4 Wheel Steering?

[Quakefire]

I was reading Mazda's history site, and they mentioned the second gen RX-7, or at least a model of, had four wheel steering. Has anyone efver seen this before?

[AusTexRex]

Nope. Research it and get back to us.

[Quakefire]

A MacPherson strut up front and all independent rear was used. Though Mazda had considered active four wheel steering after testing the concept, Kijima proposed an arrangement that would allow a small degree of rear steer to be created by the rear suspension as it reacted to cornering loads. The new idea was tried with initialy unpromising results and sluggish steering feel, but it was later found the problem Lay in the suspension bushing doing the exact opposite of what it was supposed to! A re- arrangement of the components solved the problem and the P747 mulke with the new rear suspension was tested back to back with the bench mark Porsche 944, the only problem occurred when Uchiyama crashed the Porsche after being taken by surprise by its lift off oversteer!
Case proven I guess.

The suspension design did seem to have a handling problem though, the car seemed to resist initial turn in. This little problem was solved by looking again at the active four wheel steer mule and inventing an alteration to the P747 cornering induced steer arrangement that would steer the rears in the same direction as the fronts for stability at high speed and steer the rears in the opposite direction to the fronts at lower speeds, the amount of movement being actually quite small at just a a few degrees. The resulting "Dynamic Tracking System Suspension" and "Triaxial Floating Hub" did however induce an increased level of noise, a problem overcome by mounting the rear suspension and final drive seperately on a rear subframe which itself was mounted to the chassis with rubber bushings of various hardnesses defined by their individual purpose, so if your second gen has rather more rear suspension noise than originally like me you know where to start looking!


This is the best I can find. The small degree of turning would be why no one has noticed it before, but still an interesting idea. Would this be why some people have trouble getting the. rear to swing out infront of the nose while drifting. Just a thought. Heres a link for the site I got it off of, has some very interesting development information


Site Here (http://www.rx7uknet.dircon.co.uk/rx7_fc3s.html)

[AusTexRex]

interesting, I'd never heard of this before

[Quakefire]

The rear wheels only turn a very small amount, only a degree or 2, so it would be hard to see. its very interesting, i wonder what the mechanism looks like to do this. Guess i'll find out when i buy my fc

[DongeR]

My vr4 has AWS and it only turns a few degrees, it does cause unpredictable oversteer and generally people tend to remove it when they go beef up their rear differential. Above 30 mph, that’s when the AWS works and I can feel it with a slight hint sway from the rear. Overall AWS was an okay idea. Honda preludes in the past had AWS which moved up to 17 degrees I recall.

Here’s a link to download a file about AWS by Whiteline Suspension

http://www.otsmotorsport.com/alizee/

[AusTexRex]

My friend's vr-4 AWS had a mind of it's own when the roads were wet, so we removed it.

[Taj]

In the rx7 i understand it as a kind of a sliding bushing. Not an active rear steering system.