on your wastegates down to 33% of their values now! If you were to leave them where they are & just route one into another & cool the both. You'd probably get atleast another 30% power gain out of that thing.
Bring on the water injection!
even then, i would think GRENADE!!!! MUAHAHAHAHA!!!!
Compound supercharging is common in the big time huge gas & diesel engines. I like the idea. 
I don't like the one turbine spilling into another. I think it would be better to pair off cylinders for equal size turbos.
My favorite is blowing a small turbo into a larger one. (But for god's sake, DSM intercoolers are tiny & like $10 at most. Use one LoL!) You could use a centerfugal supercharger also. You can also blow a centerfugal compressor into a roots blower.
People always thing you blow a big compressor into a small one, or a supercharger into a turbo. That's just not right.
Here's a supercharged mini with a small turbo added onto it!
Here's another.
I don't like the one turbine spilling into another. I think it would be better to pair off cylinders for equal size turbos.My favorite is blowing a small turbo into a larger one. (But for god's sake, DSM intercoolers are tiny & like $10 at most. Use one LoL!) You could use a centerfugal supercharger also. You can also blow a centerfugal compressor into a roots blower.
People always thing you blow a big compressor into a small one, or a supercharger into a turbo. That's just not right.
Here's a supercharged mini with a small turbo added onto it!
Here's another.
Rather than compound charging i want to see a variable vane turbocharger running on a petrol car - they're common on diesels and attempt to have the characteristics of a small turbo at low boost levels and a larger turbo at high boost levels by changing the geometry of the turbine blades...
striker
New Member
Now lets go one step further into the future, think hybrids.....
second turbo diving an alternator that charges the batteries from pure waste engergy which was otherwise vented to the atmosphere...
it's also allready done, look for T.I.G.E.R.S in google. they can get 17kwh and geus what sort of transmission is in use to get the extreme high rpm lowered down to drive the alternator? yep antonov rotrex again.
this is the way forward as long as pure fuelcell isn't availeble. a system like that on a lupo3L diesel would be able to 60km to the litre with t4 wheel motors.
scania has the compounding system on almost all of the freight truck engines nowadays.
for extreme power... no way!
grtz Thomas
second turbo diving an alternator that charges the batteries from pure waste engergy which was otherwise vented to the atmosphere...
it's also allready done, look for T.I.G.E.R.S in google. they can get 17kwh and geus what sort of transmission is in use to get the extreme high rpm lowered down to drive the alternator? yep antonov rotrex again.
this is the way forward as long as pure fuelcell isn't availeble. a system like that on a lupo3L diesel would be able to 60km to the litre with t4 wheel motors.
scania has the compounding system on almost all of the freight truck engines nowadays.
for extreme power... no way!
grtz Thomas
The neatest part is that the single forced induction Prius in the world was sueprcharged, then swaped for a turbocharger. It gained economy because the engine was much more power on its own under load - The ECU takes that power & just throws it back into the batteries instead of putting it on the ground. So the net effect is having a battery that is charged much more than normal. The car itself was no faster than before when the battery was charged. (The key being it stayed charged much longer with FI.)
But as far as driving something with a turbine I don't see the point. It's not as effecient as just a directly driven belt, and it's a big restriction on the exhaust. To not be a restriction you'd be running a huge turbine. At which point you'd have trouble getting the alt to spool - which would sorta defeate the purpose in my mind.
Besides, electronics are great, but they don't win power to weight against combustion engines. From R/C planes all the way through real cars.
Also keep in mind the power output of even big alternators. I'll spot you some power. 15v @ say 200amps peak. What good is that amount of power driving a motor on the drivetrain? That's only 3000watts. Now you can wind motors to differing turns & poles to give it diffrent powerband charicteristics (Think of it like changing gearing, or cams & ports for lack of a better explination).
That still only works out to around 4 horsepower.
Which is why all the real OEM hybrid cars weigh so damned much. While that alt would do a good job *charging* a system. To get any real power out of it, now you've got to add batteries that can tie together to give *real* power levels.
Look at the new Camry Hybrid for example. It uses a 645v electric motor. But what you pay attention to is the *batteries* that supply the motor. 245v & 121amps (30,000watts) All that weight just to get a 40 horsepower boost, when more than 150lbs less weight the 3.5L 2gr-fse has some 80-odd horsepower more. That's just to make the point
Applying that back to you. Regardles of how you drive an alternator. Even say two alts @ 15v supplying 600amps. That's still only around 12 horsepower worth of power.
Nothing is as effecient in creating & transferring power as a direct mechanical link is. The unfortunate aspect of that is converting to & from mechanical & electrical enginer & back is not that effecient in the end. Just like fluid couplings are not the most effecient way of doing things either. Which is a big problem with electric drive trickery. You need all the effeciancy you can get!
But that's not to say it's not a neat idea. If you could create 35 horsepower worth of electricity & put 20 of it on the ground (Beware. While just under 60% energy transfer sounds good. That is an extremey big task!!!!!!!!!).
That would overcome the aerodynamic drag of most of these cars @ around 70-75mph ish.
Sounds like an insane amount of work just to overcome aerodynamic drag for me!!! I'd be inclined to do it mechanically & cheap. Fab up some half-crap mounting of a tiny 40-60hp small diesel (Bobcat) turbo like an IHI rhc3 that will insessantly spool in day to day driving. But dont add fuel to the engine. Let the son of a bitch burn stioch (or leaner), and run lots of water injection.
You might even get a couple of mpg out of that cruising. Ofcorse you'd ahve to just completely bypass that anytime your foot touched the gas what-so-ever!
But as far as driving something with a turbine I don't see the point. It's not as effecient as just a directly driven belt, and it's a big restriction on the exhaust. To not be a restriction you'd be running a huge turbine. At which point you'd have trouble getting the alt to spool - which would sorta defeate the purpose in my mind.
Besides, electronics are great, but they don't win power to weight against combustion engines. From R/C planes all the way through real cars.
Also keep in mind the power output of even big alternators. I'll spot you some power. 15v @ say 200amps peak. What good is that amount of power driving a motor on the drivetrain? That's only 3000watts. Now you can wind motors to differing turns & poles to give it diffrent powerband charicteristics (Think of it like changing gearing, or cams & ports for lack of a better explination).
That still only works out to around 4 horsepower.
Which is why all the real OEM hybrid cars weigh so damned much. While that alt would do a good job *charging* a system. To get any real power out of it, now you've got to add batteries that can tie together to give *real* power levels.
Look at the new Camry Hybrid for example. It uses a 645v electric motor. But what you pay attention to is the *batteries* that supply the motor. 245v & 121amps (30,000watts) All that weight just to get a 40 horsepower boost, when more than 150lbs less weight the 3.5L 2gr-fse has some 80-odd horsepower more. That's just to make the point
Applying that back to you. Regardles of how you drive an alternator. Even say two alts @ 15v supplying 600amps. That's still only around 12 horsepower worth of power.
Nothing is as effecient in creating & transferring power as a direct mechanical link is. The unfortunate aspect of that is converting to & from mechanical & electrical enginer & back is not that effecient in the end. Just like fluid couplings are not the most effecient way of doing things either. Which is a big problem with electric drive trickery. You need all the effeciancy you can get!
But that's not to say it's not a neat idea. If you could create 35 horsepower worth of electricity & put 20 of it on the ground (Beware. While just under 60% energy transfer sounds good. That is an extremey big task!!!!!!!!!).
That would overcome the aerodynamic drag of most of these cars @ around 70-75mph ish.
Sounds like an insane amount of work just to overcome aerodynamic drag for me!!! I'd be inclined to do it mechanically & cheap. Fab up some half-crap mounting of a tiny 40-60hp small diesel (Bobcat) turbo like an IHI rhc3 that will insessantly spool in day to day driving. But dont add fuel to the engine. Let the son of a bitch burn stioch (or leaner), and run lots of water injection.
You might even get a couple of mpg out of that cruising. Ofcorse you'd ahve to just completely bypass that anytime your foot touched the gas what-so-ever!
That TIGERS thing is just another example of a tiny bit of research put down, and a retardily boatload of assumptions & marketing pushing it.
The rest of the time the exhaust is not particularly speedy, heat has almost NOTHING to do with the power provided in the exhaust to the turbine. And all this is for SO LITTLE promised gain in effeciancy of energy transfer. What's his name showed the largest A/C compressor Toyota uses is worth 9 horsepower on VS off. An M62 compressor only takes 13 horsepower to run 10,000rpm. Anyone ever turned one of those by hand VS turning an alt? It's not even close LoL! I mean what are they gunna do? Put a normal Alt on a clutch & run this one at cruise rpm?
I can maybe see the 10% economy gain under the best circumstances, but oh dear god. LoL! Why waste the weight, time, money & KISS method in doing so? I mean what are the biggest alts out now that aint water cooled, or super custom units? Like 300 amps @ 28v? That's the *best* sintuation I can believe, yet that's still only like 11 horsepower for all that weight & effort.
Oh there's an improvement LoL! 2mpg. I can get that swapping from 5w-30 to 5w-20 on this v6.
Bullshit. Completely... To start with. That's the kind of crap only seen around peak torque at WIDE OPEN THROTTLE when the average exhaust is expelling the exhaust at roughly 240-260feet per second. Around 76m/s.
The rest of the time the exhaust is not particularly speedy, heat has almost NOTHING to do with the power provided in the exhaust to the turbine. And all this is for SO LITTLE promised gain in effeciancy of energy transfer. What's his name showed the largest A/C compressor Toyota uses is worth 9 horsepower on VS off. An M62 compressor only takes 13 horsepower to run 10,000rpm. Anyone ever turned one of those by hand VS turning an alt? It's not even close LoL! I mean what are they gunna do? Put a normal Alt on a clutch & run this one at cruise rpm?
I can maybe see the 10% economy gain under the best circumstances, but oh dear god. LoL! Why waste the weight, time, money & KISS method in doing so? I mean what are the biggest alts out now that aint water cooled, or super custom units? Like 300 amps @ 28v? That's the *best* sintuation I can believe, yet that's still only like 11 horsepower for all that weight & effort.
I thought compound turbos used the compressed air of the first turbo to spool the seccond turbo (ie. connect the compressor outlet of the first one to the turbine inlet of the seccond one). Having a quick look, there are people that put pressure into the intake of the seccond turbo (like the first pic) with great results http://www.cumminsracing.com/ do it on their diesel dragster.
If both of the first turbo's outlets (cold and hot side) fed into the turbine inlet of the seccond turbo, then it would produce some extra boost! Would be really cool with a split entry turbo like off a GT4 celica/MR2.
If both of the first turbo's outlets (cold and hot side) fed into the turbine inlet of the seccond turbo, then it would produce some extra boost! Would be really cool with a split entry turbo like off a GT4 celica/MR2.
Lextreme II
Active Member
What is the advantage of compound turbos?
striker
New Member
charge density getting higher. thus more power.
robertk515
New Member
i am a diesel mechanic myself and have installed one of these compound turbo setups on a 24valve cummins in a friend of mines truck.
the turbos are setup so one turbo (right of the manifold) can spool almost immediatly to spin the other turbo almost instantly after the first one. on his truck, there is litterally ZERO lag in both turbos. and it can boost near 30 psi on his stock internals right off idle. it is basically mimicking a variable geometry turbo by using 2 turbos.
it now pushes somewhere in the range of 700 to 800 horsepower/1100 to 1200 ft/lbs of torque and can burn up 44 inch tires in 4 wheel drive. its pretty **** sweet.
the turbos are setup so one turbo (right of the manifold) can spool almost immediatly to spin the other turbo almost instantly after the first one. on his truck, there is litterally ZERO lag in both turbos. and it can boost near 30 psi on his stock internals right off idle. it is basically mimicking a variable geometry turbo by using 2 turbos.
it now pushes somewhere in the range of 700 to 800 horsepower/1100 to 1200 ft/lbs of torque and can burn up 44 inch tires in 4 wheel drive. its pretty **** sweet.
striker
New Member
hey,
take a look at what bankspower does with their drag diesels, it's bloody insane the torque that they produce.
www.bankspower.com
I understand that the presuere from #1 is not used to spin the the #2, it will make it spin offcourse but thats not the main target, they target seems to be to compress an allready very dense charge even further. so yes boost would be the anwnser but in a different matter.
grtz thomas
take a look at what bankspower does with their drag diesels, it's bloody insane the torque that they produce.
www.bankspower.com
I understand that the presuere from #1 is not used to spin the the #2, it will make it spin offcourse but thats not the main target, they target seems to be to compress an allready very dense charge even further. so yes boost would be the anwnser but in a different matter.
grtz thomas
Lextreme II
Active Member
Would this system work on pump gas?
Incorrect. When compound charging. One compressor feeds another compressor. You couldn't feed both a compressor, and turbine into the same place. Remember that the pressure restriction that esists infront of the turbine is normally 2-3 times the amount of compression seen on a turbo.
The best way to do it with multiple turbocharges. Is to feed each turbine with a set number of cylinders. Turbines do not like restrictions, and nothing is more restrictive in an exhaust than a turbine.
When you take two compressors in parralell to feed an engine. You are not adding pressure. You are simply adding the flow rates.
10lb/m @ 5psi + 10lb/m @ 5psi = 20lb/m @ 5psi
When compound charging. You are adding in series. The effective pressure, and flow-rate out of one compressor is the starting point of another, instead of starting at ambient conditions.
Which brings us to one of the major advantages of this:
When you have that very dense charge that's already at a high pressure run into the second compressor. That compressor sees the incoming charge the exact same it would if tas not there.
It will compress it down exactly the same as it would. There's simply that much more to compress.
The resulting charge is much, much stronger. And... If you keep all your compressors in their maximum effeciancy islands. The charge temps don't become signifigantly worse. I'd always still intercool it but...
Yes Lextreme. You can compound charge on anything you want. In fact. Take your twin turbo & re-route it to compound charge. But I would greatly advise you to knock your daily driving boost psi on your wastegates down to 33% of their values now! If you were to leave them where they are & just route one into another & cool the both. You'd probably get atleast another 30% power gain out of that thing.
Bring on the water injection!
even then, i would think GRENADE!!!! MUAHAHAHAHA!!!!
