E86 Suspension

[curvature]

I've just had a trip in my friend's E85 and it is a lot smoother and generally quieter over bumpy sections of road compared to my E86. My car is on 89k and his around 75k.

I'm looking to make the ride in my car a little more compliant so based on the information below would any of you nice people offer some advice on what you might now start to do to the car please?

Nov 21, advisory on the MOT -

"Front Suspension arm pin or bush worn but not resulting in excessive movement Offside and nearside lower suspension arm rear mounting bushes have movement/play (5.3.4 (a) (i))"

Last Nov the car had both front lower suspension arms replaced and drop links.

In July 2017 it had new front shocks, springs and bump stops. (Bilstein B4) Looking at the MOT history this was around 30k miles ago now.

Thank you.

[PDJ]

Does the B4 have internal bump stops

If it does and you have fitted external bump stops this could be why it is a bit crashy as the free suspension travel would be around 20mm in bump, before it is compressing the bump stops.

[curvature]

Does the B4 have internal bump stops

If it does and you have fitted external bump stops this could be why it is a bit crashy as the free suspension travel would be around 20mm in bump, before it is compressing the bump stops.

I need to look into this as I only got the car in February this year so it is all new to me. Thanks for your comment.

[Zulu4]

Does your friend's E85 have standard or sport suspension (like your E86) ? Standard suspension has slightly longer springs.
Also, have you got runflat tyres ? They are bad for comfort.

[curvature]

Both are sport models and on 18” non run flats .

[Dark Diggler]

It’s worth checking the bolts on the strut braces, if they are the slightest bit un tight it can sound like bad suspension.

[Dark Diggler]

Also, did they change the top mounts when they changed your dampers and springs?

[Beesza]

The e86 is inherently a stiffer car than the e85 due to its roof so you would feel the jolts more, all other things evening equal.

Tyre pressure can make a huge difference. When I run my e86 (18” Michelin PS4) at stock pressures, the car is very crashy. Dropping to 32psi is a night and day difference

[Z4Mariner]

I agree with Beesza, the tire pressures will make a difference. My new-to-me coupe came to me with tires filled to about 35 PSI. I dropped them to 32 PSI, and the ride seems to have the balance I want between too-soft and too-harsh. Tires are 18" Goodyear Eagle Sport non-runflats, and since they have plenty of tread left, I'll run them for at least this Summer before I consider new tires.

[Bob123]

curvature, I'm interested to see the outcome of this as I feel that the ride of my car is a bit 'crashy'. Mine's fitted with standard 17" wheels, M-Sport suspension (it's an SE but I believe that UK spec 3.0 E85s got M-Sport suspension automatically) with Bilstein shock absorbers and runflats on the rear, none runflats on the front and yet to check the type of front shock absorbers. I've been inflating to the BMW recommended tyre pressures.

[BTZ461]

Its a sports car. Ditch the runflats quickly. Tyre pressures 30 psi on all four corners

[Bob123]

BTZ461, I've owned quite a few sportscars, including a Lotus Elise mark 1 so I have a pretty good feel for sportcar suspension. Thanks for the info. I will be trying different tyres pressures and ditching the runflats as has been advised previously, though I find it strange that BMW specify pressures that people think are too high. I'm interested in shock absorber and spring setups too as these play a major part in how the suspension behaves.

[curvature]

I agree with Beesza, the tire pressures will make a difference. My new-to-me coupe came to me with tires filled to about 35 PSI. I dropped them to 32 PSI, and the ride seems to have the balance I want between too-soft and too-harsh. Tires are 18" Goodyear Eagle Sport non-runflats, and since they have plenty of tread left, I'll run them for at least this Summer before I consider new tires.

I have the same tyres so will have a play with the pressures.