Better handling- where to start?

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Warrior
Joined: Tue 11 May, 2010 11:02
Posts: 382

  Z3 roadster 3.0i

Better handling- where to start?

Post by Warrior » Sun 31 Jul, 2016 00:05

Having only ever driven my own Z3, barring 10 minutes in my brothers 3 years ago, I don't actually know whether I need to make any mods or not but where to start if I want to improve the handling?

I ask as I feel much surer going at higher speeds in the wife's new Tiguan and even my old Citroen van. Might be me, might be because i'm closer to the road but I feel much happier hanging on to the wheel tightly with both hands, even at 69mph - cos obviously I don't go faster :wink: (Seriously 70 andthe occasional bit is my limit) Hate to think what i'd be like at the suggested 140 plus limit!

For info: Tyres new all round - Falkens which eliminated tramlining. Pressures checked regularly.

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Southernboy
Joined: Thu 07 Oct, 2010 13:39
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  Z3 roadster 3.0i
Location: Johannesburg

Re: Better handling- where to start?

Post by Southernboy » Sun 31 Jul, 2016 07:21

First off, check the condition of all 4 shocks, then front strut brace in the engine bay will help lots on the cornering feel. If your concern is lateral stability at higher speed, perhaps you should have the wheel alignment checked at a reputable outlet. Also, do a thorough under car check of all the steering arm and suspension joints. Worn bushes will create a feeling of "looseness". Fitting a rear strut and side struts is hugely expensive, and unless you're planning on being on the grid at Silverstone, don't waste your money. Also, fitting a large wing to the boot makes no difference, so don't go there - the weight of the wing will have more benefit than aerodynamic down force... :lol:

NO, NO, NO...... If you look at the angle of the wing to the horizontal plane, this wing is more likely to provide uplift....

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"Normal is overrated"
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Z3 Upgrades and Additions

mrscalex
Joined: Fri 13 Mar, 2015 09:14
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  Z3 roadster 1.9

Re: Better handling- where to start?

Post by mrscalex » Sun 31 Jul, 2016 07:45

Warrior doesn't sound like a speed/mod freak. So main thing will be looking for where the wear is that's causing the sloppiness to return the car to factory handling.

Southernboy's suggestions seem very sensible to me. The rear shocks inparticular sound like the place to start.

The OEM is Sachs for the struts as I understand. BMW supplied will be very expensive and I've found finding the correct units via 3rd parties a challenge. In my case that's exaggerated by an ignorance on the part of suppliers of the existence of different parts for the Sport version. In the end I decided this was the most reliable source of information and looked for the model number from there. These are 2.2 Sport fronts but will give you the site.

http://www.bavauto.com/shop.asp?HC1=0&h ... M=Z3%203.0
ImageImage
1999 Z3 1.9 Boston Green (Dimitri) - My brother's car owned from new and restored by me
2001 Z3 2.2 Topaz Blue (Trudy) - My car rebuilt from a write-off
2002 Z3 2.2 Titan Silver (Okus) - Project car waiting for a new engine
2001 Z3 2.2 Topaz Blue (Debra) - Donor car/breaker
1998 Z3 1.9 Boston Green (Allsworth) - Donor car/breaker now gone to Z3 heaven
Always happy to try and help with spares :)

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Koolflyer
Joined: Fri 05 Jul, 2013 16:51
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  Z3 roadster 2.8

Re: Better handling- where to start?

Post by Koolflyer » Sun 31 Jul, 2016 09:28

I too have tried to put my 130k 2.8 back to factory condition, but never going to get it as surefooted as my E91 because it's two generations newer in technology. However, over the last three years I've changed the tyres, control arms, drop links, bushes, top mounts, shocks(which all four were dead) and obviously balanced and tracked the steering. Apart from the springs (which looked ok) and the steering rack (which is fine) everything else is new. As I said it's still lively to drive but perhaps that's as good as I'll get, plus to drive it is half the enjoyment.
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1997 Z3 2.8 (M52) Roadster Montreal blue
2013 330d (F31) M Sport Alpine White

srichards
Joined: Sun 11 Oct, 2015 09:24
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  Z3 roadster 2.8

Re: Better handling- where to start?

Post by srichards » Sun 31 Jul, 2016 10:07

They were criticised when new for how they handled. On bumpy roads they weren't much good.

I started with the front and it made little difference. I think if starting again I'd do all the rear bushes and rear suspension. The rear can't be adjusted properly so whatever bushes you use it sets up how the suspension geometry is. I don't think it works as it is. I have another semi trailing arm rear car and it's absolutely sure footed compared to the Z3 so I'd think if you tweaked how the rear was done somehow you could make it better.

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Southernboy
Joined: Thu 07 Oct, 2010 13:39
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  Z3 roadster 3.0i
Location: Johannesburg

Re: Better handling- where to start?

Post by Southernboy » Sun 31 Jul, 2016 10:13

I think the fundamental problem is the width x the length of the wheelbase. It's just a little too "square"... if the length had been another 500+ mm longer, it would have behaved better.
"Normal is overrated"
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Del
Joined: Sat 19 Nov, 2011 18:35
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  Z3 roadster 1.9

Re: Better handling- where to start?

Post by Del » Sun 31 Jul, 2016 10:20

Mine (just a humble 1.9) gradually improved as I gradually renewed virtually everything underneath the car. Shock absorbers, all 4 shock top mounts, front control arms, all bushes, drop-links, track rods and coil springs - over a couple of years. It now feels fairly sure-footed which is what you want from a sports car.

In answer to the question "where to start", I would start with all 4 shock absorbers and renew all 4 top mounts (including the front ones) at the same time. I would also replace the bush on the front lower control arms (assuming the arms are old) and possibly suggest a poly one by Powerflex - a cheap and relatively easy job.

Warrior
Joined: Tue 11 May, 2010 11:02
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  Z3 roadster 3.0i

Re: Better handling- where to start?

Post by Warrior » Sun 31 Jul, 2016 23:02

Thanks all. I've only done 43,000 mile.

Would the shocks be shot so early?

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stevov
Joined: Sun 21 Dec, 2014 15:56
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  Z3 roadster 2.0
Contact:

Re: Better handling- where to start?

Post by stevov » Tue 02 Aug, 2016 07:56

Milage is only part of the issue. Your shocks are at least 13 years old if not more if original. To many of these cars are weekend toys. Sometimes the single biggest factor to enjoying a car is seat time. Spend all week driving a dead feeling neutral handling barge and then expect to jump in something that requires you to drive it once every 2,3 or 4 weeks. Also because it's driven so little the time invested in understanding the handling characteristics and spending the money to improve them is not often done. Ride heights, spring rates, wheel offsets, tyre choice, wheel size, geometry, bush selection, again seat time, everyone's backside tells them different things, track days, performance driving tuition. All some or none may be applicable to any who read this but enjoyment comes as a result of time invested is what I have found over the years. Took a year of daily driving and changes and adjustments to get happy with my z but is now very sweet on Scottish b roads. Feel free to ring me if you have any questions. Mobile Number is on my website..

Warrior
Joined: Tue 11 May, 2010 11:02
Posts: 382

  Z3 roadster 3.0i

Re: Better handling- where to start?

Post by Warrior » Tue 02 Aug, 2016 12:58

Cheers, as per other thread 'Whine when on full lock' on further investigation I was nearly out of power steering fluid so possible steering rack leak, bushes....who knows. Being looked at tomorrow.......and see what needs sorting.

Need to spend some money. She's a low mileage 3.0i and want to get her up to £17k like the one sold at Sytners the other week :wink: :D

mrscalex
Joined: Fri 13 Mar, 2015 09:14
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  Z3 roadster 1.9

Re: Better handling- where to start?

Post by mrscalex » Tue 02 Aug, 2016 13:09

Did the Sytner one sell then? I thought they'd just removed it from sale?
ImageImage
1999 Z3 1.9 Boston Green (Dimitri) - My brother's car owned from new and restored by me
2001 Z3 2.2 Topaz Blue (Trudy) - My car rebuilt from a write-off
2002 Z3 2.2 Titan Silver (Okus) - Project car waiting for a new engine
2001 Z3 2.2 Topaz Blue (Debra) - Donor car/breaker
1998 Z3 1.9 Boston Green (Allsworth) - Donor car/breaker now gone to Z3 heaven
Always happy to try and help with spares :)

Warrior
Joined: Tue 11 May, 2010 11:02
Posts: 382

  Z3 roadster 3.0i

Re: Better handling- where to start?

Post by Warrior » Tue 02 Aug, 2016 16:21

Don't know. Just assumed it had gone........

I'll settle for £16k, or £15,995 and a Mars Bar;)

Del
Joined: Sat 19 Nov, 2011 18:35
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  Z3 roadster 1.9

Re: Better handling- where to start?

Post by Del » Tue 02 Aug, 2016 19:49

Little 2 seater, soft top, sports cars generally age very well and the Z3 is no exception. I find, as it carries the German BMW badge and is relatively uncommon, that it tends to punch above its weight and generally gets remarks of admiration.

The handling and ride are very important parts of the driving experience for a sports car.

In my view your 3.0 example, with very low mileage, is a particularly desirable model and well worth investing some money on refreshing the suspension to your taste.

In my experience rubber components deteriorate with age as much as they do with wear which could affect seals in the shock absorbers and bushes etc.

http://www.zroadster.net/forum/viewtopi ... +absorbers

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lightning
Joined: Tue 27 Nov, 2007 08:15
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  Z3 roadster 3.0i
Location: Stockport

Re: Better handling- where to start?

Post by lightning » Tue 02 Aug, 2016 22:14

Well, my 2002 3.0 drives really well with none of the issues mentioned above.

The car has done 56,000 miles and is in mint condition with no rust underneath on any parts. But it still has 56,000 miles.
It is the Sport version so l don't know how much better that is.
I had a 2.8 a few years ago and that was a lot softer.

But my 3.0 is very impressive, and my last car was an Elise S2 so l know what a great handling car feels like.
The Z3 has four new tyres but the rest of it looks original.

Del
Joined: Sat 19 Nov, 2011 18:35
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  Z3 roadster 1.9

Re: Better handling- where to start?

Post by Del » Tue 02 Aug, 2016 22:36

lightning wrote:It is the Sport version so l don't know how much better that is.
From what I've been able to find out, the BMW OE Sport option suspension was around 15mm lower and used an up-rated Sachs shock absorber (which is now no longer available in aftermarket form). Also, front ARB 25.5mm thick (standard 25mm) and rear ARB 16mm (standard 15mm). :D :rtm:

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lightning
Joined: Tue 27 Nov, 2007 08:15
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  Z3 roadster 3.0i
Location: Stockport

Re: Better handling- where to start?

Post by lightning » Wed 03 Aug, 2016 10:01

So if l ever need new shocks, what do l fit?

Del
Joined: Sat 19 Nov, 2011 18:35
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  Z3 roadster 1.9

Re: Better handling- where to start?

Post by Del » Wed 03 Aug, 2016 13:53

As far as I could find out, the OE BMW “sport” suspension included the Sachs Advantage shock absorbers which are no longer made by Sachs. The standard Sachs shock absorbers which are widely available are Sachs Super Touring – which I have on my car. There is a mass of debate on online forums about how “sport” owners get new coil springs and shock absorbers. The options seem to be 1) buy from BMW or 2) take a compromise view and fit aftermarket standard stuff all round or more expensive uprated.

mrscalex
Joined: Fri 13 Mar, 2015 09:14
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  Z3 roadster 1.9

Re: Better handling- where to start?

Post by mrscalex » Wed 03 Aug, 2016 13:59

lightning wrote:So if l ever need new shocks, what do l fit?
As per previous post I spent a long time looking into this for a 2.2 Sport. I am pretty convinced this is the correct OEM part for the fronts (listed as 2.5/3.0 as it's US). I guess you can fish around on the site for the rears. When you pick the part numbers up from the page just look on this side of the pond as they are available for as little as £70-£80 ea which I think is okay. The thing is you're best off identifying the part yourself and searching on the part number. Don't rely on the look up tool by model on web sites.

http://www.bavauto.com/shop.asp?HC1=0&h ... M=Z3%203.0
ImageImage
1999 Z3 1.9 Boston Green (Dimitri) - My brother's car owned from new and restored by me
2001 Z3 2.2 Topaz Blue (Trudy) - My car rebuilt from a write-off
2002 Z3 2.2 Titan Silver (Okus) - Project car waiting for a new engine
2001 Z3 2.2 Topaz Blue (Debra) - Donor car/breaker
1998 Z3 1.9 Boston Green (Allsworth) - Donor car/breaker now gone to Z3 heaven
Always happy to try and help with spares :)

Warrior
Joined: Tue 11 May, 2010 11:02
Posts: 382

  Z3 roadster 3.0i

Re: Better handling- where to start?

Post by Warrior » Fri 05 Aug, 2016 02:07

Update.....

Steering Rack is leaking so have a new one on the way. One bush ok, the other not so good so replacing both. Shockers seem fine.

Here's the embarrassing bit........... :oops:

Last year I had the wheels refurbed and dropped off 4 new Falkens to be put on. Looked great, drove fine......although ive really not done many miles at all since.

Yesterday I found out......the bloody wheel nuts were loose...LOL! I always check wheel nuts after a few days when I get a new tyre on my van but I guess I didn't do the same on Zeddie.

Not sure if or how much this would have affected handling but all nuts would take a bit of a turn, the front right taking nigh on a full revolution on at least 2, slightly less on the others.
Last edited by Warrior on Fri 05 Aug, 2016 22:47, edited 1 time in total.

deni2s
Joined: Mon 25 Mar, 2013 22:02
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  Z3 roadster 2.8

Re: Better handling- where to start?

Post by deni2s » Fri 05 Aug, 2016 09:38

I would do poly bushes everywhere (apart from diff bush - keep it OEM or you might feel vibrations on neutral) and add front strut brace (easy and not expensive mod).

Regarding aero - stock car lifts front up on higher speeds, making it less grounded, so no need for rear wing, but some lip on front would help. Probably the best option is Rieger front lip, which looks good and is the only aftermarket lip which is made from ABS. After changing stock bumper to lower CarLine Tuning bumper my car felt much better grounded on fast speeds than before.

I think another important factor for better handling and more fun are wheels - aligning castor and toe might help. Also lighter wheels would help a lot.

Migou
Joined: Wed 24 Jun, 2015 04:09
Posts: 15

  Z3 roadster 2.5i

Re: Better handling- where to start?

Post by Migou » Thu 25 Aug, 2016 04:24

Please don't take offense to this. Most sports cars are better than their drivers.

Replace any items that are worn. Drive and enjoy.

Warrior
Joined: Tue 11 May, 2010 11:02
Posts: 382

  Z3 roadster 3.0i

Re: Better handling- where to start?

Post by Warrior » Tue 18 Oct, 2016 01:50

UPDATE: Rack and Bushes replaced yesterday.

Initial feeling is that feels a lot better but only drove 3 miles home and on the way 2 warning lights popped up Brakes and DSC!!

Thought it may be an air lock clearing in the fluid reservoir but top up not needed. Being looked at tomorrow.


Booked in for tracking on Wednesday. Full report afterwards

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pingu
Joined: Fri 30 Apr, 2004 17:01
Posts: 3337

  M roadster S50

Re: Better handling- where to start?

Post by pingu » Tue 18 Oct, 2016 10:16

Migou wrote:Please don't take offense to this. Most sports cars are better than their drivers.

Replace any items that are worn. Drive and enjoy.
Exactly this. A sorted standard car has been designed by experts.
Pingu

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Brian H
Joined: Tue 16 Dec, 2008 19:55
Posts: 2503

  Z3 roadster 3.0i

Re: Better handling- where to start?

Post by Brian H » Tue 18 Oct, 2016 23:02

stevov wrote:Milage is only part of the issue. Your shocks are at least 13 years old if not more if original. To many of these cars are weekend toys. Sometimes the single biggest factor to enjoying a car is seat time. Spend all week driving a dead feeling neutral handling barge and then expect to jump in something that requires you to drive it once every 2,3 or 4 weeks. Also because it's driven so little the time invested in understanding the handling characteristics and spending the money to improve them is not often done. Ride heights, spring rates, wheel offsets, tyre choice, wheel size, geometry, bush selection, again seat time, everyone's backside tells them different things, track days, performance driving tuition. All some or none may be applicable to any who read this but enjoyment comes as a result of time invested is what I have found over the years. Took a year of daily driving and changes and adjustments to get happy with my z but is now very sweet on Scottish b roads. Feel free to ring me if you have any questions. Mobile Number is on my website..
+1.....A whole lot of sense right here :thumb:

deni2s
Joined: Mon 25 Mar, 2013 22:02
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  Z3 roadster 2.8

Re: Better handling- where to start?

Post by deni2s » Wed 19 Oct, 2016 11:51

pingu wrote:
Migou wrote:Please don't take offense to this. Most sports cars are better than their drivers.

Replace any items that are worn. Drive and enjoy.
Exactly this. A sorted standard car has been designed by experts.
Only that it has been designed many many years ago. I know a guy who spent around 2 years replacing everything on his z3 with brand new oem parts (spent a fortune) and wasn't listening to everyone who advised to use at least poly bushes. After he finished his project he realized that car still don't drive good enough by modern expectations and replaced bushes and shocks to upgraded ones - he liked the result much more.

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pingu
Joined: Fri 30 Apr, 2004 17:01
Posts: 3337

  M roadster S50

Re: Better handling- where to start?

Post by pingu » Wed 19 Oct, 2016 17:55

deni2s wrote:
pingu wrote:
Migou wrote:Please don't take offense to this. Most sports cars are better than their drivers.

Replace any items that are worn. Drive and enjoy.
Exactly this. A sorted standard car has been designed by experts. - to a budget
Only that it has been designed many many years ago. I know a guy who spent around 2 years replacing everything on his z3 with brand new oem parts (spent a fortune) and wasn't listening to everyone who advised to use at least poly bushes. After he finished his project he realized that car still don't drive good enough by modern expectations and replaced bushes and shocks to upgraded ones - he liked the result much more.
I added a bit in bold to my quote :wink: .

It is true that anything can be "improved", but the question to answer is "what is the downside?".

Handling for the track would be rock hard and almost undriveable on the road.

Handling for a bumpy B-road would be too soft for the track.

Poly bushes are excellent when the shaft they are supporting moves either torsionally or axially. If the movement is radial, the poly bush is unlikely to absorb enough energy to protect the surrounding structure and the failure mode will move from the sacrificial rubber mounting to somewhere else.

The same goes for fitting springs and dampers that are too hard. The springs and dampers will survive the harsh bumps, but the suspension turrets and the supporting "legs" may not.

The same goes for low profile tyres. The tyres may survive the potholes, but the wheels may not. I've had to weld one rim on my 330 and another is very slightly buckled - probably because there was not enough sidewall compression to absorb the energy of hitting a pothole.

Re it being designed many moons ago. That is a very true fact. The rear suspension is from the late 70s (introduced in E30 in 1982) and the front suspension is from the late 80s (introduced in E36 in 1990) , but you are stuck with it.

In short, what makes for good handling in one environment may cause problems elsewhere - just be aware.
Pingu

Warrior
Joined: Tue 11 May, 2010 11:02
Posts: 382

  Z3 roadster 3.0i

Re: Better handling- where to start?

Post by Warrior » Wed 19 Oct, 2016 23:21

New rack, new bushes and tracking done today.

Short 15 minute drive home and initial thoughts are good improvement. Could drive with one hand on the wheel, something that didn't always feel possible. Need to try along a particular bit of road which is a narrow dual carriageway with some cambers and ups and downs before approving.

Bonzo
Joined: Wed 21 Mar, 2012 21:52
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  Z3 roadster 2.8
Location: Norfolk

Re: Better handling- where to start?

Post by Bonzo » Thu 20 Oct, 2016 00:52

I wanted a compromise. I wanted Zelda to be reasonably comfortable for long journeys, but to be a little more taut and stable during spirited driving on the twisty bits.
After much researching and posting on the forum I decided to go this route. New Sachs oem springs and shocks all round, new top mounts all round. new ARB mounting bushes front and rear, new drop links all round. (other bushes okay) I fitted a front strut brace. I then had a test drive and she felt much more taut, stable and settled.
I then fitted a Strong Strut Butt Strut and longitudinal body braces and took her out again. I felt there was a small, but definite increase in cornering speed before the back started to slip, and it all seemed to feel more 'together' and less 'jittery'. The comfort was still there, so all in all, to me, this was the right way to go and I am very pleased with the result.

:cheers

Bonzo.
Z3lda (Zelda), 1998 2.8, Montreal Blue, Beige Oregon leather interior and M steering wheel, Sports Seats, Wood trim, Chrome Line Interior, Centre armrest with Cupholder, Alpina Softline wheels, Chromed Angel Eyes, De- tango'd, Rear stone guards, Sport aerial, ASC front strut brace, Strong Strut Butt Strut and Body Brace, Uprated brake fluid, Yellowstuff pads 78k.

Bonzo
Joined: Wed 21 Mar, 2012 21:52
Posts: 864

  Z3 roadster 2.8
Location: Norfolk

Re: Better handling- where to start?

Post by Bonzo » Thu 20 Oct, 2016 00:53

I wanted a compromise. I wanted Zelda to be reasonably comfortable for long journeys, but to be a little more taut and stable during spirited driving on the twisty bits.
After much researching and posting on the forum I decided to go this route. New Sachs oem springs and shocks all round, new top mounts all round. new ARB mounting bushes front and rear, new drop links all round. (other bushes okay) I fitted a front strut brace. I then had a test drive and she felt much more taut, stable and settled.
I then fitted a Strong Strut Butt Strut and longitudinal body braces and took her out again. I felt there was a small, but definite increase in cornering speed before the back started to slip, and it all seemed to feel more 'together' and less 'jittery'. The comfort was still there, so all in all, to me, this was the right way to go and I am very pleased with the result.

:cheers

Bonzo.
Z3lda (Zelda), 1998 2.8, Montreal Blue, Beige Oregon leather interior and M steering wheel, Sports Seats, Wood trim, Chrome Line Interior, Centre armrest with Cupholder, Alpina Softline wheels, Chromed Angel Eyes, De- tango'd, Rear stone guards, Sport aerial, ASC front strut brace, Strong Strut Butt Strut and Body Brace, Uprated brake fluid, Yellowstuff pads 78k.

Bonzo
Joined: Wed 21 Mar, 2012 21:52
Posts: 864

  Z3 roadster 2.8
Location: Norfolk

Re: Better handling- where to start?

Post by Bonzo » Thu 20 Oct, 2016 01:00

Sorry, but I don't know why my last post is duplicated. :head:

:cheers
Z3lda (Zelda), 1998 2.8, Montreal Blue, Beige Oregon leather interior and M steering wheel, Sports Seats, Wood trim, Chrome Line Interior, Centre armrest with Cupholder, Alpina Softline wheels, Chromed Angel Eyes, De- tango'd, Rear stone guards, Sport aerial, ASC front strut brace, Strong Strut Butt Strut and Body Brace, Uprated brake fluid, Yellowstuff pads 78k.

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