Z3M ARB Bushes

[Guest]

At the Llandow track day I experienced a little more body roll that I was expecting. I know stiffer ARBs would help, as would poly ARB bushes, so no need for any comments here. Since I have not owned my ///M from new (37k when I got it) and it has now done 53k, I wondered how much of that body roll was down to the front ARB not being as effective as it was when the car was new. As an experiment I replaced the ARB bushes with new ones form BMW. They were only £7 each, so not an expensive item.

I am quite surprised wit the result. The new bushes have reduced body roll a noticeable portion, so I guess the ARB is now working as BMW intended. Here are some pictures of the old and new bushes side by side. You can see noticeable wear, but what you can’t see is how soft the old ones were compared to new. Quite a difference.







It’s a simple job to change, 4x13mm nuts to remove. I didn’t need to jack yup the car, but ramps would make life easier. All in all, about 20mins total.

The moral of this story is next time you plan an upgrade, think about how the car might have been when new. Maybe new stock is all you need.

Si.

[tuxman]

Thanks Si good tip ,we have just started our first stage of mods and have just fitted a set of Koni adjustable dampers ,they have improved things alot !!!!

Do you have the part no of the rubbers ??
thanks Simon

[ZZZEMMCO]

Si, good thinking--bushes lose their flexible absorption and need renewing from time to time depending on time/milage.--BUT--the benifit of fitting say bigger H & R rollbars has moved on since the ZR was designed.

Many drivers think that more power is the answer to their needs, but its How one can USE the power by better & safer road holding that makes all the difference.

[Guest]

Si, good thinking--bushes lose their flexible absorption and need renewing from time to time depending on time/milage.--BUT--the benifit of fitting say bigger H & R rollbars has moved on since the ZR was designed.

Many drivers think that more power is the answer to their needs, but its How one can USE the power by better & safer road holding that makes all the difference.

Quite right John! The ///M has more power than I will ever need I just need to use it correctly.

Changing these bushes has made me think about changing other old parts for new standard ones. I have just picked up a pair of front control arm bushes and rear trailing arm bushes to see what difference these make. I'll report back on my findings.

BTW, that part for the ///M ARB bushes is 31 35 1 135 805 price £7.62 each plus VAT.

While we are at it, FRont control arm bushes are 31 12 9 069 035 cost £20.17 each plus VAT and the rear trailing arm bushes are 33 32 9 061 945 cost £12.17 each side (part number is a kit for one side, so 2 bushes ion the box)

I am also seriously contemplating new front control arms, but they are a bit pricey.

Si.