I'll go ahead and pose that question. Is the new S-AYC system an adaptive system? i.e. If an Evo X owner starts reducing weight and alters the weight distribution, will the S-AYC system adapt to the different weight distribution and continue to allow the car to behave the same way in corners? Or is the programming based solely on the stock weight parameters?

 

That is a really good question man. I would sure like to understand the answer to that one myself. I wonder if we have any European guys here that have a lot of experience with the AYC system that may be able to share their experiences.

 

SAYC - Super Active Yaw Control

not really an adaptive system.
Weight of the car doesn't affect how it works, it acts like a limited slip diff, but instead of clutch packs / gears / viscous fluid (mechanincal) - the AYC is controlled electronically.
It uses an active differential to transfer torque to the wheels that have the best grip on the road.

Taken from Wikipedia:

"Active yaw control is based on a computer-controlled rear differential which can actively split torque based on input from various accelerometers in the vehicle measuring longitudinal and lateral g forces, steering, brakes and throttle position.[2] Where ABS brakes are fitted they too are included in the input parameters. It accomplishes this via two hydraulic clutches which can limit torque on individual axles. This system should not be confused with stability control systems which utilize the braking system of a vehicle by individually braking certain wheels to rotate and slow the car (such as Electronic Brakeforce Distribution). AYC is a performance-oriented system which aims to increase cornering speeds."

 

So if it's based off of accelerometers... it very well may be adaptive. See?

 

Yes, it would have to be an adaptive system. Think about the effects of multiple passengers and climate conditons have on the vehicle. If the car cannot at least adapt to these this at least in somepart, it would be rather pointless to even have it in the first place.

 

Therefore... reducing weight from the rear by taking out the heavy *** sub, spare tire, jack, replacing the battery with a lighter one, etc. should not adversely affect the handling of the car. STRIP AWAY! If this is true, then those guys that feel like being e-balling ****** about reducing weight in the rear can shut their sucks. Reducing weight can only be a good thing. Corner weighting a car for the track will only make things more efficient. There must be a limit to how far you can go before you've reached the limit of the system. It's probably a moot point though.

 

[QUOTE=Mmelmann;5338836]Therefore... reducing weight from the rear by taking out the heavy *** sub, spare tire, jack, replacing the battery with a lighter one, etc. should not adversely affect the handling of the car. STRIP AWAY! If this is true, then those guys that feel like being e-balling ****** about reducing weight in the rear can shut their sucks. Reducing weight can only be a good thing. Corner weighting a car for the track will only make things more efficient. There must be a limit to how far you can go before you've reached the limit of the system. It's probably a moot point though.[/QUOTE]

Exactly. But if you are going to rely on a computer to make the car perform than your not really pushing it anyway are you? And yes the system can only adapt so much in either way, up or down in weight.But if you are a track junky, than the less weight the better. Less weight is always going to improve the efficiency of the vehicle to a point. Still the best place to shed pounds is in un-sprung weight.

 

I don't mind pushing a car/plane/bike that has electronical aids one bit. I don't mind pushing a car/plane/bike that has no electronical aids either. The electronical aids will make me faster and safer... so bring them on.

You can still push a car with electronic aids (as long as it's not e-hiv ) all day you Evil-X muppet. Ever watch F1?

 

Ok, hold it. I asked the original question in the 70lbs thread, but what I wanted to know was if weight distribution, not weight itself, would screw with the AYC. Dropping weight is great for the track, any way around it, but would you want to keep the same distribution between front and rear? Would the car understeer more if you dropped weight in the rear but not the front?

By the way, I like the X. I don't even have my IX anymore, and I intend to get the X. I'm not sure why a tech question would be seen as X bashing...

EDIT: And who would bring passengers to the track? Its been explained several times that all the electronic goodies in the X are performance oriented, not safety oriented like other Mitsu vehicles.

 

Weight has an indirect affect on S-AYC and I don't think changing it would have a significant affect on how S-AYC responds since you can for the most part substitute the effect of weight change with road surface change. S-AYC only has it's sensors to go by and can't tell whether the increased/decreased grip at a wheel is due to road surface change or weight.

In one aspect, S-AYC can be considered rear wheel steering done through torque control rather then steering angle.

Where it's going to be interesting is how it responds to suspension changes that affect the transient response of weight transfer on the car. Things that would be noticeable in a slalom or emergency lane change test.

 

Weight/downforce affects how much lateral force the car can handle before losing grip, so will a lighter rear end still be manageable by the AYC system? Its all math in the computer. The algorithm(s) that determine when to do what may expect certain ranges for sensor values. If it gets something outside of a certain tolerance, will it just break down and cause undesired effects (like understeer, or something of the sort)?

 

"actively split torque based on input from various accelerometers in the vehicle measuring longitudinal and lateral g forces, steering, brakes and throttle position."

so there is acceleromaters-longitudal- lateral- sensors and steereng, brake and throttle POSITION sensors. And all that adds up to the right input.

Hmmm.... So the question is good. if you change whp and weight + suspension will the S-AWC work properly? Because those all numbers will be different from the factory. Not to mention the throttle - break- steering POSITION SENSOR measurments.
and all those data will be read and measured out from the factory values...

Example if you put racing pads then you will use different break position to slow down , specialy with R compound... Not to mention the sterreng angle if you upgrade the suspension ,swaybar etc. And you will mix allthose numbers for the S-AWC ecu.

That will be interseting how the car will adopt these things. Any opinion on that?

 

I asked this same question a couple days ago in the middle of another handling thread. Got the same answers on here...and they are all speculation.

Does anyone have real data or real articles from Mitsubishi that they could post so we have something real to work with?

Does anyone have any experience with the JDM IX that had AYC? If they didn't experience any issues, it might be safe to believe the X won't experience any issues.

 

the AYC is alot more simple then the S-AWC or even the S-AYC.

 

Yeah, I'm certainly wondering if less weight in the rear will cause AYC to lessen its efforts to throw out the rear end (since it will be easier to do so) and therefore allow for a greater chance that physics will win out and cause understeer when a heavier front end has more inertia.