[Bmoney2K4]

Hi all,

I would like to know which suspension part or parts are the best way to improve the suspension as it pertains to handling and steering on my base suspension 2015 BMW 528i. Recently, I have installed Bridgestone Driveguard Plus runflats which have made the steering and handling characteristics surprisingly worse than the Goodyear runflat LS 2 tires which were previously installed on my car.

Now, I am contemplating the best most and most efficient way to improve the characteristics listed above. Any information would sure help as I am searching for a good website to buy these parts from at the moment.

[Surly73]

If you don't have X-Drive you have more options for suspension/shocks, which is a plus.

First, I would get yourself mentally prepared. A 5 second scan of your post history points to E60s and E90s. Prepare to be let down by the F10 as a driver's car. (My history is E39, E46 and E90 myself) It is not an evolution E34 -> E39 -> E60. It is a "little 7" instead of a "big 3" and is built to satisfy different consumer demands than the older cars. If you've experienced the past models, the steering will never feel good in comparison.

You can go coilovers, or something like Bilstein B6 (but I would say there's a shortage of well thought out spring options to modestly lower and firm up, without the priority being low appearance - perhaps Dinan). This is one reason I chose coilovers - I can set ride height and dial out ridiculous looking rake that spring-makers may implement intentionally.

There's also a lot of back and forth on sway bar options. The H&R and Eibach kits are nearly identical, but in my personal experience the 30mm bar is a little large up front and leads to negative side effects due to insufficient independent action across the car (IMO).

None of this is necessarily cheap. If you have DHP, EDC, ARS etc... then you should actually be in pretty good shape already if it's turned up and working properly.

[M_Bimmer]

Originally Posted by Bmoney2K4

Hi all,

I would like to know which suspension part or parts are the best way to improve the suspension as it pertains to handling and steering on my base suspension 2015 BMW 528i. Recently, I have installed Bridgestone Driveguard Plus runflats which have made the steering and handling characteristics surprisingly worse than the Goodyear runflat LS 2 tires which were previously installed on my car.

Now, I am contemplating the best most and most efficient way to improve the characteristics listed above. Any information would sure help as I am searching for a good website to buy these parts from at the moment.

Wouldn't the easiest and cheapest thing to do, while your tires are still new enough, is to return back to Goodyear RFT's?

Not all RFT's are equal, and personally would place Bridgestone RFT at the bottom for "comfort" and "handling". Additionally their brand also have an unacceptable level of rolling noise after the break in period (if there is such a thing), IMHO.

[StradaRedlands]

Ditch the RFTs and get some Michelin Pilot All Season 4s.
The difference will be mind blowing!

[Thecastle]

I race my 550i xdrive F10, and run the stock suspension, I drive on Michelin Pilot Sport 4s on the street year round (there are better track tires). If you drive it right, its a real BMW underneath the softness and lean, and you can easily tripple or quadruple any posted corner speed limit, you're not at the limits until you can hear howling, and feel scrubbing.

Tires will make a bigger difference in your handling than any suspension mod. They are the only thing that contacts the pavement and their grip are what limits your handling, braking and acceleration. Changing dampers, springs, etc will not meaningfully improve handling, like a tire change will. Do not run all seasons or RFT, if you want good grip, run dedicated summer performance tires when weather allows. Their improvement will be a revelation.

Really when people say I want to improve "handling" what they really mean is feel/ride quality. They aren't actually trying to drive the car at its limits and improve their cornering speed. They just prefer the feeling of a stiffer riding car. Which actually can make for worse handling as too stiff suspension will cause the tires to leave contact with the pavement when crossing road imperfections/pot holes lowering your grip. For most people handling on the street means, confidence, wandering, feeling connected to the car so I'm not nervous driving at freeway speeds in a construction zone. Not I'm trying to get my lap times down by carrying 4 mph more through that 60mph corner that I'm trying to run at 129mph instead of 125.....

[ChiNorm]

I suggest getting the MSport sway bars as a first step to tighten the suspension. Good luck.

[smokinu454]

how many miles are on your car. Mine is at 93k and it feels much more planted after refreshing front and rear control arms/bushings. As ChiNorm mentioned, M sport sway bars are stiffer. I went with the H&R 30mm front sway bar, it is a little stiffer than the factory M sport sway bar.

[Bmoney2K4]

Originally Posted by smokinu454

how many miles are on your car. Mine is at 93k and it feels much more planted after refreshing front and rear control arms/bushings. As ChiNorm mentioned, M sport sway bars are stiffer. I went with the H&R 30mm front sway bar, it is a little stiffer than the factory M sport sway bar.

42,850 miles.

[smokinu454]

Originally Posted by Bmoney2K4

42,850 miles.

Not likely that you would have alot of worn out parts at that mileage but it is possible. I would certainly pry around and make sure that all of your bushings, ball joints, tie rod ends, etc are still good and tight. The best thing you can do for the car's handling is to make sure the suspension is still tight. After that I would ditch the run flats, upgrade sway bars, and see how you like it. Coilovers would be next IMO.