Steering issues....might go hydraulic

Southwestz4 · Post by **Southwestz4** » Wed Oct 05, 2022 1:50 pm

Hello everybody
I have been having some issues with my e85 steering ...again !
It gets very 'grabby ' on bad roads ...having to correct it quite a bit and at speed in a straight line it feels a little vague and wanders a bit but is ok in the corners when pushing on .
So far the following have been done....
Michelin ps4s fitted
Eps ring adjusted due to sticky steering
New front and rear shocks/mounts
New front and rear springs
New front lower arms and lollypops ( Melye)
New track rod ends ( Melye )
New anti rollbar bushes ( Powerflex )
New drop links ( Melye)
All 4 wheels roadforce balanced and full Hunter alignment.
Because of this I am looking into the hydraulic conversion...will this sort it ??
Or am I just trying to iron out the sports car characteristics which are simply down to the steering and suspension setup from factory?
Thanks Andy

Southwestz4 · Post by **Southwestz4** » Wed Oct 05, 2022 9:44 pm

Anyone ??

bigwinn · Post by **bigwinn** » Wed Oct 05, 2022 9:48 pm

having driven Johns z4 next door I have to say I will one day do this

it was a different car, much more direct, better feeling and feedback and 'meatier' if that makes sense

its a must do for me as a project in the very near future

Looking at the list of stuff to buy its all very reasonable and not a huge job

Southwestz4 · Post by **Southwestz4** » Wed Oct 05, 2022 9:53 pm

Thanks Stuart
Looks like that's the way to go then, I did a quick tot up of bits ...around £1100 inc a recon purple tag rack and new z4m lower column shaft.
Hopefully money well spent...I am good on the spanners and looks fairly straightforward

Rldee007 · Post by **Rldee007** » Wed Oct 05, 2022 9:57 pm

I was speaking to a owner with Z4M Roadster and Z4 coupe and he told me it is better but not as much as expect. He has had Z4M coup too.

Rldee007 · Post by **Rldee007** » Wed Oct 05, 2022 9:58 pm

I was speaking to a owner with Z4M Roadster and Z4 coupe and he told me it is better but not as much as expect. He has had Z4M coup too. That said I would do it if I have to refresh my steering. It has pretty well documented if you look in the right places.

bigwinn · Post by **bigwinn** » Wed Oct 05, 2022 10:00 pm

Southwestz4 wrote: ↑Wed Oct 05, 2022 9:53 pm Thanks Stuart
Looks like that's the way to go then, I did a quick tot up of bits ...around £1100 inc a recon purple tag rack and new z4m lower column shaft.
Hopefully money well spent...I am good on the spanners and looks fairly straightforward

Let me know- I know we are a few miles away but happy to help in any way

Do a good write up as well!

I can figure it all out apart from the old column set up...

Mr Tidy · Post by **Mr Tidy** » Wed Oct 05, 2022 10:55 pm

I've only had 3 cars with EPAS. The first was a facelift E87 1 Series and it was much better than the set up on either of my 3.0Si Coupes, but then I think the E85/86 cars got BMWs first attempt with EPAS in 2003 whereas my 1 Series was from 2007.

But after getting my MC with HPAS I'd agree completely with "bigwinns" assessment.

Smartbear · Post by **Smartbear** » Thu Oct 06, 2022 4:08 am

Southwestz4 wrote: ↑Wed Oct 05, 2022 1:50 pm Hello everybody
I have been having some issues with my e85 steering ...again !
It gets very 'grabby ' on bad roads ...having to correct it quite a bit and at speed in a straight line it feels a little vague and wanders a bit but is ok in the corners when pushing on .
So far the following have been done....
Michelin ps4s fitted
Eps ring adjusted due to sticky steering
New front and rear shocks/mounts
New front and rear springs
New front lower arms and lollypops ( Melye)
New track rod ends ( Melye )
New anti rollbar bushes ( Powerflex )
New drop links ( Melye)
All 4 wheels roadforce balanced and full Hunter alignment.
Because of this I am looking into the hydraulic conversion...will this sort it ??
Or am I just trying to iron out the sports car characteristics which are simply down to the steering and suspension setup from factory?
Thanks Andy

What tyre pressures are you running since you changed from runflats?
Rob

MKZ4000 · Post by **MKZ4000** » Thu Oct 06, 2022 5:56 am

I know it’s an obvious one but like Smartbear I would be interested to know your tyre pressures.

My first 3.0 I owned suffered from the same symptoms you describe to the point when you got over 60 mph in a straight line it felt dangerous.

By adjusting the tyre pressures made all the difference.

I’ve since had a 2.5 which drove perfectly and also a Z4M which yes does feel better and heavier but not night and day better.

Have you noticed any improvement at all with the changes you have made ?

Southwestz4 · Post by **Southwestz4** » Thu Oct 06, 2022 8:20 am

Smartbear wrote: ↑Thu Oct 06, 2022 4:08 am
Southwestz4 wrote: ↑Wed Oct 05, 2022 1:50 pm Hello everybody
I have been having some issues with my e85 steering ...again !
It gets very 'grabby ' on bad roads ...having to correct it quite a bit and at speed in a straight line it feels a little vague and wanders a bit but is ok in the corners when pushing on .
So far the following have been done....
Michelin ps4s fitted
Eps ring adjusted due to sticky steering
New front and rear shocks/mounts
New front and rear springs
New front lower arms and lollypops ( Melye)
New track rod ends ( Melye )
New anti rollbar bushes ( Powerflex )
New drop links ( Melye)
All 4 wheels roadforce balanced and full Hunter alignment.
Because of this I am looking into the hydraulic conversion...will this sort it ??
Or am I just trying to iron out the sports car characteristics which are simply down to the steering and suspension setup from factory?
Thanks Andy
What tyre pressures are you running since you changed from runflats?
Rob

Hi Rob I'm running 33 f and 36 r

Southwestz4 · Post by **Southwestz4** » Thu Oct 06, 2022 8:27 am

MKZ4000 wrote: ↑Thu Oct 06, 2022 5:56 am I know it’s an obvious one but like Smartbear I would be interested to know your tyre pressures.

My first 3.0 I owned suffered from the same symptoms you describe to the point when you got over 60 mph in a straight line it felt dangerous.

By adjusting the tyre pressures made all the difference.

I’ve since had a 2.5 which drove perfectly and also a Z4M which yes does feel better and heavier but not night and day better.

Have you noticed any improvement at all with the changes you have made ?

Yes it does feel better , less tramlining etc. The car is and 54 plate 3.0 which when I bought it had 68k on it , the front shocks were absolutely done , virtually no rebound on them !
Im wondering if..
1. Maybe I have got too much play in the eps ring after adjusting out the sticky steering or
2. Maybe rear end bushes as worn ...would this be feasible?
Thanks all , Andy

MKZ4000 · Post by **MKZ4000** » Thu Oct 06, 2022 8:32 am

Try lowering your pressures to 32 & 30 and report back. Yours seem too high to me

Southwestz4 · Post by **Southwestz4** » Thu Oct 06, 2022 9:23 am

MKZ4000 wrote: ↑Thu Oct 06, 2022 8:32 am Try lowering your pressures to 32 & 30 and report back. Yours seem too high to me

Thanks...30 front and 32 rear?

Southwestz4 · Post by **Southwestz4** » Thu Oct 06, 2022 9:27 am

bigwinn wrote: ↑Wed Oct 05, 2022 10:00 pm
Southwestz4 wrote: ↑Wed Oct 05, 2022 9:53 pm Thanks Stuart
Looks like that's the way to go then, I did a quick tot up of bits ...around £1100 inc a recon purple tag rack and new z4m lower column shaft.
Hopefully money well spent...I am good on the spanners and looks fairly straightforward

Let me know- I know we are a few miles away but happy to help in any way

Do a good write up as well!

I can figure it all out apart from the old column set up...

Thanks Stuart....which part on the column setup are you unsure about ?

Z4-forum.com

Z4-forum.com