[Jme_be]

Hi all

I've just had the Bilstein B12-Pro Kit fitted to my 2008 E92 330i by Thorney Motorsport. £1250 supplied and fitted. In summary, I couldn't be happier with the B12-pro kit or the exceptional service from Thorney Motorsport (Staplegate Farm, Crowfield, Northants, NN13 5TW, Tel. 01280 850 102).

I did have thoughts of slamming it to the ground and going for one of the adjustable sets, however I very rarely do track days and wanted to keep the car comfortable as an everyday road car whilst improving on the handling from the stock M-Sport items.

First drive impressions

The first thing that was immediately obvious just driving out of the carpark was a directness to the steering, not heavier but seemingly a greater amount of turn for the same amount of steering input. Once onto the road this feeling continued and was clearly evident when going over the first roundabout. Turn-in was far keener and precise. Where the car previously felt like it would understeer, it now grips and turns much more. The best way I can describe the difference is from old to new would be almost like comparing the difference between worn tyres on the front and putting new premium tyres on. My tyres were already correctly inflated BTW. ..It would be interesting to know how much of the steering-feel change is due to the geometry changes and how much is due to the new dampers + springs. As an aside, one interesting fact emerged from a chat with the mechanic that was working on my car - the track-control arms had not been adjusted in a long time. The nuts were seized to the point that he had to not only use penetrating oil, heat and a spanner with a very long handle, but he had to also leave the nut soaking in penetrating fluid in a custom-built bath for several hours in order to free it off. So what? My car with 68k miles on the clock, has a full BMW franchised dealer service history – i.e. the dealer has never adjusted it yet it is supposed to. It may well be that the dealer did not feel it needed adjustment, but I suspect that the toe-in was within ‘acceptable limits’.

Once I got used to the lovely new steering-feel and turn-in, I then began to tune into other aspects of what was different. The ride. Smooth, oily damping yet not stodgy or heavy. If anything the car feels lighter yet definitely deals with bumps far more competently. It makes the M-Sport suspension feel almost wooden/brittle/unforgiving by comparison. I’m not entirely clear how the suspension can feel more compliant over bumps yet provide better steering and turn-in response, but it does. You would probably expect the car to roll more but it doesn’t.

The next thing that I began to feel was a feeling of more weight over the back wheels – the closest way I can describe this would be how my car felt after putting a bag of cement in the boot a few weeks ago. However the difference being that the car doesn’t feel heavier, just that the rear tyres feel ‘pushed’ into the tarmac. This isn’t simply just a feeling but is confirmed with great traction under hard acceleration – I tested this on a couple of my favourite bends where I could guarantee that the traction control light would flicker at certain points. I gave it the full beans at exactly this point and only get the slightest flicker whereas the DTC would’ve previously backed the power off whilst flashing constantly. As the rain began to fall I then started to appreciate that the front tyres also feel like they have more grip, certainly I have much more confidence and more easily able to feel the grip. Quite impressive.

Looks

OK, it may not have the Need For Speed, gravel-grinding, low-rider look (which I do quite like!) it is definitely lower than the standard M-Sport. Interestingly, the back has dropped slightly more than the front relatively (i.e. the car does not look like it is raked nose-up, but looks flat – I’d say the rear has dropped maybe 7mm and the front has dropped maybe 4mm) – the relative drop rear to front is confirmed by the fact the headlight aim needed to be adjusted downwards after fitting. I’ve read a lot of people talk about ‘settling’ but have also seen that Eibach springs suffer very little with settling. Time will tell. When you look at the car it looks fine to me, with both front and rear arches looking closer to the tyres than before. All I can conclude from this is that the standard M-Sport setup has both front and rear ride heights too high, with the rear too high in relation to the front.

In conclusion I am very pleased with this kit and the geometry work that Thorney Motorsports carried out – although there is no adjustment on the B12 kit itself, there is geometry setup on the car itself. Not just front toe-in, but also (unbeknown to me) the rear toe-in can also be adjusted (if you have the right measuring equipment – which Thorney does!). So whilst any garage can fit this, you need to find one that it competent at full geometry adjustment ..to think that I at one stage was thinking about asking the Ford garage down the road to fit the springs and dampers if I supplied them!!

If I wanted the slammed-look and didn’t care about driving dynamics on typical UK roads, or I lived on a racetrack or had access to lots of smooth tarmac, I would recommend the other adjustable kits with stiffer, shorter springs. For me, the B12 Pro kit (and professional fitment) has done everything I’d hoped for: improved turn-in, steering-feel, cornering grip, traction and improved comfort. Love it.

Some photos of the kit being installed on my actual car on Thorney Motorsport’s website (how cool is that!) - http://www.thorney.ms/bilstein-b12-suspension-kit.html

Pictures - saved in sepia to contrast wheels against bodywork - in full colour the black paint against the tyres made it almost impossible to see the gap

Top picture - before
Bottom picture - after

[R.G.]

Thanks for the write up.
Let us know your impressions of the kit after driving on them for a bit

[Jme_be]

No worries

After 1 month of driving all my initial thoughts are still there. Compared to the standard M-Sport suspension I had before -

The ride is lower and more absorbent, kind of like it is using more travel than before. I'd say that that the biggest change is at the back which feels significantly more planted with more grip / softer. Front also feels like it has more grip, however doesn't feel any 'softer' but does feel like it absorbs bumps better. (I know, sound's weird saying not softer but aborbs bumps better. You have to feel it). As I mentioned in first post, even without any measuring, car has dropped front and back, and as the headlights needed to be adjusted down after the B12 kit was fitted, clearly shows that the back has dropped more than the front.

Cornering and braking are definitely flatter. I did find with the original M-Sport that I would get a tiny amount of weave, braking as hard as possible from high speed - as if the rear wheels were lifting off the tarmac. That's gone - braking is much flatter now. Same sort of thing with cornering - less body roll. Maybe it's the slight lowering of the ride height (although it's probably only maybe lower by 5mm front and 7mm at the back).

The ride height hasn't changed (as far as I can tell) between when it was first fitted, and after a few weeks of driving - matching Eibach''s claims that the springs don't suffer from settling compared to some other makes.

I'm happy with the improved handling and very happy that is has managed to do this and make the car more comfortable. I would definitely recommend as an upgrade to the standard M-Sport suspension. It's always a subjective thing as to the question - is it worth the money? - I find that most people that spend money on their car will justify the cost in forums and down the pub ..and to the wife (if you tell her!).

..If you're not quite at that stage yet, I would also recommend leaving the standard suspension on (until it needs replacing) and in the meantime take you car along to a garage that can do a full geometry setup front and rear - I've found that most tyre-fitting places have the laser systems to adjust front toe-in and that's it. I was surprised to see that the garage I took my car to was also adjusting the rear alignment (I think it must be toe-in?) - I didn't think this was possible on BMWs with otherwise standard running gear, but I saw them doing it with my own eyes - also saw that the rear alignment was a fair way out from 'optimal' - not sure how they adjusted it though..? Getting the alignment done alone will possibly make your car very different for a fraction of the price (turn-in, understeer and steering feel).

[danb21t]

Hey there,

Just looking at your write up, looks positive!
How are you finding it after a few months?

Can you confirm that your B12 kit is the same as this:

http://www.europerformance.co.uk/pag...sub_category=1

Going by the specs on that page your car doesn't look to have taken the drop quite as much as I would expect.
I was set on getting the money together for a B14 kit but realistically once setup I'm never going to adjust the height so may just settle on the B12 kit.

Cheers!
Dan

[Blackhawk36]

JME Be. The product description says that it lowers the car 40mm. Are there any adjustments required to the other suspension components to compensate for the lowering?

[Jme_be]

Hi Dan, yes still very pleased with the improvement. I have since removed the spacers from the front and reduced the spacers on the rear to 12mm (was 12mm Fr / 15mm R). Not due to any rubbing issues, but more down to an increased amount of steering weight and tramlining compared to stock ..my mate who also has an E92 (stock) drove my car after I had the B12 Pro kit fitted and immediately commented on the steering feeling heavy. I wasn't sure if this was due to the spacers or the suspension - it was the spacers. Running stock wheels/tyres without spacers on the front definitely feels much better!

Difficult to say if the kit in the link is correct for your car - to be on the safe side I'd recommend checking the product code for your car direct from Bilstein -

http://www.bilstein.de/en-uk/product...ine-catalogue/

..the B12 Pro kit comes with several different product codes - they produce slightly different variations for different engines. The 335D kit will presumably have slightly stiffer springs given that the engine is heavier than for my car (330i).

The ride height change is, I believe, quoted against the standard BMW suspension, not the M-Sport ..the BMW M-Sport suspension is lower than the standard BMW (SE) suspension.

Annoyingly, I didn't take actual measurements with a tape measure before and after, however it is definitely lower (car now catches on standard-height kerbs - read damaged bumper!) and following fitment of the B12 Pro kit, headlights needed to be adjusted downwards - i.e. the rear had dropped more relative to the front.

For my car, I now estimate that the front has dropped by 10-15mm and the rear has dropped by 15-20mm (against the original M-Sport suspension). I think the theory behind the rear dropping slightly more relative to front, is to improve rear traction by biasing a little more weight to the back. This doesn't appear to have increased under-steer at all, I'm guessing, due to improved front-end grip. ..and my car now only has spacer on the rear which in theory increases under-steer.. If I do want to change the balance, I'll remove the rear spacers too.

I looked at the B14 kit also - more costly, firmer and you really need to get a garage that is not only familiar with installing after market suspension but also one that ideally has fitted to the E92. Otherwise they will pick front and rear ride heights initially by what 'looks right' - I would bet that some would go for a more aggressive rake on the car, putting the front lower than the rear, because that is a good rule of thumb. Problem with that approach is that you will need to get the B14 kit fitted. Take for a drive, adjust, take for another drive, adjust, go home, drive for a few weeks and then decide you want to adjust again (partly because you can). Chances are that you will eventually get the car setup exactly how you like it with the B14 but it will take a lot of time and money - unless you're going to do it yourself. Adjustable suspension for me was ruled out exactly on that basis - the Eibach B12 Pro kit is designed specifically for your car and fixed like that - benefits are ease and speed of setup and that you can't ruin your car's handling. The obvious drawback is that if you don't like the way that Eibach have setup the damping/spring rate/ride-heights for your car, there is very little you can do about it.

In summary, for me, the B12 Pro kit was a good value upgrade over the standard M-Sport suspension, perfect for street/road use. Better handling, better traction and much better over bumps.

[Jme_be]

Blackhawk - see my new post above which includes ride height. The figures quoted by these websites and Eibach are (I believe) against standard ('SE' in the UK) BMW suspension. The BMW M-Sport suspension that I had fitted prior is already lower than the standard BMW suspension.

No other adjustments are 'needed' although the garage that I took my car to also runs a race team running an E92 M3 - they asked me what sort of driving I mostly perform and suggested changes which included front toe-in*. The toe-in should be checked afterwards and set to standard BMW configuration unless you specifically want to make some fine adjustments. The B12 Pro kit can not be adjusted itself.

You will need to check headlight alignment afterwards - this is noted on the Eibach installation guide notes.

*the garage also adjusted the rear although I'm not sure if this was toe-in or camber - I didn't think these things could be changed on a standard E92, but the garage were definitely able to do so. When the had the alignment rig fitted they asked me if I'd ever knocked the rear left hand wheel into a kerb as it was out (not by me!) - they adjusted something on the back to bring it back into correct alignment.

[Jme_be]

..I have referred to the kit in places as the 'Eibach' kit - for clarity, it was the Bilstein B12 Pro kit which uses Eibach springs. Not sure if Eibach produce their own kit with Bilstein dampers!

To check correct kit for your car, go here - http://www.bilstein.de/en-uk/product...ine-catalogue/

[D's Bimmer]

I just installed the B12 kit and front M3 arms a few days ago. Big difference over stock for sure. Now that you have a few months with the B12's, how do you find them?

[Jme_be]

D's, good to see that you've gone with the same kit. I've heard lots of favourable things on the M3 arms (and bushes) too. May look at doing that.

I'm still impressed with the B12 pro kit. The Bilstein dampers are much smoother than the original M-Sport. The Eibach springs are definitely softer than the original M-Sort which helps with traction and grip, whilst ride quality being also improved. Although softer, the improved damping/slight reduction in ride height means that there isn't any more roll than before, possibly less, difficult to be sure.

On my commute there are a series of roundabouts that require a relatively sharp right, left steering input. I do sometimes think I get more understeer/push than I'd ideally like and whether or not I should invest in an anti-roll bar/sway bar, but other than that, I still think that the B12 Pro kit is extremely well suited to street driving. The traction, grip, bump-absorption, comfort and sensible ride height (fractionally lower than M-Sport) are big ticks for a street car.

If I did lots of track days I would probably go for the more expensive and firmer adjustable kit, a trolley-jack and some new spanners! ..I like the fact that this kit is optimised and offers no tweaking options - ie. I can't ruin the setup with experimental changes!

[D's Bimmer]

Originally Posted by Jme_be

D's, good to see that you've gone with the same kit. I've heard lots of favourable things on the M3 arms (and bushes) too. May look at doing that.

I'm still impressed with the B12 pro kit. The Bilstein dampers are much smoother than the original M-Sport. The Eibach springs are definitely softer than the original M-Sort which helps with traction and grip, whilst ride quality being also improved. Although softer, the improved damping/slight reduction in ride height means that there isn't any more roll than before, possibly less, difficult to be sure.

On my commute there are a series of roundabouts that require a relatively sharp right, left steering input. I do sometimes think I get more understeer/push than I'd ideally like and whether or not I should invest in an anti-roll bar/sway bar, but other than that, I still think that the B12 Pro kit is extremely well suited to street driving. The traction, grip, bump-absorption, comfort and sensible ride height (fractionally lower than M-Sport) are big ticks for a street car.

If I did lots of track days I would probably go for the more expensive and firmer adjustable kit, a trolley-jack and some new spanners! ..I like the fact that this kit is optimised and offers no tweaking options - ie. I can't ruin the setup with experimental changes!

So after having the B12 kit on my car for about a month, I am very happy with it 80% of the time. I find it can be rather stiff and jarring when driving at slower speeds over rougher roads. I am still in my winter run flats and the stiffer sidewalls absolutely impact the ride quality in a negative manner. I am hoping that once I switch over to my summer Michelin PSS's in a few weeks that the ride quality will improve to the point where I am 100% happy.

Are you on run flats?

[Jme_be]

Originally Posted by D's Bimmer

So after having the B12 kit on my car for about a month, I am very happy with it 80% of the time. I find it can be rather stiff and jarring when driving at slower speeds over rougher roads. I am still in my winter run flats and the stiffer sidewalls absolutely impact the ride quality in a negative manner. I am hoping that once I switch over to my summer Michelin PSS's in a few weeks that the ride quality will improve to the point where I am 100% happy.

Are you on run flats?

Not sure how BMW brand their suspension options in Canada but I recall reading that the M-Sport suspension isn't as popular, so did you have 'standard' suspension / did the new suspension noticeably lower your car? The B12 kit is somewhere between standard BMW suspension and their M-Sport suspension in terms of ride quality IMHO - my E46 coupe was on standard BMW suspension and was much smoother - although it had 17" wheels - ride height was at least an inch higher than my E92 now - overall it was much softer in the turns and rolled more. Still very grippy, but the time it took from leaning one side to the other, meant that it just couldn't change direction anywhere near as fast.

With the ride height of this B12 kit, the body control, improved traction and being noticeably smoother than the M-Sport suspension is quite an achievement. With less travel than standard suspension it will get bouncy/harsh/lose contact sooner that standard suspension of course. There is a road not far from me that is so f**ked up, it will scrape the plastic spray/aero flaps in places at speeds over 30mph - to be fair even guys in their 4x4s slow down!

I took the runflats off of mine as soon as they wore out. I put on Goodyear Eagle F1 AS2. I also experimented 1-3psi +/- over the recommended pressures which can also help - I ended up keeping the fronts at the standard pressure and reducing the rears by 2psi. You're quite right though, non-runflats alone can make 'almost' as much difference as a suspension change. The new runflats are supposedly much better but I don't see the point. I've got the BMW repair kit and pump in the back. Worth looking at places like the EVO etc. tyre tests - amongst the non-runflat tyres are some that with the standard load ratings give a softer ride which may be a consideration if the road surfaces are poor.

[D's Bimmer]

Originally Posted by Jme_be

Not sure how BMW brand their suspension options in Canada but I recall reading that the M-Sport suspension isn't as popular, so did you have 'standard' suspension / did the new suspension noticeably lower your car? The B12 kit is somewhere between standard BMW suspension and their M-Sport suspension in terms of ride quality IMHO - my E46 coupe was on standard BMW suspension and was much smoother - although it had 17" wheels - ride height was at least an inch higher than my E92 now - overall it was much softer in the turns and rolled more. Still very grippy, but the time it took from leaning one side to the other, meant that it just couldn't change direction anywhere near as fast.

With the ride height of this B12 kit, the body control, improved traction and being noticeably smoother than the M-Sport suspension is quite an achievement. With less travel than standard suspension it will get bouncy/harsh/lose contact sooner that standard suspension of course. There is a road not far from me that is so f**ked up, it will scrape the plastic spray/aero flaps in places at speeds over 30mph - to be fair even guys in their 4x4s slow down!

I took the runflats off of mine as soon as they wore out. I put on Goodyear Eagle F1 AS2. I also experimented 1-3psi +/- over the recommended pressures which can also help - I ended up keeping the fronts at the standard pressure and reducing the rears by 2psi. You're quite right though, non-runflats alone can make 'almost' as much difference as a suspension change. The new runflats are supposedly much better but I don't see the point. I've got the BMW repair kit and pump in the back. Worth looking at places like the EVO etc. tyre tests - amongst the non-runflat tyres are some that with the standard load ratings give a softer ride which may be a consideration if the road surfaces are poor.

Thanks! I am excited to get my summer Michelin PSS's on in another week or so. Hoping that will be the final piece of the puzzle to smooth out this very good suspension upgrade.