when going over 15 mph (i think) the rear wheels on a 4ws prelude turn the same way as the front, when taking a a sharp corner fast and hard, wouldn't that in a way make it harder to take that corner.. maybe i'm just having a brain fart but i was thinking about it and i'm stumped. .. i dunno

 

Why would it make it harder. If you ask the rear wheels to turn in the direction that you want to go, it can only help.

 

i thought it was like that for under 15mph (or watever speed and it also takes into consideration the steering wheel angle)

also in certain situations the wheels go against the direction of steering

<<wishes he had 4ws system in his 4th gen

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by petern101 &raquo;</TD></TR><TR><TD CLASS="quote">i thought it was like that for under 15mph (or watever speed and it also takes into consideration the steering wheel angle)

also in certain situations the wheels go against the direction of steering

&lt;&lt;wishes he had 4ws system in his 4th gen</TD></TR></TABLE>

Under 18mph the rear wheels turn the OPPOSITE direction as the front wheels.

Over 18, the rear wheels turn in the SAME direction.

Yes, the degree the rear wheels turn depends on the angle the front wheels are turned.

 

does it say in the helms that the cutoff point is 18mph?

 

ah see i learned something new today

 

say you are making a hard left corner, if the rear wheels turn left, just like the front, your momentum will go in the direction you aim the front wheels, instead of toward the outside of the turn, like it would if they turned the opposite.....

 

4ws

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//----//


but i heard the skyline BNR32 also has 4ws
in slow speeds it does like the prelude

but in high speeds the rear wheels turn WITH the front

\\----\\

\\----\\

makes for stable turning in higher speeds

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SnlpeR &raquo;</TD></TR><TR><TD CLASS="quote">4ws

\\----\\


//----//


but i heard the skyline BNR32 also has 4ws
in slow speeds it does like the prelude

but in high speeds the rear wheels turn WITH the front

\\----\\

\\----\\

makes for stable turning in higher speeds</TD></TR></TABLE>

hahah , its kinda confusing.

 

thats exactly what the prelude has....

 

up to 30 mph the wheels turn in the opposite direction the the fronts and then after 60mph they turn the same direction as the fronts

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SnlpeR &raquo;</TD></TR><TR><TD CLASS="quote">

\\----\\

\\----\\

</TD></TR></TABLE>

drift!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mgags7 &raquo;</TD></TR><TR><TD CLASS="quote">thats exactly what the prelude has....</TD></TR></TABLE>

Nope, the Skyline and 240SX HICAS do the OPPOSITE of what the Prelude does. The MPH is different too. I believe the Nissan cars even keep the wheels straight at a certain speed range. Not positive though. I do know that their wheels turn in the opposite direction as the Prelude.

 

the way i understood it, below 18mph the rear wheels always turned opposite the fronts. Above that, they will either turn with or opposite the fronts based on steering angle (turning with the fronts would be better for, say, changing lanes i'd assume, so at a small degree they turn with) and then if you go into a sharper turn at a high speed they turn opposite. I could very possibly be wrong about this, but I at some point read that and may have been misinformed.

 

as ive already said :
up to 30 mph the wheels turn in the opposite direction the the fronts and then after 60mph they turn the same direction as the fronts

i know, i have it
all of the 2.2's that came out in the UK have

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by AndyD &raquo;</TD></TR><TR><TD CLASS="quote">Nope, the Skyline and 240SX HICAS do the OPPOSITE of what the Prelude does. The MPH is different too. I believe the Nissan cars even keep the wheels straight at a certain speed range. Not positive though. I do know that their wheels turn in the opposite direction as the Prelude.</TD></TR></TABLE>
Exactly. Actually they turn shortly in opposite direction to put the rear in slight oversteer (it's like that on Skylines and 300ZX, not sure about Silvias). No relation with our 4WS.

BTW our electronic 4WS computes an ideal angle for the rear wheels based on VSS, front wheels angle, rear wheels angle, and steering wheel turning speed. As i found out on a race track it has some very interesting high speed behaviors..

 

interesting high speed behaviors?
in a good or bad way?

i knew the 4ws speed was more than 18...i always heard it was around 30-35mph

taking a turn at 30mph with the steering wheel fully turned will give you more understeer than oversteer

 

consider your rear wheel in a high speed corner, the pressure outwards from the center of the car, now turn that wheel the direction of teh turn slightly, wouldn't that then make the force onto the sidewall of the tire greater making it easier to roll onto the edge of the tire?

 

Interesting in a good way. It seems it makes a difference when you enter a hairpin turn or a fast curve: steering speed has an effect. I managed to put the car in a controlled drift, and i could repeat it at will (was not easy to break out of the drift though...).. I'd really like to datalog the outputs of the 4WS to see what happens really back there. I suspect that rear wheels can still turn opposite from front under some conditions (fast steering). Slow steering = parallel, really helps in fast curves, it's even impressive - i could outtake an integra type R in a fast curve, as i had far less understeer.
Note it's mainly behaviour at limits - i'd never try this on an open road.. as experience showed i'm still not able to keep the car on the track 100% of the time, and i have cumulated several days of racetrack experience.. it's safe to go off track on a race track, but not an open road !

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by fastfu &raquo;</TD></TR><TR><TD CLASS="quote">i know, i have it
all of the 2.2's that came out in the UK have</TD></TR></TABLE>

Well, then you don't know your car very well. HAHAHAHA

Here you go, and it's a Euro article too.

I love being right. :D

http://www.hilfe.mg-rover-club-berlin.de/134.htm

Search the page for "18". It should be half way down through the article.

 

from the article:
"And at medium speeds it depends on the steering input"
-&gt;this is where lies the "interesting behaviour"

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by AndyD &raquo;</TD></TR><TR><TD CLASS="quote">Nope, the Skyline and 240SX HICAS do the OPPOSITE of what the Prelude does. The MPH is different too. I believe the Nissan cars even keep the wheels straight at a certain speed range. Not positive though. I do know that their wheels turn in the opposite direction as the Prelude.</TD></TR></TABLE>

andy i was making no comment on the skyline or 240 system...i was just saying the above described system was like what the prelude has...

i wonder if 4ws is worth the weight on an all out racecar....

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Jesus_FR &raquo;</TD></TR><TR><TD CLASS="quote">from the article:
"And at medium speeds it depends on the steering input"
-&gt;this is where lies the "interesting behaviour"
</TD></TR></TABLE>

I think that boils down to the fact that you really don't turn the steering wheel too much at speed. But that's just my personal opinion.

Like I said, I have tracked my Prelude. The car is VERY predictable. VERY neutral too. It feels like a 50/50 weigth distributed car. However, I have not driven a regular 2WS Prelude on the track so i can't compare the two.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mgags7 &raquo;</TD></TR><TR><TD CLASS="quote">

andy i was making no comment on the skyline or 240 system...i was just saying the above described system was like what the prelude has...

i wonder if 4ws is worth the weight on an all out racecar....</TD></TR></TABLE>

Oh, ok.

I do know that the HICAS system in the 240SX is junk, as far as withstanding the test of time. Most say the car is unpredictable on the track. Most delete their HICAS system. There is even a company that makes a delete kit.

 

yeah i always hear that HICAS is crap from japan direct....whenever they get a silvia swap with HICAS they toss the rear end....