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Old 14th November 2008, 19:01   #1
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mitsubishi misfiring system

hey people , I am guessing all of you have heard of this wonder of a system that mitsubshi use in their evo's to keep the turbo spooled up. basically its that puff puff exhaust note on those evos,thats the misfiring system at work.

Its truely amazing how this antilag system changes the entire theory on turbocharged cars . Its a killer of a system ..! To my knowledge i guess the evo's bypass part of the inlet air to keep the spooled up by using valves from the compressor which are controlled by the ecu .

also i heard that they retard timing a little when the throttle is closed to provide that excess pressure in the exhaust gas since the exhaust gas is given less time to expand . even when the throttle is opened pah there you have it boost from the compressor . no wonder they so good at wrc n even on track . I maybe wrong at something i said so people correct me if am wrong . thanks
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Old 15th November 2008, 02:19   #2
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I heard about this in the "Initial D" series but seems like very little is disscussed about it. Just know that this system help the car negotiate turns quicker.
But am glad you brought this up. Lets see what others have to say.


PS: I would really disagree with your signature:-D
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Old 15th November 2008, 02:40   #3
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Mitsubishi uses the a system that diverts the intake air to the exhaust to keep the turbo spinning,, and the ignition retard .
Prodrive uses a different technique , they inject small amount of fuel in the exhaust to keep the turbo spinning.
from what I have heard both techniques destroy the turbo. but give a great dirve.
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Old 15th November 2008, 11:42   #4
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They require much better quality of turbo material (strong but still precise and light ).
its hard on the exhaust manifolds because the exhaust temp rises about 60 degrees on an average . but still they do have a cut off system that stop the misfiring for a time period so that the temp stablizes to an extent .
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Old 15th November 2008, 17:41   #5
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The turbos used in this kind of system are very expansive usually the components are as expansive as a whole ball bearing turbo, the turbine wheel is made of ceramic [few companies in Japan manufacture these components] as well as the ball bearing is made of ceramic, to withstand the temperature but still they do not last for long [they need change every rally].
At present the companies are trying to develop plastic turbine and compressor wheels.
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Old 15th November 2008, 21:03   #6
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Ceramic turbines are used to reduce the interia of the turbine and because they have longer life spans . they are made to take high amount of mechanical stresses, rapid temperature changes, vibrations , rapid cooling too. they work even at 1400 degrees. the use of ceramics is for increasing reliability .

also rally cars change their turbos, cams and gaskets etc so often because they use very limited amount of oil for cooling their engines . that results in excess wear and tear of their engine components . the main thing that do not cope with the misfiring systems are the turbo intakes(headers) even though they are coated with ceramics to reduce heat transfer and reduced friction resultng in increased volumetric efficiency of the fluid . they tend to expand n contract so much that they crack or no more remain as a constant area duct to the gas .

plus with so many sponsors shelling out money why would you not change ?:-):-):-)

Basically its not possible to determine the stress conditions of various indivdual components in a system in turbine etc . Their trying to employ plastics reinforced with glass to make turbines better since they are lighter and also the thermostability is better over a increased temperature range . plastics housings and compressor wheels are used because they have better creep resistence to temperatures .

creep resistance,Best stiffness at high temperatures,Best fatigue resistance and reduced cost and reduced weight are the main advantages

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Last edited by Jaggu : 16th November 2008 at 00:03. Reason: Back to back posts
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Old 15th November 2008, 23:40   #7
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Good to know the functioning of this system. Is this system only used in their rally cars or it does come as an add-on option because i dont think it is a standard fitment.
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Old 16th November 2008, 02:02   #8
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Quote:
Originally Posted by aamir_subzero View Post
Ceramic turbines are used to reduce the interia of the turbine and because they have longer life spans . they are made to take high amount of mechanical stresses, rapid temperature changes, vibrations , rapid cooling too. they work even at 1400 degrees. the use of ceramics is for increasing reliability .

also rally cars change their turbos, cams and gaskets etc so often because they use very limited amount of oil for cooling their engines . that results in excess wear and tear of their engine components . the main thing that do not cope with the misfiring systems are the turbo intakes(headers) even though they are coated with ceramics to reduce heat transfer and reduced friction resultng in increased volumetric efficiency of the fluid . they tend to expand n contract so much that they crack or no more remain as a constant area duct to the gas .

plus with so many sponsors shelling out money why would you not change ?:-):-):-)

Basically its not possible to determine the stress conditions of various indivdual components in a system in turbine etc . Their trying to employ plastics reinforced with glass to make turbines better since they are lighter and also the thermostability is better over a increased temperature range . plastics housings and compressor wheels are used because they have better creep resistence to temperatures .

creep resistance,Best stiffness at high temperatures,Best fatigue resistance and reduced cost and reduced weight are the main advantages

Note from the Team-BHP Support Staff : Please use the "edit" button if posting within 15 minutes of the first post, instead of creating another back-to-back post
The turbine chips due to the system as there are small explosion near to the turbine wheel and also the bearing give away due to the stress.
I was talking about the entire turbine made of ceramic not coating. Ceramic costing of turbine as well as housing is done for thermal stability.
The biggest problem with ceramic turbine is mechanical strength is not that good.

Quote:
Originally Posted by abhik View Post
Good to know the functioning of this system. Is this system only used in their rally cars or it does come as an add-on option because i dont think it is a standard fitment.
Hey abhik, this system is used only on compition cars as there are a lot of drawbacks, there are EVOs running this system in japan but they to are highly modified cars by tuners to showcase thier skills. The ECU has to be the compition ECU with the program to run this system. And as mentioned earlier the exhaut manifold and the turbo both will be destroied in couple of hundered KMs.
Pro_drive showcase this technology in their P-1 car. listen to the sound it makes.
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Old 16th November 2008, 03:06   #9
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i said ceramic coated headers . i know turbines are made of ceramic .

Abhik: yes dude you can get these systems fitted aftermarket but they are very expensive and lot of work involved .
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Old 16th November 2008, 18:48   #10
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Quote:
Originally Posted by aamir_subzero View Post
...Its truely amazing how this antilag system changes the entire theory on turbocharged cars ....
Check this post out, it has a link to an article about the ALS system on WRC cars.

http://www.team-bhp.com/forum/motor-....html#post9196

cya
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