How does the ACD/TCS work? (specifically)
Sep 14, 2005, 09:35 PM
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How does the ACD/TCS work? (specifically)
So- I'm curious about the Evo's traction control system-
(strangly, I can't find any info about how it works)
(is there even a traction control system?)
Anyway- I'm wondering if the ACD is in tarmac mode, you can get any wheelspin-
Meaning, if I'm hard on the gas around a corner, will it let the rear end step out?
Can you do a nice 4wheel drift?
Can you spin around and around roasting them on wet pavement?
And how does that change in the gravel and snow modes?
I would imagine that in gravel/dirt mode, more wheelspin is allowed?
And in snow, less is allowed?
Can the traction control be totally disabled?
I find it strange that detailed information about the various ACD modes is lacking
Can anyone help?
(strangly, I can't find any info about how it works)
(is there even a traction control system?)
Anyway- I'm wondering if the ACD is in tarmac mode, you can get any wheelspin-
Meaning, if I'm hard on the gas around a corner, will it let the rear end step out?
Can you do a nice 4wheel drift?
Can you spin around and around roasting them on wet pavement?
And how does that change in the gravel and snow modes?
I would imagine that in gravel/dirt mode, more wheelspin is allowed?
And in snow, less is allowed?
Can the traction control be totally disabled?
I find it strange that detailed information about the various ACD modes is lacking
Can anyone help?
Sep 14, 2005, 10:48 PM
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ACD locks front and rear 50/50 whole time. (NO torq split, ACD never splits torq)
How ACD works:
When you turn the wheel in Tarmac mod-The ACD opens instantly
When you turn the wheel in Gravel mod-The ACD takes 2 to 3 seconds to open
When you turn the wheel in Snow mod-The ACD takes 4-5 seconds to open
SEARCH:
https://www.evolutionm.net/forums/sh...&highlight=ACD
https://www.evolutionm.net/forums/sh...5&page=1&pp=15
http://www.mitsubishi-motors.com/cor...001/13E_09.pdf
http://www.mitsubishi-motors.com/cor...001/13E_09.pdf
How ACD works:
When you turn the wheel in Tarmac mod-The ACD opens instantly
When you turn the wheel in Gravel mod-The ACD takes 2 to 3 seconds to open
When you turn the wheel in Snow mod-The ACD takes 4-5 seconds to open
SEARCH:
https://www.evolutionm.net/forums/sh...&highlight=ACD
https://www.evolutionm.net/forums/sh...5&page=1&pp=15
http://www.mitsubishi-motors.com/cor...001/13E_09.pdf
http://www.mitsubishi-motors.com/cor...001/13E_09.pdf
Originally Posted by Crazy4Cars
How does the Active Centre Differential system work?
Mitsubishi ACD - “active centre differential system” ACD is the new major technical feature that distinguishes the previous Evo 4-6 models from the new Evo 7 ACD is an extension of the technology used in for the anti yaw control systems (AYC) employed in various previous Mitsubishi models in the rear axle position. The ACD system comprises an electric motor, driving an oil pump which pressures an oil reservoir to a peak 16-bar pressure. This reserve of “SYSTEM PRESSURE” is fed to the piston of the ACD plate pack via a modulation (proportion) valve. The modulation valve is software controlled by the “ACD ECU (electronic control unit).
The control inputs for the ACD electronic control unit are
4 wheel speeds
G force both lateral and longitudinal
Throttle position – a variable value
Braking state - on or off
Steering angle – neutral position (straight ahead) and off centre position provided by 3 optical inputs generated by rotation of the steering wheel.
Handbrake state – on or off
System pressure – Hydraulic pressure state
Mode switch state – to select Gravel, Snow or Asphalt software strategy (maps)
We fitted a Motorsport logging system to the E7 RS test car during our 90 mile shakedown run of the new car (in the well knownYorkshire Forest complex) prior to the Network Q Rally GB. The test data from the ACD system has provided a full understanding of how the system functions and it’s efficency.
The “Gravel” and “Snow” software strategies are similar; Gravel has the highest ultimate locking value of the two. In “Asphalt” mode a unique software strategy is employed
The system is technically far superior to the preceding Evo models VC centre differential systems. The centre differential performing well and able to limit front to rear axle “slip” on full throttle to a mean of around 0.6% on a slippery gravel surface. To put this in perspective, a good condition VC unit on a Evo 4,5 or 6 would struggle to be better than 30% aggregate slip value, which is traction going out of the window.
Pressure can be introduced and lost within the ACD system at speeds surprisingly close to WRC car standards, which has allowed Mitsubishi engineers to use a complex and sophisticated software control strategy
Mitsubishi ACD - “active centre differential system” ACD is the new major technical feature that distinguishes the previous Evo 4-6 models from the new Evo 7 ACD is an extension of the technology used in for the anti yaw control systems (AYC) employed in various previous Mitsubishi models in the rear axle position. The ACD system comprises an electric motor, driving an oil pump which pressures an oil reservoir to a peak 16-bar pressure. This reserve of “SYSTEM PRESSURE” is fed to the piston of the ACD plate pack via a modulation (proportion) valve. The modulation valve is software controlled by the “ACD ECU (electronic control unit).
The control inputs for the ACD electronic control unit are
4 wheel speeds
G force both lateral and longitudinal
Throttle position – a variable value
Braking state - on or off
Steering angle – neutral position (straight ahead) and off centre position provided by 3 optical inputs generated by rotation of the steering wheel.
Handbrake state – on or off
System pressure – Hydraulic pressure state
Mode switch state – to select Gravel, Snow or Asphalt software strategy (maps)
We fitted a Motorsport logging system to the E7 RS test car during our 90 mile shakedown run of the new car (in the well knownYorkshire Forest complex) prior to the Network Q Rally GB. The test data from the ACD system has provided a full understanding of how the system functions and it’s efficency.
The “Gravel” and “Snow” software strategies are similar; Gravel has the highest ultimate locking value of the two. In “Asphalt” mode a unique software strategy is employed
The system is technically far superior to the preceding Evo models VC centre differential systems. The centre differential performing well and able to limit front to rear axle “slip” on full throttle to a mean of around 0.6% on a slippery gravel surface. To put this in perspective, a good condition VC unit on a Evo 4,5 or 6 would struggle to be better than 30% aggregate slip value, which is traction going out of the window.
Pressure can be introduced and lost within the ACD system at speeds surprisingly close to WRC car standards, which has allowed Mitsubishi engineers to use a complex and sophisticated software control strategy
Sep 14, 2005, 10:55 PM
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Originally Posted by AWDrift07
damn you beat me to it!
can you do a nice 4 wheel drift? hmm...i like grip.
Can you spin around and around roasting them on wet pavement? depends on tires...have you not seen that EVO IX MR video?
And how does that change in the gravel and snow modes? see above
I would imagine that in gravel/dirt mode, more wheelspin is allowed? see above
And in snow, less is allowed? see above
Can the traction control be totally disabled?
I find it strange that detailed information about the various ACD modes is lacking? what is strange i didnt have that problem...it took longer to be a dick on this post than it did to find the above info. like 2 mins.
Can anyone help? try helping yourself.
Sep 14, 2005, 11:20 PM
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Thanks for the info- I had read those threads (which was just a bunch of conflicting information) but somehow missed the link to the informative pdf-
But that still doesn't really answer my question- so there is no traction control system to speak of?
(i was assuming if there was one, it would be put in the ACD)
Meaning, something monitoring slip at the wheels, and redirecting torque/cutting throttle to disallow slip.
It sounds like there's not- with the active control just switching the center diff to open/locked...
But that still doesn't really answer my question- so there is no traction control system to speak of?
(i was assuming if there was one, it would be put in the ACD)
Meaning, something monitoring slip at the wheels, and redirecting torque/cutting throttle to disallow slip.
It sounds like there's not- with the active control just switching the center diff to open/locked...
Originally Posted by ashumo
i forgot some of his ?'s though...
can you do a nice 4 wheel drift? hmm...i like grip.
Can you spin around and around roasting them on wet pavement? depends on tires...have you not seen that EVO IX MR video?
And how does that change in the gravel and snow modes? see above
I would imagine that in gravel/dirt mode, more wheelspin is allowed? see above
And in snow, less is allowed? see above
Can the traction control be totally disabled?
I find it strange that detailed information about the various ACD modes is lacking? what is strange i didnt have that problem...it took longer to be a dick on this post than it did to find the above info. like 2 mins.
Can anyone help? try helping yourself.
can you do a nice 4 wheel drift? hmm...i like grip.
Can you spin around and around roasting them on wet pavement? depends on tires...have you not seen that EVO IX MR video?
And how does that change in the gravel and snow modes? see above
I would imagine that in gravel/dirt mode, more wheelspin is allowed? see above
And in snow, less is allowed? see above
Can the traction control be totally disabled?
I find it strange that detailed information about the various ACD modes is lacking? what is strange i didnt have that problem...it took longer to be a dick on this post than it did to find the above info. like 2 mins.
Can anyone help? try helping yourself.
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