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dickyf
06-03-2012, 11:12 AM
my question to the group is 'does having power steering or not on the NSX make a great deal of difference?'
does anyone have any experience of driving both?
thanks in anticipation

Problem Child
06-03-2012, 08:23 PM
I am sure that the purists will say that in order to feel the car you shouldn't have power steering but lets be real about this its hard enough driving on our roads today so I am all for power steering, ABS etc etc.

Whenever I drive cars today without PS I am glad I dont have one and I am sure I'd feel the same if my NSX didnt have power steering. My NSX doesnt feel any less an NSX because I have power steering! Its still a cracking drive!

nobby
06-03-2012, 10:14 PM
i have non pas and i agree with Geoff that its nice to have pas etc ... however in the NSX i prefer it being non pas ... it does provide great feedback and is only a chore when parking but its not that bad due to the weight of the car; even my wife does not complain about it! :) not going to wax lyrical to u about non ... both have pros and cons and is very much down to personal pref.

i have driven both variants and to me i find the pas version too light but again that's expected. i did make a change to the type r set up and this made a massive difference to feel of driving etc and more responsive

one of the reasons i chose non pas was to remove the potential issue of something going wrong and paying mega bucks for Honda parts. there are write ups on prime re issues/failures etc.

it will be down to personal preference at the end of the day.

perhaps more knowledgeable drivers can provide u more insight etc

Senninha
06-03-2012, 11:00 PM
Hi,

I've driven both and own EPS version. I actually drove a couple unassisted NSX and both were great on the open road, however, years of PAS cars meant that the NSX just didn't inspire confidence below 25/30mph. Purely a personal observation.

IIRC, unassited cars are the 91/93 cars, all after this have assistance apart from a handful of JDM imports.

regards, Paul

dickyf
06-03-2012, 11:19 PM
thanks for the replies. it seems to be a case of horses for courses.

m666 edd
07-03-2012, 10:59 AM
I know the lock to lock on the nsx is extremly large / slow. Do the PAS nsxs have a smaller lock to lock? I do find the amount of steering wheel turning required on tighter turns a pain but I guess on the otherhand at high speeds the additional precision and effort required probably helps you from driving the car past the limit so easily.

markc
07-03-2012, 12:56 PM
I know the lock to lock on the nsx is extremly large / slow. Do the PAS nsxs have a smaller lock to lock? I do find the amount of steering wheel turning required on tighter turns a pain but I guess on the otherhand at high speeds the additional precision and effort required probably helps you from driving the car past the limit so easily.

The rack ratios of the manual and EPS systems are similar overall. The road wheels actually turn by the same amount so the amount of steering wheel movement or "arm twirling" is also similar. The rack on the EPS system is of course also variable, it's "slower" in the centre and "faster" as you put on more lock. The power assistance is also variable meaning it provides most assistance at very low speeds and almost none beyond 30 mph. The EPS also filters out most of the bump steer (very little) and kickback that the NSX has which is the main reason people say the manual system has more feel. However the suspension/steering geometry of the NSX ensures that the steering weights up very considerably on lock at higher speeds. The EPS helps considerably with this but any NSX gets pretty physical to drive really hard for any period of time, on track (days) for example.

Having sampled both systems on road and track, the weight at parking is the most obvious differance that you notice on a test drive but I find the latter (less weight on lock at speed) to be biggest plus of the EPS cars.

Fitting a smaller steering wheel makes a surprising amount of differance to both "feel" and perceived arm twirling. I have (re)fitted a 350mm Momo Tuner wheel similar to the NSX-R and the 15mm drop in diameter, standard wheel is 365mm, makes more difference than you'd think. Lock to lock doesn't change but the distance your hand/arm moves does. This also makes the steering that bit heavier so is probably more suited to the EPS equipped cars, which conversely the NSX-R wasn't! In fact the Type S, like mine but without the airbag wheel option, was probably the only factory NSX to come with EPS and 350mm steering wheel :cool:

Having read the technical article in this months "evo" mag on Porsche's new electric power steering system, it looks similar but less sophisticated to the NSX one! They'll catch up eventually :)

Cheers

Mark

Nick Graves
07-03-2012, 01:45 PM
Indeed; the EPS virtually cuts off once the car is rolling, so it's virtually manual. It's about the only EPS car I've driven with acceptable steering feel. The S2000 is fast-geared, but requires chassis braces in order to have any real sense of impending breakaway. Swapping between the two is a bit weird at first, but one soon adjusts. Actually, the hydraulic on the Civic is quite twirly too. The hydraulic (front) on the Prelude is quick; even more quickened by the electric on the rear and is the most perfect all-round that I've ever used.

Modern cars; might as well get the train.

gumball
07-03-2012, 04:19 PM
No need for power assistance really, especially with my early casters. The steering feel of my car compared to the later car I road tested sold the car to me.

AR
07-03-2012, 05:23 PM
Non PAS is my preference.

havoc
07-03-2012, 07:17 PM
Indeed; the EPS virtually cuts off once the car is rolling, so it's virtually manual. It's about the only EPS car I've driven with acceptable steering feel. The S2000 is fast-geared, but requires chassis braces in order to have any real sense of impending breakaway. Swapping between the two is a bit weird at first, but one soon adjusts. Actually, the hydraulic on the Civic is quite twirly too. The hydraulic (front) on the Prelude is quick; even more quickened by the electric on the rear and is the most perfect all-round that I've ever used.

Modern cars; might as well get the train.
And just to round the fast Hondas off:-
- The DC2 has very good feel and very natural weighting for PAS - less assistance than most cars. Numb immediately around the straight-ahead (the most difficult bit of PAS), but genuinely very good elsewhere.
- The DC5 feels artifically heavy without much 'granularity', but is very direct and responsive.
- The MB-series Civic (Rover-era 5-door) isn't really worth mentioning...


For me, the EPS on the NSX is a bit of a curate's egg - it still takes some getting used to, even after 2.5 years of ownership, and could do with a little more of that 'granularity' I mention above getting through, but then you'd get the kickback that Mark mentions, and you'd probably need to lose some of the castor the NSX was engineered with (which could adversely affect tyre wear*, among other things). Can live with it, and it does suit the character of the car (perhaps it dictates it, a little bit...), but have encountered better systems.


* Assuming you added static camber to compensate for the loss of dynamic camber.

Nick Graves
08-03-2012, 01:59 PM
Kickback isn't really a problem with the NSX (or other Hondas) due to the centre-point steering geometry (hence the big wheel offsets) and also the walking front suspension.

The latter gives some people the walking blues, but I've got used to it.

Although it is the almost total lack of any artificial geometry (only Citroen ever fully got rid of it) that gives the Prelude such stunningly good steering. Of course with the DIRAVI Citroens, there was no steering feel at all. None. B ugger all. But their manual systems were good, if terribly heavy when parking.

markc
08-03-2012, 03:05 PM
Of course with the DIRAVI Citroens, there was no steering feel at all. None. B ugger all.

Allow me to disagree with that on a technicality ;)

There IS feel/feedback but it is entirely artificial. This is what the DIRAVI system, pioneered in the SM, added to Citroen's previous all hydraulic system from the DS etc. Once the hydraulic system pressure is up (takes up to 20 seconds) there is no mechanical connection between the column and the rack at all :eek: The system uses steering angle and road speed, all via hydraulics, to provide the artificial feel/feedback. A well serviced and set-up DIRAVI system is magical and unnerving at the same time... and then you hit the brakes :D

I can't wait to unearth the old CX from it's winter slumber and go for a wobble along a few winding, lumpy country roads :cool:

I'm rather spoiled for great steering as my Racing Puma has one of the best steering systems I've ever encountered (better than a DC2). Could hardly be more different to the Citroen though!!!

Cheers

Mark

Nick Graves
08-03-2012, 05:14 PM
I probably need to try a good one. It was a long time ago in a distant galaxy.

I remember the brakes - heel & toe is virtually impossible, but the system is great when you adjust.