[Watsey]

...and says "hi all, hope you can help". I've browsed the Bimmer forums and threads for ages, but only just joined - looking forward to sharing ideas, experience and banter with you over the coming months.

I know the topic of suspension has been posted umpteen times before, but I'd appreciate your first-hand experience (rather than conjecture ) to help me make some informed decisions

I've had (company cars, therefore not modified) several 330D Series saloons and Tourings over the past 10+ years and my current car, owned and therefore not subject to constraints, (F31 330sD, 403s, adaptive M suspension, adaptive xenons, pro nav, Harman Kardon, Steptronic + paddles, storage pack) was bought earlier this year as Approved Used, but needs sorting : ride, brakes, and possibly a few extra horses (will post questions re brakes and engine separately). Current tyres are Bridgestone Potenza RFTs and are awful - hard, of course, and no grip.

The ride quality is hugely compromised (harsh, and too much uncontrolled movement through the chassis), but everyone knows that. Understeer is also very prevalent, and really holds the handling back. Like many here, I'm sure, I enjoy (ahem) a 'spirited' drive along our A & B roads and that's where the problems with the stock setup are most noticeable. Birds (hi Kevin) and ACS/Rossiters (hi Lorcan) have offered good advice, but your experience of the following mods on your 'daily drivers' would be much appreciated :

Tyres : take it as a given that there RFTs will be coming off. Which have you found provide a good combination of ride, grip, and longevity ? MPSS ? (PS2s on my E46s were excellent) Goodyear Eagle F1 ? Continental SportContact 5 ?

Objectives : slightly lowered, composed and controlled ride quality (firm isn't a problem), less roll, eradicate understeer.

Suspension options that I'm considering :

1. ACS springs; retain existing adaptive dampers (the fronts are due to be replaced under warranty). Do the adaptive dampers provide good body control, or are they simply not up to it ? Currently, i.e. with stock springs, I find them very one-dimensional, with poor overall control even in Sport and Sport+ but do they work better with improved springs ?

2. The same as 1. plus Birds B3 ARBs (or Birds B3 sport springs instead of ACS).

3. Full replacement suspension, either ACS RS kit (fully adjustable) or Birds B3 springs + dampers + ARBs. If you've had great results moving to full kits from H&R, and others, I'd love to hear about it.

Thanks all.

[Tengocity]

I have ACS springs plus Birds anti roll bars and adaptive dampers, and MPSS tyres.
Very happy with it as a road car now, still a bit soft for the track.
Nisfan has Bilstein PSS10 coil overs and GTSussex has ACS RS coilovers, but that's about it for those who post on here, who've gone beyond ACS springs.
I've been in a car on h&r springs and standard dampers and it was appalling as kept hitting the bump stops, so that's out unless you do some much better dampers too.

I know one person who has Birds springs and anti roll bars but that's on a 435d and birds still hasn't finished development of the xdrive cars. Surprisingly can't think that anyone has posted on here having done the full birds job on a sdrive diesel. Or any car for that matter.

[Watsey]

Hi, and thanks for the quick reply. Have the ARBs removed the understeer, or was it already largely cured as a result of fitting ACS springs ?

What do you think of the M Performance brakes ? I've seen very mixed reviews.

[Tengocity]

Dialled it out a lot. I have an xdrive so I'd guess that on a sdrive car there would be less. Can't be super ambitious with trying to throw it in to a tight turn but on the road it's very neutral now. The springs helped but that was all round improvement just to stop it being crap. The ARBs really helped with the driving character.

The brakes... On xdrive cars they have a softness at the top of the pedal travel in town driving. On the public road when in a spirited drive they're fine. Big stops on the autobahn then they're fine. 3 laps at Bedford and they went long and soft!

I've changed the fluid and added braided hoses but not been back on track again to check them. I will do EBC yellow stuff pads too I think.

[Watsey]

Thanks for the insights. Sounds like ARBs are required, and interesting to hear your experience re M Perf brakes (consistent with others). I won't be doing much track work, but I'm not yet convinced BMW's option hits the mark. My F31 doesn't have M Sport brakes, and they don't haul the car down quickly enough for my liking. I may notice an improvement moving from sliding callipers with single piston, nevertheless do some more research. Alcons from Birds look serious, but that'd be a substantial investment and may be OTT.

[teaston]

I am completely happy with the ACS springs, but it depends what you want, i wanted the ride height and firmness of the pre LCI E90 M Sport and that is exactly what the ACS springs have given me.

[Tengocity]

Originally Posted by Watsey

Thanks for the insights. Sounds like ARBs are required, and interesting to hear your experience re M Perf brakes (consistent with others). I won't be doing much track work, but I'm not yet convinced BMW's option hits the mark. My F31 doesn't have M Sport brakes, and they don't haul the car down quickly enough for my liking. I may notice an improvement moving from sliding callipers with single piston, nevertheless do some more research. Alcons from Birds look serious, but that'd be a substantial investment and may be OTT.

They look great but £3000 for something that I'd only see the benefit of on track is not something I can justify!

I think the arbs are great but so many folk only have there cars for 2-3 years on pcps on here that extensive mods are hard to justify.

I think now that more are buying 2-3 year old cars and planning to keep for a while then we will see some more adventurous modifying...

[Watsey]

The car will kept for a few years so less of a problem in terms of spending if it's going to add to the enjoyment. That said, the benefits have it be real and relevant - no-one wants a money pit !

[AlanYoro35i]

I can answer some of your questions even tho i am from a different platform.

I have the B3 suspension on my e92, i got it at secondhand price so even at that price i don't think it's worth the money, let along brand new!!

When i had Eibach springs on a stock system, it had greatly reduced body roll but it's still there, but once i change to B3 kit, it was amazing. You'll understand the car more, can predict the characteristic of the movement more since the system is so much more progressive.

I would go for the springs if you're planning to retain the OEM suspension, Birds option would be good as i'm sure they would have a great spring for UK roads.

But if you would like other ideas then consider the Bilstein B14 kit, Height adjustable and are on a medium setting from the Full Fat B16 kit with 10 setting, tried my friends car with it on, performs similar to birds kit, but it highlights the need for better body control as this kit really allows you to push the car better and you would start noticing more weaknesses.

Bilstein B16 kit aka PSS9/10 kit - no need to say anything but if you can buy the birds kit then you can afford this kit but might be over killed so the B14 would be a perfect kit to fit in the middle.

Tyre's
Same problem on our E92 cars, we all change to Non RFT and we get more grip and softer ride, better handling depending on what tyres you use.

If you want the ultimate grip then go for Michelin pilot super sports, try it and you never go other brands. I have it on my 450bhp /4xx torque 335i and it give great amount of traction even on start up. so with torque rich diesel cars, it would be great!!

[teaston]

Originally Posted by Yoro35i

I can answer some of your questions even tho i am from a different platform.

I have the B3 suspension on my e92, i got it at secondhand price so even at that price i don't think it's worth the money, let along brand new!!

When i had Eibach springs on a stock system, it had greatly reduced body roll but it's still there, but once i change to B3 kit, it was amazing. You'll understand the car more, can predict the characteristic of the movement more since the system is so much more progressive.

I would go for the springs if you're planning to retain the OEM suspension, Birds option would be good as i'm sure they would have a great spring for UK roads.

But if you would like other ideas then consider the Bilstein B14 kit, Height adjustable and are on a medium setting from the Full Fat B16 kit with 10 setting, tried my friends car with it on, performs similar to birds kit, but it highlights the need for better body control as this kit really allows you to push the car better and you would start noticing more weaknesses.

Bilstein B16 kit aka PSS9/10 kit - no need to say anything but if you can buy the birds kit then you can afford this kit but might be over killed so the B14 would be a perfect kit to fit in the middle.

Tyre's
Same problem on our E92 cars, we all change to Non RFT and we get more grip and softer ride, better handling depending on what tyres you use.

If you want the ultimate grip then go for Michelin pilot super sports, try it and you never go other brands. I have it on my 450bhp /4xx torque 335i and it give great amount of traction even on start up. so with torque rich diesel cars, it would be great!!

Problem with the B14 kit is it's only available with a minimum of 30mm drop, which is too much, even the 10-15mm drop of my ACS springs has caused my car to scrape a bit where it didn't with standard suspension.

The B16 is available in a Komfort version which has a minimum of 10mm drop, it is the kit that NISFAN has.

[Watsey]

Thanks for the input Yoro. One clarification though, in case we've got a crossed wire : the "B3" I'm referring to are the Birds B3 suspension components (springs and/or full kit - they can be bought separately), not Bilstein B3 dampers. You're not happy with the Birds B3 full kit ?

[Watsey]

@Teaston : very surprised to hear you're getting rubbing using ACS springs, especially with ACS being a BMW specialist. Do you get this with regular driving, or only when the car is up to the roof with people and luggage ?

[teaston]

Originally Posted by Watsey

@Teaston : very surprised to hear you're getting rubbing using ACS springs, especially with ACS being a BMW specialist. Do you get this with regular driving, or only when the car is up to the roof with people and luggage ?

Not rubbing, scraping the underside of the car & front bumper on speed humps, curbs, driveways etc.

[Watsey]

@Teaston - sorry, I should have read your reply more carefully. Understood now. Will bear the ride height in mind.

[Tengocity]

Originally Posted by teaston

Not rubbing, scraping the underside of the car & front bumper on speed humps, curbs, driveways etc.

Do you have a front splitter teaston?

I don't at the moment and have never in 42k miles scraped the car. The front of my xdrive probably sits a little higher though.

[Nick the Greek]

Too much weight over the front Axel due to a diesel lump.

Sell up and get a petrol which is far more suited to "spirited" driving.

[dopper99]

Originally Posted by Nick the Greek

Too much weight over the front Axel due to a diesel lump.

Sell up and get a petrol which is far more suited to "spirited" driving.

Yes but with that weight loss of a petrol engine comes a loss of torque. Never a good thing.

[teaston]

Originally Posted by Tengocity

Do you have a front splitter teaston?

I don't at the moment and have never in 42k miles scraped the car. The front of my xdrive probably sits a little higher though.

No front splitter. I visit a lot of peoples houses in my job and i do a lot of parking so i'm maybe affected motpre than most would be.

Just yesterday I scraped the underside after my front wheels went over one of the sort of half cylinder shaped speed humps on a private road. I have scraped the front bumper on those kerbs at the end of some parking bays, and also on a couple of steep driveways.

Also these type of lanes usually cause multiple scrapage:

[Ice Man]

Originally Posted by teaston

No front splitter. I visit a lot of peoples houses in my job and i do a lot of parking so i'm maybe affected motpre than most would be.

Just yesterday I scraped the underside after my front wheels went over one of the sort of half cylinder shaped speed humps on a private road. I have scraped the front bumper on those kerbs at the end of some parking bays, and also on a couple of steep driveways.

Also these tycpe of lanes usually cause multiple scrapage:

For those not familar with the Norfolk area that is the a11 the main road into Norwich

[teaston]

Originally Posted by Ice Man

For those not familar with the Norfolk area that is the a11 the main road into Norwich

Actually the A11 is duelled all the way now!

The picture is of the A47!

[Wills2]

Originally Posted by Ice Man

For those not familar with the Norfolk area that is the a11 the main road into Norwich

Very funny.

[atomic335]

Like Tengocity I too have the ACS springs, Birds ARB's and MPSS.

As it stands at the moment I'm quite happy with the ride and its really about as good as its going to get (always a compromise between comfort and handling) without going for a full coilover like and key to that is one that’s been correctly developed on both a chassis dynamometer and on the road with the correct valve, bump, rebound and spring ratio. The ride is pretty good considering its essentially a mix of components which were never designed or tested to work together which is exactly the sort of thing you are paying for when you buy an Alpina for example as those they use different springs and ARB's to stock BMW along with reprogrammed adaptive dampers.

I think one the key decisions I made was to stay with the 18" wheels as these provide a more supple ride than the 19's and with the roads in and around W.Yorks trust me you want supple as I been to banana republics with better roads.

Another point you made was the brakes, again I too found these lacking, mine like Tengocity's are the MSport 370mm. I changed out the lines to the calipers to ones from HEL Performance and the fluid to Endless RF-650 (which is a higher viscocity than the low viscosity fluid recommended by BMW), I also changed out the pads (front & rear) for Project Mu HC+ pads. These changes made a welcome improvement.