Can you elaborate on "preload"?
I am shamefully not very well versed or knowledgeable.
My thought was that, if the suspension was lowered, the stock end/drop links would be too long for the sway bar to be properly effective.(?)

 

IMO, sway bars shouldn't be "preloaded", since they're basically a lateral torsional spring. Within reason, minor differences with end links of same length cause those bars to pivot up or down within their respective bushings, which doesn't create preload. I'm open to differing perspectives...

 

I think I get it now. For instance if you were racing in a circle track it would/could make sense to have one drop link shorter than the other ("preloaded" on one side)....(?).
Daily street driving conditions may not apply to this logic...perhaps(?) - So stock length drop links on a lowered suspension would be fine?
Correct me if I'm still not getting it right.
Thanks

 

Pictures worth 1000 words…

 

I don't disagree with the video demo, however IMO adjustable end link(s) shouldn't be necessary for most. My thinking is that if there is static imbalance side-to-side or corner-to-corner, determine why and attempt to correct that first. In my own R53 case, I took extra time while installing replacement springs on struts/shocks to ensure spring pigtails were fully clocked into the rubber seats. If after that and if loaded static heights aren't within "reason", coilovers with adjustable height rings are an option but for practicality (even if OEM stock), some dimensional variation is considered normal.

Also, circle track turning orientation usually handled with tire stagger and diameter, i,e., smaller on the turn-in direction rather than with sway bar preload (although that might be used as well - unsure)...

 

If you finish the suspension work and it is still clunking, look at the rubber grommet around the shaft for the rear wiper arm that goes through the rear window, it is is worn it will make a clunking noise as well.

As for the sway bar drop links, if you are lowering the ride height / modifying the suspension geometry enough to see a need for adjusting the drop links, you probably need to adjust the drop links.

If you are after the last little bit of performance, I recommend that you adjust the drop link to keep the mounting end of the sway bar level with the bushing mount on the body, If it points up or down, you are effectively shortening the torque arm of the sway bar in relation to the ground. Yes it may be the same length but if it is not level with the ground the relative torque is decreased. Granted a 15 or 20 degree change may not be an issue on the street, but if you are looking at adjustable drop links, you may already be looking for that last little bit of tuning advantage so things like this make a difference. I would not run anything suspension part that does not have rubber (or in a few select places poly) on the street. The end links in that video may prove to be too harsh for you during normal driving conditions

Just keep one thing in mind, race cars are garage queens. When not on the track, they are in the shop up on jack stands. Where a race car can go 5 to 500 miles between major inspection/parts replacements, the street car can go 10,000 miles or more between inspections/parts replacement. Also, the crew chief/mechanic seldom cares about how rough the ride is for the driver. You may have to decide when it becomes too uncomfortable for you and your passengers.

Just my 3 cents worth (normal 2 cent cost adjusted for inflation)

Jeff

 

Thank you for putting that into terms, my ineffable language failed to describe above.
That was exactly my thought with respect to drop link length in relation to swaybar.
Although, in addition to drop links (I went with new stock), I have held off installing the Koni adjustables - while I've kept the car at stock height for now.
Thanks again for your 3¢

 

Ok - Belaboring this older/previous subject I had posted.

Cutting to the chase -
The Short Version:
I discovered the clunking noise was due to a loose Rear wheel well liner and not due to any mechanical failure!

The Long Version:
Preface:
I had initially posted a question with regards to my Mini making a soft clunking/"rattle" noise emanating from the rear suspension while driving slow over uneven pavement and speed bumps. Although a bit annoying. - It wasn't too concerning.
However in hopes to eliminate all possible causes; Upon inspection; Interestingly enough, the trailing arm bushings were super solid and everything suspension wise was tight and showed little to no signs of wear (!?!).

Regardless (i.e. throwing $parts$ at it ) in effort to resolve :
Since the time of my original/this thread; I purchased and replaced a fair amount of (suspect) rear suspension parts:
_R&R factory w/Rear Adjustable Camber control arms
_Drop links
_OEM Factory swaybar bushings
_Bilstein B4 rear shocks
_and recently purchased a new 22mm Alta RASB(rear adjustable sway bar).

Having replaced all the aforementioned, (except for the ALTA RSB), for months the soft clunking remained audibly present. Nothing changed

Epilogue:
Yesterday morning I got up the nerve to finally replace the factory RSB and install the 22mm Alta. Everything went as smooth and easy as it possibly could have.
Early this morning, I took the Mini out for a (test) drive to a DIY carwash so I could pressure wash the undercarriage. Not surprising = the soft clunking noise remained at slow speed. WTF??
While pressure washing the sub frame/undercarriage, I heard a familiar sound. A soft clunking!
It turned out that everytime I went over the R Rear passenger side wheel liner (in front of the R rear wheel = the plastic area that conceals the ABS & Brake wear sensors ), with the pressure washer - The plastic liner flexed, vibrated, hitting the under body wheel well.
Thus making the soft clunking, rattle sound!
Since there were/are no apparent retaining clips in this area; A small dab of my favorite adhesive (E6000) inconspicuously placed between the liner and metal wheel well solved a year long mystery.