[toxicnerve]

I was under the impression that the PAS in our cars was purely hydraulic but someone was saying that BMW introduced a servo/electrical assistance system.

Does my E92 have this? It was manufactured in December 2008 and first registration was in January 2009.

Cheers.

TN

[themetz]

335d and i are both hydraulic.

other 4/6 cyl are leccy.

introduced with the efficient dynamics palava.

[xenon]

They're all hydraulic in strictest sense, but the on the ed cars the hydraulic pump is electrically driven rather than driven by an engine pulley. It can therefore be switched off 99% of the time when it's not needed.

[SteveC]

Originally Posted by xenon

They're all hydraulic in strictest sense, but the on the ed cars the hydraulic pump is electrically driven rather than driven by an engine pulley. It can therefore be switched off 99% of the time when it's not needed.

Actually EPS has no hydraulic component, purely electro-mechanical

[NFS]

Originally Posted by themetz

335d and i are both hydraulic.

other 4/6 cyl are leccy.

introduced with the efficient dynamics palava.

Terrible decision by BMW.

Oddly enough I believe the 318d also has hydraulic steering.

[themetz]

Originally Posted by NFS

Terrible decision by BMW.

Oddly enough I believe the 318d also has hydraulic steering.

indeed - looks like all diesels stick with the hydraulics (except new 330d!?!?!?) ... can't have been able to integrate it in them mid cycle like they could with the petrols.

[toxicnerve]

So am I correct in saying that my 335d will have a purely hydraulic system which is pulley driven via the engine?

[rup]

well my 57 320d had electronic PAS, think all the ED cars do. My 56 330D has hydraulic which feels much better, or is that the extra 200 torques

[NFS]

You can see exactly which cars have electric steering here (and any other efficient dynamics stuff):

http://bmw.co.uk/bmwuk/efficient_dynamics/bc/standard

The 335i / 335d are the only cars that appear to get the hydraulic system.

But ....

BMW also state hydraulic steering for the auto 4 pot diesels:

http://bmw.co.uk/bmwuk/pricesandspec...%3D%3D,00.html

Plus conflicting info on the 320d's

http://bmw.co.uk/bmwuk/pricesandspec...%3D%3D,00.html

Best to buy a 335i to make sure

[SteveC]

why would hydraulic be better than electric in terms of either weighting or feedback?

I've owned BMWs with both versions and find EPS perfectly weighted in pretty much all situations.

One thing I should mention is that 3 psi in the front tyres has radically more effect than the difference between any version of BMW PS. That's the difference between pumping your tyres cold vs. warm or on a cold vs. warm morning.

At least with BS RFTs a couple of PSI the wrong side of optimal will produce swimmy, unplanted, underweighted steering in fast corners (too hard) or a choppy ride (too soft).

A few degrees difference in air temperature is enough to start feeling the difference and 15-20 degrees difference without adjusting tyres will change the handling of the car, usually for the worse.

Anyone reporting on steering or suspension quality, without first accurately controlling cold tyre pressures is blowing smoke.

The conclusion I've reached is that chassis and steering feedback is good enough to detect even small changes in tyre pressure and given the large swings in handling that minor pressure changes make, its likely that a lot of the feedback attributed to steering and suspension is actually down to maladjusted tyres.

[xenon]

Originally Posted by SteveC

Actually EPS has no hydraulic component, purely electro-mechanical

Fair enough. That explains why it's shit.

[MEGA]

I hate the electric steering/weighting.

My 06 320d which I believe is hydraulic?? Although the links above make me confused? Feel perfect. Love the weight. It feels like a mans car. Same with the gearbox! Top stuff...

I've driven an 09 ed 320d, and a 10 place 116i recently - and in both cases the steering was so light. It didn't feel like I was properly in control of the car. Lacking feedback of ANY kind through the wheel and could be turned on the spot stood still with my little finger. Awful!

[doughboy]

Originally Posted by toxicnerve

So am I correct in saying that my 335d will have a purely hydraulic system which is pulley driven via the engine?

Yes, a 'proper' system, like the 335i.

http://www.realoem.com/bmw/showparts...66&hg=32&fg=15

Leccy systems are solely designed to save fuel first of all, and then the designers have to minimise the negative apsects of it. I'll stick with the 0.1 mpg less.

Don't forget the M3 has pure hydraulic also, as M division couldn't get the leccy one to give the feel and response they needed.

Same as they couldn't get RFTs to work either.

There's a suprise!

[toxicnerve]

SteveC,

I totally agree about monitoring pressures closely as I know from experience how even small changes can affect the handling of the car. For this reason Ido tend to keep my pressures in check but even so I have noticed that sometimes the steering can feel over-assisted, which I do not like one bit. 99% of the time the steering feels heavy but in a good way. I find the weighting allows one to be more precise with steering inputs.

[yatin c]

my wifes 118i has got the electric steering. around town and lower speeds it is too light and feels disconnected, but once you push the car it does weight up quite nicely and provide a lot more feedback - probably not uk legal speeds though (my experience on private roads) - maybe the ratios etc designed for german driving?

would agree with the comments about tyre pressure, i find on both of our cars 0.2bar extra makes them feels very different

yatin

[NFS]

Originally Posted by SteveC

why would hydraulic be better than electric in terms of either weighting or feedback?

I've owned BMWs with both versions and find EPS perfectly weighted in pretty much all situations.

That's odd, because there is a MASSIVE between the EPS and hydraulic systems.

If you drive them 'back to back' this becomes very obvious indeed.

[xenon]

There is no reason why the hydraulic system should feel any different to the electric. It would be possible, one supposes, for the designers to ensure that each provides the same amount of assistance. Furthermore, it could be argued that the electrical system could actually be better as it can dynamically vary the amout of assistance required depending on speed, amount of lock and so on.

Unfortunately they didn't and it's over-assisted shite.

[jhbodle]

Originally Posted by xenon

There is no reason why the hydraulic system should feel any different to the electric. It would be possible, one supposes, for the designers to ensure that each provides the same amount of assistance. Furthermore, it could be argued that the electrical system could actually be better as it can dynamically vary the amout of assistance required depending on speed, amount of lock and so on.

Unfortunately they didn't and it's over-assisted shite.

Well put!

Compared to my 335i, I have tried several ED cars when mines been in for work - an early ED 116i which had terrible steering feel, then a ED 120i which felt a fair bit better and finally spent 2 weeks in an ED 320d recently that felt better still. Got back into my 335i and thought the power assistance had broke - needed so much more effort to turn the wheel. Wouldn't have it any other way though!

Don't BMW make an option that you can specify on the new ED cars for a more meatily-programmed steering feel? I read about it on here somewhere. Does it make any difference?

[ss134]

Originally Posted by SteveC

why would hydraulic be better than electric in terms of either weighting or feedback?

I've owned BMWs with both versions and find EPS perfectly weighted in pretty much all situations.

One thing I should mention is that 3 psi in the front tyres has radically more effect than the difference between any version of BMW PS. That's the difference between pumping your tyres cold vs. warm or on a cold vs. warm morning.

At least with BS RFTs a couple of PSI the wrong side of optimal will produce swimmy, unplanted, underweighted steering in fast corners (too hard) or a choppy ride (too soft).

A few degrees difference in air temperature is enough to start feeling the difference and 15-20 degrees difference without adjusting tyres will change the handling of the car, usually for the worse.

Anyone reporting on steering or suspension quality, without first accurately controlling cold tyre pressures is blowing smoke.

The conclusion I've reached is that chassis and steering feedback is good enough to detect even small changes in tyre pressure and given the large swings in handling that minor pressure changes make, its likely that a lot of the feedback attributed to steering and suspension is actually down to maladjusted tyres.

^Correct - i run 2.2F 2.4 R on my 18s RFT and the car is much more planted than running the reccommended pressures of 2.3/2.7.

I have to check my pressures weekly as the weather does affect the pressures and the difference in handling is very noticable.

[ss134]

Originally Posted by xenon

There is no reason why the hydraulic system should feel any different to the electric. It would be possible, one supposes, for the designers to ensure that each provides the same amount of assistance. Furthermore, it could be argued that the electrical system could actually be better as it can dynamically vary the amout of assistance required depending on speed, amount of lock and so on.

Unfortunately they didn't and it's over-assisted shite.

The reason BMWs electic steering is over assisted is the same reason that they softened up the M Sport suspension on the LCI - they are catering for the vast majority of BMW owners who are not enthusiasts and want a comfortable car that is easy to manouvre at low speeds, parking etc.

Shame for the rest of us but its all about selling more cars unfortunately.

[jhbodle]

Originally Posted by ss134

The reason BMWs electic steering is over assisted is the same reason that they softened up the M Sport suspension on the LCI - they are catering for the vast majority of BMW owners who are not enthusiasts and want a comfortable car that is easy to manouvre at low speeds, parking etc.

Shame for the rest of us but its all about selling more cars unfortunately.

True, but I thought they would have learned their lesson after the E46 debacle when they fitted over-light steering to mid-life models. These cars got dubbed 'The Ultimate Parking Machine' and BMW offered retrofits to improve the steering weight.

[ss134]

Originally Posted by jhbodle

True, but I thought they would have learned their lesson after the E46 debacle when they fitted over-light steering to mid-life models. These cars got dubbed 'The Ultimate Parking Machine' and BMW offered retrofits to improve the steering weight.

IMO BMW are at a crossroads -i drove a friends Z4 35i yesterday and it is noticably softer than the old Z4. I believe they are now focusing on marketing and sales at the expense of driving dynamics and driver focused cars.

If BMW are not careful their hard built reputation of being a sporty manufacturer producing great handling cars will never recover from recent models - even the new 5 series has suffered in the handling department compared to the previous generation although in most other areas i am sure it is a better car.

If BMW continue in this way i can see a lot of long term BMW enthusiasts looking elsewhere for their future cars although BMW probably won't care as for every customer that wants dynamics and handling as a priority there will be 10 new customers who just want image and comfort and would probably not even care if the car was front wheel drive.