Z4 M Coupe Suspension

[R60BBA]

Great feedback thanks.
During my thinking towards modifying the suspension, I'd decided that having flexibility of ride height, and damper settings, even for road use was highly desirable.
Then I saw the price of KW V3...about 3x the B12 kit.

So currently planning on keeping suspension OEM.

Any Ohlins options that people have seen used?

You can’t really compare V3s to the Bilstein B12 kit mate.

I’d say a more fair comparison to the V3s is the Bilstein B16 kit.

But tbh, you don’t need V3s, V2s will do the job (and are not much more than the Bilstein B12 kit).

Plus the main benefit of KW V2s over any Bilstein kit is that they are made from Inox and are thus much more resistant to corrosion. There’s a reason why KW are partners with BMW Motorsport and Porsche.

[AndyBeech]

There is no V2 kit for the Z4M to my knowledge. I’ve been looking for the same and it’s V3’s or clubsports.

[Audidude]

You can’t really compare V3s to the Bilstein B12 kit mate.

I wasn't suggesting you could, the V3s are obviously in a different league, and provide completely different functionality.

The point I was making was that B12s don't have the flexibility I'd want in a suspension modification, and the cost of V3s rule them out for the use to which I put my car. Hence my decision to not modify.

It's one of 4 modern classics I own, and doesn't get the amount of use to justify that expenditure, particularly because as a collectible, which they will become, originality, even if flawed, is a huge plus.

If it was my daily driver, or a track weapon, that would give a very different brief.

[Oh4show]

I went from oem m sport set up to fully adjustable damping and ride height on my e86 lowered 35 mil running the softest setup and my z is like a new car and handles alot better than oem with no understeer and no crashing over bumps , smooth as

[R60BBA]

You can’t really compare V3s to the Bilstein B12 kit mate.

I wasn't suggesting you could, the V3s are obviously in a different league, and provide completely different functionality.

The point I was making was that B12s don't have the flexibility I'd want in a suspension modification, and the cost of V3s rule them out for the use to which I put my car. Hence my decision to not modify.

It's one of 4 modern classics I own, and doesn't get the amount of use to justify that expenditure, particularly because as a collectible, which they will become, originality, even if flawed, is a huge plus.

If it was my daily driver, or a track weapon, that would give a very different brief.

Even if it’s an investment, you could always install the coilovers, and then take them off and restore to stock for resale.

KW coilovers hold their money also so you won’t be losing out either way...

[ga41]

Don't forget that a damper slowly loses performance as the mileage piles on. It will be gradual and so won't be noticeable except when you install new OEM ones (to be an apples to apples comparison for example)... I don't know how many miles you have on yours but the Internets say that usually at around 100k dampers would generally need replacing.

[Audidude]

I don't know how many miles you have on yours

55,000kms, approx 33,000mi.

[ga41]

I don't know how many miles you have on yours

55,000kms, approx 33,000mi.

They should be fine then. You could have them checked out at your next big service to be sure. Along with bushing etc to make sure everything's in good condition and tight.

[Audidude]

Decision made:

After service and alignment being done the car is driving and tracking so much better. It had far too much toe-in on front and more particularly rear - all geometry now at factory settings for Z4 M Coupe. I think the M Division need some credit for knowing how to set a car up for the road. I'm not tracking the car.

Turn in is instant and accurate, and the rear feels more tied down - probably because it's tracking the steering inputs more accurately with the correct toe.

The ride is actually quite tolerable given the design brief. Remember that this is an M sports car, not a standard car on M Sport suspension. The differences in those two are huge.

[MrPT]

Sounds good. Do you know what settings you had before? There is a fair amount of rear toe in on the coupe, as stock.

[Audidude]

Sounds good. Do you know what settings you had before? There is a fair amount of rear toe in on the coupe, as stock.

I'll post up the pre and post settings when I get home - don't have them right now. The camber was OK.
Another thing that put me off "upgrading" was that most non-coilover options lower the car. To my eye the standard M Coupe ride height is perfect for the car, is already quite low, and lowering would inevitably lead to clearance issues with driveways.
I don't come from the modify-or-die school of thought
Besides, it's a rare collectible now - factory unmodified is always a plus.

[Audidude]

Note the high positive initial toe, especially in the rear! Now set to lowest limit of factory spec.

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