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Location: Kita-Ku, Sapporo, Japan
Registered: January 2003
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Location: Newcastle
Registered: June 2002
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Re: SERIES Twincharging...
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Sun, 21 August 2005 15:11
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Location: Kita-Ku, Sapporo, Japan
Registered: January 2003
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Re: SERIES Twincharging...
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Sun, 21 August 2005 15:33
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AW11 no Jitsu wrote on Sun, 21 August 2005 03:01 | in issue 90 of Zoom there is a 13bt in a 323 that is running a 1g supercharger. The supercharger is used below 5000rpm to improve the response until the turbo kicks in.
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AW11 no Jitsu wrote on Sun, 21 August 2005 04:07 |
When the turbo comes up to speed, a solenoid-controled TB is opened and the electromagnetic clutch on the SC is disengaged.
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styler wrote on Sun, 21 August 2005 12:14 | how about checking out some oem setups like the nissan march super turbo and lancia,
'nissan march on autospeed'
At low-to-mid revs, the 930cc four is boosted by a positive displacement blower (see Supercharger Steal - Part One for details). At higher revs, however, a relatively large turbo kicks in to give great top-end performance. Note that the transitional stage is very smooth thanks to a relatively simple supercharger/turbo control system. At low rpm the turbo blows through the supercharger which is effectively free-wheeling. Then, at high rpm, the supercharger is disengaged by an electro-magnetic clutch and the turbo feeds the engine via a supercharger bypass passage. Airflow through this passage is controlled by a differential pressure valve which begins to open as the turbocharger nears operating speed
http://www.nissanperformancemag.com/august03/ask_s arah/
Known as twinchargers, the Lancia rally cars employed both a turbo and a supercharger. HKS even offered an upgrade for the Toyota MR2 with a supercharger-into-turbo kit.
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brett_celicacoupe wrote on Sun, 21 August 2005 14:54 |
here is my quick autocad design
it should give smooth trasition
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feral4mr2 wrote on Sun, 21 August 2005 19:59 | s/c blowing through the turbo is exactly how i would do it if i ever decide to try a twin charge set-up.
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toof wrote on Sun, 21 August 2005 20:15 | feral: exactly..
why not use the the charger to blow through the compressor housing of the turbo. yes it will offer some restriction however the plus is that you will be aiding the spooling of the turbo buy forcing air through both sides.then use a electronic controllable butterfly valve in a second pipe that bypasses the SC. as the turbo is at a point where it can/is making boost then open the electronic throttle (SC bypass) and turn off the charger.
my tuner and i considered this. the upwards transition is pretty straight forward to tune. its the downwards transition and partial throttle higher revs ie a sweepiong corner etc that will be difficult to tune.
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toof wrote on Sun, 21 August 2005 21:34 |
oldcorollas wrote on Sun, 21 August 2005 20:36 |
toof wrote on Sun, 21 August 2005 20:15 | feral: exactly..
why not use the the charger to blow through the compressor housing of the turbo. yes it will offer some restriction however the plus is that you will be aiding the spooling of the turbo buy forcing air through both sides.then use a electronic controllable butterfly valve in a second pipe that bypasses the SC. as the turbo is at a point where it can/is making boost then open the electronic throttle (SC bypass) and turn off the charger.
my tuner and i considered this. the upwards transition is pretty straight forward to tune. its the downwards transition and partial throttle higher revs ie a sweepiong corner etc that will be difficult to tune.
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but it has already been done.. that 13B for example.. anyway.. this is not the thread to discuss those ideas sorry.. make your own thread
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internal combustion has been done before and kinda works ok too
if you were going for the sequential the SC blowing through the turbo i imagine would be preferable to the turbo blowing through the SC. at least i would imagine it is.. since you can regain the SC's parasitic losses when the turbo is producing boost.
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[Updated on: Sun, 21 August 2005 15:35]
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Location: Kita-Ku, Sapporo, Japan
Registered: January 2003
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Re: SERIES Twincharging...
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Tue, 23 August 2005 13:50
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bump.. c'mon guys.. series aint that bad
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Location: Bundaberg, Qld.
Registered: May 2002
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Re: SERIES Twincharging...
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Tue, 23 August 2005 14:00
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this topic is old, Mods please delete.
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Location: Kita-Ku, Sapporo, Japan
Registered: January 2003
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Re: SERIES Twincharging...
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Tue, 23 August 2005 14:14
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feral4mr2 wrote on Wed, 24 August 2005 00:00 | this topic is old, Mods please delete.
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LOL, get over it
so anyway, Berad sent me this... which is similar to Bretts idea and sounds like the nissan march idea..
the beauty of this idea is that... the SC produces whatever pressure in the manifold it can... then as the turbo spools up, the intake pressure of the SC increases, which increases the manifold pressure more (and generates more SC heat..), you can stop the pressure increase happening by bleeding air back around the SC i guess...
so anyway, at some point the turbo will be producing the same pressure at it:s outlet that you want the SC to be making, and ths manifold pressure is still regulated by the bypass valve... at this point the SC is effectively free-wheeling, since the input and output pressure are the same.... and if the in and out pressure are the same, then the SC, although not havign much mechanical loss, could effectively be turned of, since it is just "spinning in the breeze" as it were...
by turning it of suddenly, you will have a sudden increase in air volume thru the bypass (or main as it should be called) pasage, but it will not be so bad, since the turbo was movign any air going thru the SC anyway...
the turbo should still spin up quickly as the SC is making heaps of exhaust gases, and so it should have the benefits of going parallel, with a fair amount of simplicity, but with the only downside of increasing SC temps from the turbo outlet/ higher SC outlet pressure perhaps....
if i wanted to series charge, i'd probably do it this way...
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Location: Kita-Ku, Sapporo, Japan
Registered: January 2003
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Re: SERIES Twincharging...
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Tue, 23 August 2005 14:16
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the main difference is that with bretts idea (as discussed in the other thread) is that SC losses will increase if you throttle the SC input.... and throttling it is not really needed anyway, since any air the turbo pushes has to get the the manifold somehow, and when on boost, you could even leave SC engaged, with the only downside being SC speed and temperature...
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Location: Bundaberg, Qld.
Registered: May 2002
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Re: SERIES Twincharging...
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Tue, 23 August 2005 15:05
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Quote: | LOL, get over it
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Location: Canberra
Registered: May 2002
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Re: SERIES Twincharging...
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Tue, 23 August 2005 22:57
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I'm sure it's been covered before, but, bloody work blocks so many images, but, this is my theory:
http://img371.imageshack.us/img371/4743/twinch30ew .jpg
It starts off with the SC blowing through the turbo (seperate linked TB on each end to keep everything happy).
Once the turbo comes on steam, it will start to outrun the SC. The one way valve opens allowing extra air to enter before the turbo, giving the turbo the extra air it needs and 'unloading' the SC.
You never switch the SC off, it's still turning, but as it has no pressure on either side, it won't be doing any work, and as it's just passing air rather than compressing it, hopefully, the airflow will cool the rotors.
The only problem I can see is the construction of the one way valve, I'm thinking a throttle body hooked up to an actuator from a vacuum secondary carbie should work though.
If you put the one way valve close to the turbo, you can minimise pumping losses as well.
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Location: Kita-Ku, Sapporo, Japan
Registered: January 2003
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Re: SERIES Twincharging...
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Wed, 24 August 2005 00:07
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image link is wrong but hasn't been covered yet
but i see what you mean.... it would unload the SC and you woul just get friction losses.... the whole dieing at 15psi or whatever is due to the inefficiency of the SC when compressing that much air, but i wonder what it could freewheel up to??? ie if you run at sayyy 12psi, will it be spinning too fast for it's bearings/gears at 8000rpm??
sounds good tho.. i can't think of any issues except the SC lifetime at high rpm, even tho it's unloaded.... it sound ssimilar to the system the guy with the 13B was using, except he simply turned the SC off and had all the air coming from the bypass/one way valve thingy...
maybe we should make a booklet with all these ideas
"Toymods Twincharge Techniques"!!
and as someone mentioned earlier, it would be easy to make all this modular, as it is just the piping that differs.... would make for an interesting (if busy when swapping pipes) dynoday
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Location: Canberra
Registered: May 2002
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Re: SERIES Twincharging... (no longer taking the piss :P )
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Wed, 24 August 2005 00:41
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OK - Does this image work?
Assuming you're not running the supercharger any faster than normal, it should last longer than a standard one does.
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I supported Toymods
Location: melbourne
Registered: June 2002
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Re: SERIES Twincharging... (no longer taking the piss :P )
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Wed, 24 August 2005 03:01
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I see great value in just turboing a 4AGZE/1GGZE without removing the supercharger, turbo blowing into the supercharger, one intercooler after the supercharger (possibly one pre supercharger so the poor little teflons dont melt off the supercharger)
it would be worth it just to have two boost gauges.
its not like they are expensive engines or anything.
then report back here.
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Location: brisbane
Registered: December 2004
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