New Outback... rear wheel steering?! (where have I been?)

[backwoodsboy]

Ok folks,

 

I was doing a little google surfing (for subarus of course) ...and I ran across THIS >>

 

http://findarticles.com/p/articles/mi_qa3764/is_199901/ai_n8832686

 

Normal comparison article, but I was puzzled at the next-to-last paragraph on page 1.

 

"The Outback includes extra-long wheel travel to help keep the wheels in contact with the ground even over very bumpy roads, and the rear wheels turn slightly with the car to help in cornering."

 

OK.... are they for real? Why havent I heard of this before?!

(or do I just need to get out more?)

[Legacy777]

Typically the "rear wheel steering" is accomplished simply by how the suspension is setup. It's not like the rear wheels have a steering rack.

 

I believe the honda accord has a similar setup. I'd be interested to know what they changed, if anything on the rear suspension.

[backwoodsboy]

It's not like the rear wheels have a steering rack.

 

 

Ok... I see. Much clearer.

 

Ive seen a few of the GMC trucks that have that 4 wheel steering stuff, and I thought "Oh no, not Subaru too!"

[CNY_Dave]

Typically the "rear wheel steering" is accomplished simply by how the suspension is setup. It's not like the rear wheels have a steering rack.

 

I believe the honda accord has a similar setup. I'd be interested to know what they changed, if anything on the rear suspension.

 

Meaning, you compress the rear suspension and the wheel toes-in a little bit?

 

 

Dave

[OB99W]

Meaning you can design multi-link rear suspension to change wheel angles as forces change. Yes, toe is controllable; see "Four-wheel steering", especially third paragraph, in http://en.wikipedia.org/wiki/Steering

[CNY_Dave]

Ah- a little toe-in added via the side force.

 

 

Dave

[Hondasucks]

I believe the honda accord has a similar setup. I'd be interested to know what they changed, if anything on the rear suspension.

It was the Prelude that had the four wheel steering (Earlier ones had a "4WS" badge) Early models had a mechanical link to the rear steering rack, later models were electronic, with an electric pump and valve body to control the rear wheels.

 

SVXes had 4WS in Japan, on some models. The early ones had a pump to control the rear wheels, but the later ones used a passive system that changed the rear toe during cornering.

 

I've seen a Galant with 4WS too, but they guy had the pump disconnected and the rear wheels locked straight ahead since it was so problematic.

 

I think Lexus had a 4WS system too but I'm not sure.

[crazyhorse001]

"Passive" 4WS started on the 2nd gen RX-7. There's a "toe link" that, as the suspension compresses, toes out the rear outside wheel. Conversely the same link toes in the other wheel as the body rolls. I can't say for 100% if the late model Leggys have the same type of setup. It's not based on the side loads, rather the travel of the suspension.

[subaruplatt]

Typically the "rear wheel steering" is accomplished simply by how the suspension is setup. It's not like the rear wheels have a steering rack.

 

I believe the honda accord has a similar setup. I'd be interested to know what they changed, if anything on the rear suspension.

 

Yes passive rear steering.

The rear wheels move in a swaying radius, swaying in the direction of the turn. This way you feel that there is some planting of the rear wheels and you can turn around them.

 

60s alpha romeo spiders had this.

Works like a compass in 90 degree turns.

Used to do 90 degree turns at near 60 mph speeds.