BMW E85 and E86 Wheels and Tyres Thread

Alloy wheels and tyre discussion
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kis
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BMW E85 and E86 Wheels and Tyres Thread

Post by kis » Mon Jul 09, 2018 10:20 am

So I figured it was about time someone did this. I’ve looked into tyres/wheels myself and found many members helpful however much of the information while related wasn’t ever linked together and I’d have to go through various threads to piece the things I wanted together.

So this is definitely not exhaustive, but I hope it will help other members and I will make changes as required to update and keep the thread current. I am not a “wheel guru” I’m simply compiling lots of information together, so lots of detail can be available in a single place. This thread is accurate to the best of my knowledge but may well be missing some details. If there is anything you think is worth adding (or changing) I’m happy to do so, just let me know. Maybe if it’s liked it can become a sticky? :)

Firstly I’ll make a short note about pre facelift and facelift as I’ve referenced it at times through the post. For those unsure or not in the know, then generally speaking a 2002-2005 is a pre facelift and 2006-2009 is a facelift. This may be a little muddy in the middle around 2005 and 2006. If you’re reading this paragraph and it’s all new to you then it would be a good idea to also read the forum FAQ’s. Some pictures may not be working but it’s got some good info link here. Another good quick indication is the rear lights. Conversions can be done however it’s only a minority.
Z4 Pre and Facelift Rear.jpg
Z4 Pre and Facelift Rear.jpg (73.36 KiB) Viewed 1222 times
Source: EuropeanAutoSource as shown in bottom right of picture.

OEM E85 and E86 alloys
What types of wheel are standard OEM supplied for the Z4? What’s their size? What tyre size? What’s the offset?

Style 102
7x16” ET47
225/50/16 square tyre set up

Style 103 – Also sometimes referred to as the daisy shaped alloy.
8x17” ET47
225/45/17 square tyre set up

Style 104
7x16” ET47
225/50/16 square tyre set up

Style 106 – Also sometimes referred to as the turbine shaped alloy.
8x17” ET47
225/45/17 square tyre set up

Style 107
8x18” ET47 – front alloy
225/40/18 – front tyre
8 1/2x18” ET50 – rear alloy
255/35/18 – rear tyre

Style 108
8x18” ET47 – front alloy
225/40/18 – front tyre
8 1/2x18” ET50 – rear alloy
255/35/18 – rear tyre

Style 135 – Also known as MV2’s and an “e46 wheel”.
8x18” ET47 – front alloy
225/40/18 – front tyre
8 1/2x18” ET50 – rear alloy
255/35/18 – rear tyre

Style 202 – The updated version of Style 107 alloys.
8x18” ET47 – front alloy
225/40/18 – front tyre
8 1/2x18” ET50 – rear alloy
255/35/18 – rear tyre

Style 224 – The infamous Z4 M wheel.
8x18” ET42 – front alloy
225/45/18 – front tyre
9x18” ET30 – rear alloy
255/40/18 – rear tyre

Could be missing some styles, if I am then let me know!

Alloy OEM wheel colour across the board, from memory is Titan Silver.

Also worth to mention as they’re immensely popular for the Z4, the CSL’s or CSL rep style wheel. These wheels do work particularly well with the Z4. The original is Style 163 which was fitted to the E46 M3 CSL. If the wheels are genuine they will only fit the Z4 M. Otherwise replica wheels referred to as CSL reps can be found in a multitude of sizes (not just 19” and various different staggered fitments). In terms of non-standard wheel I’d say they are the most popular.

A side note, but fully related is that the pre facelift 3.0i models will happily take a 16” alloy wheel. There is no caliper clearance issue. Now while it’s not normal to run a 16” wheel it may be something you’re doing with a spare set over the winter for example. If you’re on a facelift 3.0si then it will not work, the smallest you can go here is a 17” alloy due to the larger caliper and disc set up.

How to read a tyre?
Ever been curious to know how old your tyre is? What’s the size or speed rating? Is my tyre a runflat or not?
Tyre Sidewall.jpg
Tyre Sidewall.jpg (82.35 KiB) Viewed 1222 times
Firstly take a read of this, Michelin Tyre Markings 101.. Theres no point me saying the same things but worded differently, best read straight from the source!
Want to do some further reading? Michelin do a PDF guide as well, link here.

Runflat is either mentioned somewhere on the sidewall or abbreviated to RSC.

The tyre age will be shown on a tyre after the letters DOT. They will be four numbers all in one go. If they’ve got letters in keep looking slightly further right of the DOT letters. They will be marked with the week of production and the year. For example from the picture above you can't see "DOT" but you can see the four numbers "2115”. This will be the 21st week of 2015. So to put it in perspective, this is April 2015.

Related to tyre reading it’s a good idea to visually inspect tyres for signs of deteriation. While age isn’t necessarily an indication of deteriation, that is the general rule of thumb. The older it is, the more likely it is to be in a sorry state. So how old? Up to 3 years from the date of the tyre production it can still be fit for purpose and sold as new (provided it is new and unused). After the tyre has been fitted generally the rule is about 7 years till you should replace, or if you get down to the wear indicators, whichever comes first. Now the 7 years is just a recommendation. There is no rule, law or MOT regulation which says that just because it is an old tyre it’s not safe or fit for purpose. If however you’ve got signs of cracking on the sidewall or in between the treads, or even gouges taken out of the sidewall, then these may well not be fit for purpose.

When to change tyres? The guide below covers this, it also covers how to read the tread depth and explains the wear indicator.
To note, the rear wheels in particular have an “aggressive” rear camber set up from stock. This means it will wear on the insides much quicker than the outsides.
This is what Michelin say. If in doubt always consult a tyre specialist!

Tyres and sizing
While there is always controversy on preference between tyre brands I think it’s safe to say that for a car with a very sporty bias, premium or mid-range tyres are a must. These are keeping you on the road, so it pays to have some quality rubber to keep you on the road. It also good to know how old your tyre is. If it’s “getting on a bit” then it may be wise not to push yourself right to the limit as your traction may be reduced. Age of tyres and reading a sidewall has been covered previously.

Brands which I’ve found to be forum favourites:
Michelins - PS2, PS3, PS4, MSS.
So long as the tyre is a performance tyre and not an ecoeffiency one for example.
Goodyears - Eagle F1 Asymmetric 2 or Asymmetric 3
Vred - Sessanta / Vortis
Uniroyals – RS3

Seen Avons, Hankook and Falkens mentioned a handful of times too. All depends on your budget!

One thing to mention is that some tyre brands vary wildly in actual fit. For example using stock sizes with Hankook or Falken, the tyres for some reason are particularly narrow. So can leave a stretched appearance, which isn’t always to everyone’s taste.

Different brands
Tyres on the same axel should be the same brand and sub model. For example Goodyear and Asymmetric 3. While this isn’t so much of an issue on other vehicles like a small hatchback, it is important on a Z4. The brands between front and back should really be the same as well. Different tyres will have different properties so having a matching set on all four corners is a good idea. If you’re in a transition period then that’s fine, so long as you’ve got it all in mind once the tyres in question start getting close to the wear indicators.

Running a square setup
If you’re running a square setup then it’s essential that, especially as it’s a rear wheel drive, the tyres with the most tread are put on the rear. It’s also good practice to replace the tyres in sets. You’re not doing yourself any favours if your rear wheels are the same brand but one has 7mm and the other side only has 3mm.

17” Tyre Sizes
If you wanted I’m sure you can change the tyres on a 17” rear to be wider. So the fronts will stay the 225/45/17 and rears could be wider at 255/40/17. If you go down this route you won’t be able to rotate them (should you wish to).

18” Tyre Sizes
Changing tyre sizes is also an option for those with 18” wheels. This could be because of a complex suspension and low spring set up, or simply to save some money on opting for slightly thinner tyres. The fronts can be changed from standard 225/40/18 to 215/40/18 (narrower) or 215/45/18 (narrower and for increased sidewall… comfort). Rear wheels as standard are 255/35/18 and this could be changed to 245/35/18 (narrower) or 245/40/18 (narrower and for increased sidewall… comfort).

The tyre width as standard is quite a lot, you don’t really need the full 255mm. You can happily drop this down to 245. In monetary terms comparing Michelin PS4’s this extra 10mm can cost you approximately £50 (per tyre)! Give or take a few pennies (not pounds) when I checked Blackcircles on the 05/07/2018.

If you do opt for increased sidewall on the fronts or the rears there is always a chance you may experience some rubbing. Lots can affect this such as road conditions, condition / age of suspension, whether you have lowering springs, if you’ve got spacers, etc. etc.

If you’re wanting to use Style 224 alloys then you’ll have to change the front tyre sizes to the narrower 215/45/18 at the very least. Otherwise you may find you’ve got rubbing, especially when on full lock when turning.

To runflat or not?
So the conclusion? No.
Read below if you want to know more, if you’re happy then just take my word for it!

So runflat tyres, sounds pretty cool right? An invincible tyre has its benefits? BMW has fitted runflat tyres to a wide range of its fleet to save on production costs to supply and fit a spare wheel, jack, etc. Not to mention the boot space that isn’t eaten up.
Alloy wheels fitted with runflats are more susceptible to cracking. Fact. More apparent on larger diameter alloys. This is due to the sidewall of the tyre being so hard that the shock of a pot hole or deformation in the road it radiated straight into the alloy of the wheel. In the case of larger diameter alloys this gap is less (due to low profile tyres) so much more of the shock is radiated directly into the alloy wheels metal.
Due to this ridged sidewall, they’re obviously more susceptible to buckling as well.
Runflat tyres cost more than conventional tyres.
Conventional tyres provide a much better ride quality due to the sidewall being much less ridged than that of the runflats.
BMW M vehicles do not have runflats (from factory anyway). Food for thought. M vehicles have a temporary tyre repair kit. If you choose to mirror this setup and have a repair kit then you can get an OEM kit, Holts Tyreweld, Slime Tyre Sealant, or similar.
Some people opt to carry a spare space saver wheel 16” or 17” which fits nicely in the boot. It will take up a sizeable amount of space. With this set up you’ll also have to factor for putting the punctured wheel back in the boot. So if you’ve got an 18” staggered rear wheel to put back in, and your boot is already full… your passenger may not be happy resting it in their lap!

If you do choose to go down a space saver route, which is what I’ve done, you have two main sizes as mentioned earlier in this thread. 16” is normal for a pre facelift and 17” for a facelift. For the pre facelift I’m unsure about sizes for some of the smaller engines, so perhaps you can get away with a 15” space saver with a 2.0i for example. However that being said the 16” wheels are plentiful and well-priced. I have a well reputed source who confirms that any space saver will fit on the Zed. That being said you will still have to be mindful of tyre sizes. You could buy a X3 space saver 135/90/17 thinking you’ve snagged a 17” space saver bargain but they won’t fit as the sidewall is too large. So what do you buy?
16” Space Saver – 115/90/16 approx. £30 for an average condition wheel. Expect to pay more for a mint one with no rust, etc.
17” Space Saver – 125/80/17 or 135/80/17 approx. £60 for an average condition wheel. Expect to pay more for a mint one with no rust, etc.

After writing this I stumbled across this thread. This gives some pictures and further details which may help someone out if moving from the runflats.

Image
Picture taken from PawnSacrifice’s thread above.

What PSI to run?
Lots of factors to consider with this, and there’s no real definite answer. It’s not a black and white answer unfortunately. Use the info below and you can have a play around with it slightly increasing or decreasing to find a pressure that suits you / the car / the road / the tyre.

Firstly there are different recommended pressures between the models. For example the handbook states for the 2.5i its 30F & 33R and the 3.0i its 33F & 36R for use with stock runflat tyres. So keep the stock pressures in mind, you can also find these on the sticker inside the door panel.

Many people use these pressures with their non-runflats. Although I’ve seen the ratio change slightly to 34F & 36R.

The M wheels run a different pressure altogether which is 30F & 32R.

So I would use somewhere between 30 and 34 for the front and 32 and 36 for the rear as a good general starting point.

Under inflation or over inflation also reduces tyre life. If it’s extreme it might be apparent, the centre section of the tread will wear faster if its over inflated. If it’s wearing relatively evenly on both outer edges of the wheel you may have under inflated tyres. With the way the rear tyre is, if you’ve got more wear on the inside edge of the wheel then don’t worry too much this as it’s normal (so long as it’s not excessive). This brings it nicely to the next section, wheel alignment.

Wheel alignment
I’ve been contemplating whether to add this or remove (as technically its neither wheel nor tyre related) and think that I’ve settled with leaving it as read. While not 100% related but it does have its links, and when I set out making this I wanted lots of info in once central place. It is a lot of info so feel free to skip down over the techy bits.

Incorrect wheel alignment will have an adverse effect on handling and also tyre wear. If you’ve not got any paperwork to support a recent alignment it may be wise to get an alignment health check.

Be weary of getting an alignment at the likes of QuickFit, etc. They’ll not be able to offer you a bespoke service and may say some elements cannot be adjusted without going to BMW. Like for example the front camber. The reality is that if the place know what they’re doing, they’ll be able to properly adjust your car. If they don’t, well do you really want them adjusting your car?

To cut a long story short, and if you’re new to the scene then a simple Z4 M alignment set up will hold you in good stead. If then you want to take things further and tweak things, then you can.

Most people want less understeer, which is inherently built into the factory setup. This is particularly apparent on non Z4 M models with so much more rear camber than front.

Front Camber
It’s reasonable to aim for maximum front camber (by pushing the pins all the way in). It will vary from car to car but this usually ends up with similar front camber in the region of 1.5 degrees plus or minus a quarter. You should then try balance the camber left and right back to whatever the lowest common denominator. For example if one goes to 1.5 and the other only goes to 1.3 get both at 1.3.

Front Toe
It's not generally advisable to run toe out on either end on the road as it's a bit too lively and not nice on the motorway with more potential for less straight line stability.

The front can be run at parallel or close to zero without any major adverse effects. It's why I often commented to aim for 0.02-0.05 on both sides.

Rear Camber
Rear camber should be in the region of 1.5 degrees plus or minus a quarter. You should then try balance the camber left and right back to whatever the lowest common denominator. For example if one goes to 1.5 and the other only goes to 1.3 get both at 1.3. You may find the stock adjustment doesn't go that low if the bushes are worn so just take the same approach as the front but aim for minimum rather than maximum camber.
If you’ve made adjustments to the front and rear camber and they end up with similar values at the front and back, keep in mind that it’s better having more camber at the front. So a setup like 1.4 front and 1.3 rear.

Rear Toe
Rear toe is the final factor then and the closer you run it to zero the more lively the rear end will be. Usual suggestion is to run a bit more than front but less than factory if you want a sharper car. With all other parameters set this is the one you could play with to add or remove oversteer to taste. I found it was not overtly lively running low numbers like 0.04-0.06. Again balance the left and right back to the lowest common denominator.

If you aren't aware the measurements are shown in minutes and seconds versus degrees. For example 2o 24 is 2.4 degrees. There's 60 seconds in each minute so 24/60 is 0.4 degrees. The numbers I mention above are in degrees so you're aiming for rear camber that reads something like 1o 15.


Spacers
Spacers will add a better flush look, they will not add any performance gains, grip, etc. This is mostly a cosmetic modification. If you want a flush look it’s either:
12mm on the front and 20mm on the rear
or
15mm on the front and 20mm on the rear

With the 15mm on the front some people report rubbing. These spacers assume you’re running relatively stock wheels and offsets like the 107’s or 108’s with stock or similar set up in suspension.

Spacer construction, you’ll probably want to get hubcentric ones from a fairly well reputed company. If they’re not made well it can mess with handling and the balancing of the wheel. If you’re getting spacers then the existing hub bolts will be too short, so ensure you get longer ones. This goes for locking bolts as well. If you’re buying a kit then make sure they’re supplied. The manufacturer will know how much longer they need to be, what thread, pitch, etc. and can pop them in the same box with the spacers.

Thanks to all the forum for all the previous posts covering these aspects. Special thanks to Steve84N for the majority of the information gathered regarding alignment. And special thanks to MrWilks where most of the information has come, spread over about 5 years’ worth of posts!!
Rare '15 Plate E85 Z4 3.0i SMG

BMW Family History (past and present):
1 Series - E87
3 Series - E46 320ci, E46 M3, E90 (x2)
4 Series - F36, F82 M4
5 Series - E34 (x2), E39
X5 - E53, E70
X6 - E71
7 Series - E32

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BMW E85 and E86 Wheels and Tyres Thread

Post by Minion3 » Mon Jul 09, 2018 8:15 pm

Great article, perfect timing as looking to change from runflats. Intend to keep 108s As love look. Any info on the tyre pressure sensors when changing from RSC?
:thumbsup:
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BMW E85 and E86 Wheels and Tyres Thread

Post by kis » Mon Jul 09, 2018 8:30 pm

No issues with the sensor, changing from runflats won’t effect it. Just get tyres replaced in the usual fashion... :)
Rare '15 Plate E85 Z4 3.0i SMG

BMW Family History (past and present):
1 Series - E87
3 Series - E46 320ci, E46 M3, E90 (x2)
4 Series - F36, F82 M4
5 Series - E34 (x2), E39
X5 - E53, E70
X6 - E71
7 Series - E32

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BMW E85 and E86 Wheels and Tyres Thread

Post by Montegojones41 » Tue Jul 17, 2018 9:05 pm

Really useful information thankyou!
New owner still finding out new things ,especially if i want change type of alloys , recently went from runflats to uniroyal rainsports :-)
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BMW E85 and E86 Wheels and Tyres Thread

Post by mr wilks » Tue Jul 17, 2018 9:07 pm

A concise read for anyone unsure & applause to kis for his time & effort putting it down , should be a sticky in this section as there are so many members who ask questions that are answered above
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BMW E85 and E86 Wheels and Tyres Thread

Post by philbo909 » Tue Jul 17, 2018 10:45 pm

Well done for putting that together, lots of info for anyone unsure on wheel set ups, should get stickied :thumbsup:
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BMW E85 and E86 Wheels and Tyres Thread

Post by Z4C_er » Wed Jul 18, 2018 10:10 am

Great, informative thread. Well done kis! :happyclap: :bow:
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BMW E85 and E86 Wheels and Tyres Thread

Post by kis » Wed Jul 18, 2018 3:05 pm

Thanks for the comments guys 8)

As mentioned it was something I felt would be really useful, and you'd often see different members asking the same/similar questions only days apart. Also some of the things I've mentioned I only stumbled across by chance, so unless you're looking for it, could be hard to find out. The forums been great for me, so nice to give something back! Even if it did take a while to put together :rofl:
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BMW Family History (past and present):
1 Series - E87
3 Series - E46 320ci, E46 M3, E90 (x2)
4 Series - F36, F82 M4
5 Series - E34 (x2), E39
X5 - E53, E70
X6 - E71
7 Series - E32

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BMW E85 and E86 Wheels and Tyres Thread

Post by Ewazix » Thu Jul 19, 2018 7:46 am

Great info all in one place, thanks Kis and the sources.

Bookmarked :thumbsup:
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BMW E85 and E86 Wheels and Tyres Thread

Post by PeterZed » Thu Jul 19, 2018 9:28 am

Thanks for this as I am about to change my wheel /tyre setup :driving: :thumbsup:
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BMW E85 and E86 Wheels and Tyres Thread

Post by C8H18 » Thu Jul 19, 2018 10:21 pm

Great guide. But...
kis wrote:
Mon Jul 09, 2018 10:20 am

Spacers
Spacers will add a better flush look, they will not add any performance gains, grip, etc.
Not quite. Spacers increase track. This, in turn, decreases lateral weight transfer when cornering. The performance gains are similar to that of lowering the cars centre of mass by fitting lowering springs. There's a reason why performance cars have wheels right in the corners with flared arches.
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BMW E85 and E86 Wheels and Tyres Thread

Post by marty4 » Sun Jul 22, 2018 3:32 pm

Thanks for the great post. Sadly z4 no longer with me, gone to M135 instead...different sort of fun!

I’m needing new front tyres, same size as old zed on 225x40x18 run flats. Main dealer wants £240 each, wondered if anyone had found any good deals around London area? Michelin on the rear, any thoughts on mixing?
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BMW E85 and E86 Wheels and Tyres Thread

Post by kis » Sun Jul 22, 2018 7:23 pm

C8H18 wrote:
Thu Jul 19, 2018 10:21 pm
Great guide. But...
kis wrote:
Mon Jul 09, 2018 10:20 am

Spacers
Spacers will add a better flush look, they will not add any performance gains, grip, etc.
Not quite. Spacers increase track. This, in turn, decreases lateral weight transfer when cornering. The performance gains are similar to that of lowering the cars centre of mass by fitting lowering springs. There's a reason why performance cars have wheels right in the corners with flared arches.
Hi thanks for your comment.

I’ve never heard of performance cars having spacers? If they’re designed to have a wide wheel base then fine but not sure I’ve ever heard of anyone stick spacers on any car for performance gains? We’re taking about a road car after all?

Could very easily be wrong! Not done enough research into it to be honest. If you’ve got articles to indicate otherwise I’d be happy to change it on the thread. Also would adding spacers really quantify noticeable gains? Surely that would only be noticing on track environment?
Rare '15 Plate E85 Z4 3.0i SMG

BMW Family History (past and present):
1 Series - E87
3 Series - E46 320ci, E46 M3, E90 (x2)
4 Series - F36, F82 M4
5 Series - E34 (x2), E39
X5 - E53, E70
X6 - E71
7 Series - E32

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BMW E85 and E86 Wheels and Tyres Thread

Post by kis » Sun Jul 22, 2018 7:33 pm

marty4 wrote:
Sun Jul 22, 2018 3:32 pm
Thanks for the great post. Sadly z4 no longer with me, gone to M135 instead...different sort of fun!

I’m needing new front tyres, same size as old zed on 225x40x18 run flats. Main dealer wants £240 each, wondered if anyone had found any good deals around London area? Michelin on the rear, any thoughts on mixing?
Mixing? It’s best not to. Tyres have different properties so you may find yourself in a situation where your front tyres (for example) are more grippy in certain conditions than your rears. Let’s say it’s raining and front axel has better traction and water dispersion than another... not really ideal!

Plus if they’re matching it’s better aesthetics :wink:
Rare '15 Plate E85 Z4 3.0i SMG

BMW Family History (past and present):
1 Series - E87
3 Series - E46 320ci, E46 M3, E90 (x2)
4 Series - F36, F82 M4
5 Series - E34 (x2), E39
X5 - E53, E70
X6 - E71
7 Series - E32

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BMW E85 and E86 Wheels and Tyres Thread

Post by C8H18 » Wed Jul 25, 2018 10:25 pm

kis wrote:
Sun Jul 22, 2018 7:23 pm
C8H18 wrote:
Thu Jul 19, 2018 10:21 pm
Great guide. But...
kis wrote:
Mon Jul 09, 2018 10:20 am

Spacers
Spacers will add a better flush look, they will not add any performance gains, grip, etc.
Not quite. Spacers increase track. This, in turn, decreases lateral weight transfer when cornering. The performance gains are similar to that of lowering the cars centre of mass by fitting lowering springs. There's a reason why performance cars have wheels right in the corners with flared arches.
Hi thanks for your comment.

I’ve never heard of performance cars having spacers? If they’re designed to have a wide wheel base then fine but not sure I’ve ever heard of anyone stick spacers on any car for performance gains? We’re taking about a road car after all?

Could very easily be wrong! Not done enough research into it to be honest. If you’ve got articles to indicate otherwise I’d be happy to change it on the thread. Also would adding spacers really quantify noticeable gains? Surely that would only be noticing on track environment?
Apologies - I wasn't talking about high performance cars being fitted with spacers, but the performance benefit from increased track. Performance cars don't come with spacers from the factory as the suspension is already configured to perform optimally without them. However, they will likely strive to increase track as much as reasonably practicable due to the performance benefits of doing so.

Would a slight increase in track (from fitting spacers) offer a noticeable performance benefit? Unlikely. There are also downsides, such as increased loads on wheel bearings. I wouldn't use them except to correct a different wheel offset back to OE spec.

I'm probably sounding like a total pedant now. That wasn't my intention - your post was really informative. However, it may be of interest to some people. Equally, if you or the mods think it's an unnecessary distraction on this thread, then I have no objections to the posts being removed. This bloke explains it all much better than I could...

https://m.youtube.com/watch?v=hWijfooeSyU#
2006 silver / muddy 3.0si roadster manual

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