mx5cartalk.com

I fitted a new set of BC BR coilovers to a NA8 . Very happy with performance, not so happy with adjustability on rears, on the highest setting on rears (with 25mm still in thread in mount as required and a 5mm preload) I could only get 325mm (fender to centre of wheel). Fronts were no problem, lots of range of adjustability. 325mm is a good height, however leaves no scope for any settling of suspension or sag, I was aiming for 335mm which I understand to be the minimum legal height and also gets the suspension arms horizontal. I never wanted to slam the car, only improve the stance and driveability.

Looking at the base of the coilovers I saw that the fronts (marked F and fitted to longer strut with heavier spring) were about 20mm longer than the rears (marked R and fitted to shorter travel strut with lighter spring) . Convinced i had fitted the struts correctly front and rear I checked some measurements and, reluctantly , took the struts out again, this time swapping the front and rear lower threaded base. They are a straight swap, just screw them off and screw them onto new strut. Now my front struts have a base marked 'R' and the rears marked 'F'.

The upshot is I can now adjust the fronts up to about 335 (only wanted about 320) and the rears can be lowered to around 300 and raised to monster truck height.

There appears to be nothing dodgy with this, they dont foul anything, all the bolt holes and threads are the same etc.

Makes me wonder if they were incorrectly assembled? If they came with 4 of the longer mounts to start with they would have a perfect full range of adjustment.

I know at least one other member has had the issue of limited adjustability of the rears, hopes this can helps someone else.

interesting info. i wonder if the shocks are valved differently for the different front/rear spring rates?

I think the valving would be different front to rear given the different spring rates. I did not have to swap the shocks or springs, only the screw on base mounts. The front shocks and springs still remain at the front and the rear shocks and springs at the rear.

oh - i didn't read your post properly.

sounds like an interesting discovery indeed! from what you've described i agree that they would appear to be assembled incorrectly. i would get in contact with the distributor and tell them what you've found (if you could be bothered with this type of thing) - as you've mentioned the rear ride height issue has been an issue for a few forum members. i've been contemplating a set of coilovers and ruled out the BC BR due to concerns regarding rear ride height & travel. at least you've got the height issue sorted!

slightly OT, but what spring/shock combo were you running before, and how do the BC BRs compare? do you have any concerns regarding rear shock travel in the rear?

was running the original bilsteins (200k old) with king springs. Made for a harsh ride over bumps and a surprising amount of body roll when pushed in corners, over steer wasnt progresive nor very tidy. This in no particular reflection on the products mentioned, they were just past their use by date.

The BC's with the factory settings (5mm preload on spring, 8 on the damping setting) is less harsh, damping is more disciplined and oversteer much more predicatble and controllable. Havn't played with the damping (yet), seems good where it is..

As for the travel of the rear shocks.....looking at the shocks and comparing them to the bilsteins (which are huge in comparison) I think 'why the hell didnt they just make them longer?' There is plenty of length in the strut to do it. I havn't experienced the rears bottoming out so have no issue with it, but agree with those who have an issue, at least in principle, with the design. I also agree with those who just threw them in and drove them and dont have an issue with them! Don't overthink them, I believe they offer a good ride/product for the price.