I've been riding on Bilstein B14 adjustable coilovers for about 2wo years. Love them. However, during the past year I'd done some extensive 4,000 mi driving cross country loaded down with my belongings with the intention of moving. Ive noticed that due to the prolonged additional weight I carried, has caused my springs to start to collapse/ compress to the point I can no longer adjust to or near the factory ride height. As long as the strut cartridges have not failed I was hoping to just replace the springs. To that point I've made several attempts source these springs going as far as contacting the Bilstein manufacturer themselves - but to no avail and without response.
I haven't a clue as to what options exist for replacing these springs or (perhaps) ones like H&R springs (?) that might fit (?). Or are the B14 springs specific to these coilovers?
I'm hoping not to have to purchase a new set of adjustable coilovers.
As I've mentioned - I am completely clueless.

I appreciate any insite and constructive advice.
Thanks.

 

Seems to me, storage capacity constraints with associated weight on all that should have been offset by having travelled solo with the seats otherwise unoccupied. IIRC from one of your prior posts, you're not a heavy guy which helped to not overload rated chassis and suspension limits. If your springs have sacked-out, perhaps those don't meet Bilstein tensile strength spec - now or even when new.

With that stated, did you buy those Bilstein from ECS or other supplier which offers a Lifetime Replacement Program? If so, I'd consider pursuing that rather than attempting to source replacement springs (only)...

 

I can work with Bilstein, we are direct with them and might be able to find a source if not. Worth a shot.

 

Thanks to both of you for responding so quickly!
@MCS4FUN - Yes - Good call. I purchased my B14 coilovers from a vendor that states "Hassle-Free Returns & Lifetime Replacement Guarantee". I've never been one to haggle - Just hope that they stand by their word and drama free.
@ECSTuning - Thank you for that! I hope things go well with the vendor. If not, you can be sure I'll be working with you guys. Thanks for the offer to help!

 

Yep, let me try with Bilstein first. Just PM me the order number.

 

GP2 springs? From what I have read, R53 and R56 coilovers are basically interchangeable, with the exception of front upper mounts, and the rear trailing arm mounts if your R53 has the steel trailing arms. The springs should be interchangeable, and the GP2 springs are longer and stiffer than the B14 springs.

 

^^^Thanks. I'll check out info on the JCW / GP2 springs to see if it might be compatible with my existing B14 adjustable shocks/"piston cartridges". A more viable, stronger spring would be favorable.

What defines me as "clueless" with respect to my query and what concerns me: Is overall dimensions (L x W) of a non B14 spring replacement as well as the upper and lower circumference of the replacement springs as they relate to/fit the upper and lower perches of the B14 adjustable shock/strut assembly I currently have.
Having laid / compared the original factory struts side by side with the B14's during the swap (2wo years ago), I can't recall if there were any size differences between the springs. Best I can remember were the lower "perches" were different, as the B14 adjustable merely used a plastic ring for the lower spring to set upon. One other concern or question in mind was; Can any of these substitute (non B14 adjustable) springs withstand adjustability (e.g: lowering by compression)?
Thanks.

 

^^^ From my sig topic (post # 54 - Sept 2021) are these numbers on R53 non-coilover rear springs. From all that, combo of coil count and wire diameter affect unmounted free length. Installed ride height would also be affected by differences in steel wire tensile strength, assuming not an industry standard worldwide. If were mine, I wouldn't mix components from what Bilstein designed but instead, replace those springs with original spec - or replace the set entirely.

===============================

I wanted comparative measurements for my own info plus to post here for others that might be interested. When BMW announced the JCW Sport kit in November 2004, their claim was just 10mm drop whereas the Eibach Pro kit 5702-140 claimed 30mm drop (1.0" front / 1.2" rear.

So here are the rear numbers with this post to be edited later after the fronts are removed:

***************************EIBACH PRO***************JCW SPORT
FREE LENGTH******************8 7/8"**********************9 9/16"
WIRE DIAMETER***************11.4 mm********************11.1 mm
OUTER COIL DIAMETER**********4"**************************4"
# COILS**********************7 1/4***********************6 3/4
(sorry about table format - why can't we embed bitmap images here?)

In theory, the JCW coils might be just a bit stiffer with apparent longer wire length but slightly smaller wire diameter seems might offset. Regardless, raising suspension for increased ground clearance should restore adequate room for planned taller 215/45R17 Michelin Pilot Sport 4S tires vs the super low profile 205/40R17 Toyo Proxe RA1 on now. Also noting the Eibach bottom coil stack suggests different rate otherwise than the JCW.

 

Very good pertinent and important data to consider. Makes very good sense. I will try to investigate/find the specs for the B14's by comparison.

One more note I should add is that; It seems that my front springs are less affected as I still have a fair amount of threads left to adjust the fronts to near stock height.
The rears on the other hand, have "sagged" considerably (given that the weight carried were in the rear) and definitely need replacing before the shocks start bottoming out.

Thanks again for the input!

 

I had the B14s on my R55. I liked them out of the box, but also felt they sagged a bit in the rear after a while. I adjusted the rears higher twice, but still felt they were too low in the back.

Since the B14 springs are designed to use stock upper mounts, you’ll need springs that will work with the adjustable lower perch, but still be sized for the upper OEM mounts. That’s why I suggested the R56 GP2 springs. The GP2 suspension was a modified B14 setup. The springs were stiffer and longer, and the shocks are B14 build with slightly different damping curves to accommodate the stiffer springs.

R53 B14 kit:
https://www.ecstuning.com/b-bilstein...47-126916~bil/

R56 B14 kit:
https://www.ecstuning.com/b-bilstein...47-139060~bil/

R56 GP2 kit:
https://www.ecstuning.com/b-genuine-...31306858041kt/

Replcement GP2 springs:
Front - https://www.ecstuning.com/b-genuine-...h/31336858045/
Rear - https://www.ecstuning.com/b-genuine-...r/33536858046/

 

Thanks.
I followed your recommendation and searched a bit and did some reading on the GP/GP2 springs. Although I still couldn't find definatve specs on the B14 springs for a Mini, to cross reference; but info on the JCW / GP / GP2 setups mention a correlation between Bilstein and vaguely H&R.
I did come across the ECS website (as you'd posted), and seemed to me to be the most informative as I am more of a visual person. I felt pretty confident as the GP2 springs would be my best option for spring replacement.
The price scares me. The total cost would be more than half of what I paid for my B14's coilovers.

notwithstanding <
Since I'd landed out here in the desert, a year ago - I've dropped nearly $4k into my Mini just on routine maintenance (oil & trans fluid chages, 4 new tires, alignment, new rotors/brakes, all new upgrade mounts, exhaust/CAT, paint correction, new windshield etc...).
Stop me if I'm whining >

Perhaps I can afford to get by with just doing the rears with the GP2 springs for now?
However, I'm a little concerned with repect to the length being taller and adjustability with the GP2 as l prefer a lower stance.
Still much to consider but the input has been very helpful!

 

PS/Addendum :
I did consider spring spacers (for the time being).
However, I've never used them before. In my mind they may cause more damage to the current setup e.g: stressing the springs potentially causing them to break (?)....
Any thoughts on that?

 

Let us know, they can get the springs, its special order only and not sellable on our web front and will take some time. If you do decide it will have to be a request through CS team and they can help you out.

 

@ECSTuning Thank you very much for looking into that for me!

 

Well, with the assistance of a fine vendor here on NAM, I was able to place an order directly to Bilstein for a pair of B14 replacement springs. This was back in November 2025. Since then/to this day - I'd received several backorder/shipping dates. I waited and waited and waited...It was suggested that the springs maybe NLA.
I am in desperate need of replacement springs. As of now the springs have completely sagged beyond its limits.
I am still in the mindset/financially of hoping to get by with just replacing the springs and have been looking into H&R sport springs. However I'm a bit confused as to search results continue to show H&R sport "LOWERING SPRINGS" is there a difference between "sport springs" and "lowering springs" within the H&R brand???
I'm a bit confused.
I have adjustable (B14) coil overs. I really don't want to lower the stance by more than an inch. I just want stiffer lasting springs.
I would appreciate any light/clarification you might have regarding this.
Thanks.

Aside note:
I would've preferred investing in the GP2 springs but the ship date is just too far out...and learning the hard way that there is no guarantee they might be back ordered as well.

 

The “H&R Sport” springs and the “H&R Lowering” springs are the same thing. Also, they will only work with stock style struts, since they rest on the stock lower spring perch. Your aftermarket Bilstein coilovers do not have an OEM style lower spring perch, so they won’t fit.

 

Thanks again for the quick reply!!
Out of desperation I almost pulled the trigger on a set of those. As much as I like the ride height adjustable feature of these coil overs - I don't see it in my best interest to drop another $1,300 in another set. It's looking like my best cost effective option is to go back to stock ride height - Perhaps B4s again... (?)

 

.
these BMW guys did some spring swaps on their Bilstein coilovers

dunno if applicable for MINI though?

https://f30.bimmerpost.com/forums/sh....php?t=1699435

.

 

That look very interesting! Thanks for sharing. Would just need to figure out the upper spring perch….

 

would it work to install these commonly found plates?
they can be found either adjustable or fixed . . .

. . . then it would just be a matter of finding the springs

is this spring rate info accurate:



i prefer metric so would rather think of those numbers as 5.75K front and 4K rear --- is that a correct conversion to the listed numbers above?

and it appears that the B14 setup uses a helper spring in the rear, must that be retained if using different springs?

if not, how would deletion of the helper spring affect ride quality or spring rates?

Hyperco does have helper/tender springs easily available tho:

https://www.hypercoils.com/shop/helper-springs

what are the pros/cons of using helper/tender springs?

 

who makes the springs for Bilstein?

the above example just snapped, but given they were fitted to a car in the harsh conditions of Canada, that pic is from a Focus ST owner and in the same thread someone else posted a pic of their modded B14's -

https://www.focusst.org/threads/bils...5#post-2671651

- but his choice of Vorshlag plates makes his setup an expensive proposition.

i suppose you'd also need these in addition to the plates for the conversion?



https://shop-fortune-auto.com/collec...lacement-parts

?

 

Thanks @Oldboy Speedwell , I came across and watched that video (several times), last year while searching in vein for the original replacement springs. I'd thought the same = "Why can't just use a different spring that will fit that have the same top and bottom perch / coil over specs as B14s?". It was then that I happened upon that video.
I'm definitely an inventive kinda guy. but I seem to get lost in all the science and physics (coils, spring rates, rebound rate...etc) that deter me from messing around with Mini in this manner. Case in point to your reference regarding "helper springs" - I don't see them on my rear coils overs.
Are they in the monotube?
The spec sheet you posted above for the B14 spring rates is accurate. The OEM stock spring rates original to the Mini were a bit higher : 343lbs front & 286lbs rear.
I agree opting for fixed camber plates in front.

 

i'm not familiar with the B14,
but when searching to see them i saw this so figured it was an accurate depiction . . .

 

WTH?
Those do indeed look like the B14s. Except my rears don't have the "helper springs" as shown in the image above.

 

have you tried lately just typing in the part number and see if anything comes up?

that would be the easiest ideal solution if a lucky find popped up!

a bummer that it seems to be a difficult endeavor to simply get the direct replacement part.