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I'm pretty sure HICAS works by either steering the rear wheels out of phase with the fronts to sharpen turn in response at low speeds, or in phase to reduce understeer at high speeds. They don't turn much, only a couple of degrees, but you can definitely feel the rear end moving around with the HICAS working.

Edited by Big Rizza

Big Rizza is right, it uses a combination of steering wheel angle, speed and lateral force sensors to determine the angle to set the back wheels to.

Aswell as making turning response sharper is also tries to correct oversteer, the best example of this I've seen is the gtr special top gear did. Clarkson had a big drift going and as soon as he went to correct it you could see the rear snap into place, looked cool and great for normal driving but you can see why people use lock bars :D

^^^just to clear up any misunderstandings some people might have...

That would be the Super HICAS off a gtr

HICAS found on gtst's work on the same principle, but only the rear wheels move as opposed to all four with super hicas.

Whered you get that great pic from lbfalcon??

Poombah.. HICAS found on gtst's work on the same principle, but only the rear wheels move as opposed to all four with super hicas.

Think about what you said - of course all 4 move, the front 2 are controlled by you.. the back 2 by HICAS, the main difference is the number of degrees that the rear wheels move - super hicas is up to +/-1 degree I think, vs normal hicas is only +/-0.5degrees

Links.

They can move more than 1 degree.

I think it's more like 1.5 degree normally. The R34 can do a little dance when you reset the hicas, and it moves much more than 2 degrees when it's reseting itself.

hehe the pic was one that I posted of the translation I did of the Super HICAS system which comes in R33 GTSt's. The original image came out of the R33 GTSt sales brochure.

Big Rizza is right, it uses a combination of steering wheel angle, speed and lateral force sensors to determine the angle to set the back wheels to.

Aswell as making turning response sharper is also tries to correct oversteer, the best example of this I've seen is the gtr special top gear did. Clarkson had a big drift going and as soon as he went to correct it you could see the rear snap into place, looked cool and great for normal driving but you can see why people use lock bars :D

I was under the impression that, the particular event where Clarkson had the drift going was at relatively low speed exiting a second gear corner at full throttle. I thought he was demonstrating the ATTESSA system, and he was holding the drift in second gear out of the corner until the front gripped and immediately straightened him up. I have only seen the clip once on T.V ages ago before I even had my learners, that was all I remember.

Poombah.. HICAS found on gtst's work on the same principle, but only the rear wheels move as opposed to all four with super hicas.

Think about what you said - of course all 4 move, the front 2 are controlled by you.. the back 2 by HICAS, the main difference is the number of degrees that the rear wheels move - super hicas is up to +/-1 degree I think, vs normal hicas is only +/-0.5degrees

My bad. Should've elaborated more...

I know what you said but what I meant with 'same principle' is that they both steer wheels to adjust the car :(

hehe the pic was one that I posted of the translation I did of the Super HICAS system which comes in R33 GTSt's. The original image came out of the R33 GTSt sales brochure.

So you're saying T's came with S-hicas also? If so, then I should've looked a little harder when buying my car :(

If you think of a Skyline as what its supposed to be... ie a sporty passenger car, then HICAS is awesome. If you take a corner too fast it kicks in and helps you keep the car in control and back on line.

If you're a fully sick drifter or die hard trackday warrior, then HICAS is like going on a date with a hot chick and having your mom run upto your car to give you a scarf so you don't catch a cold... ie... nice thought, but totally useless. You want to control your car one way, and HICAS wants to help so it makes your car go the other way.

ATTESA stands for "Advanced Total Traction Engineering System for All Electronic Torque Split" = torque distribution

HICAS stands for "High Capacity Active Steering" = steering

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