Help ! Confused about E86 Suspension options

[NickDE]

I have been trawling around the forum, but have just succeeded in getting myself more confused ! :?

I am planning to make some changes to the suspension on my E86 Sport. It has the M Sport Suspension, and is now on 70000 miles with what look like original springs and shockers. On the whole I am happy with it. Handling is fine for me, but I don't like the way it crashes through potholes etc
So my aims are:
- Improve the ride on rough roads
- Keep handling as is/improve a bit on smooth roads
- Swap out rear springs before one snaps on me
- Keep ride height as is
- Not spend more than I have to
I first thought Bilstein/Eibach B12 kit, but don't want to lower the car. Then thought Bilstein B6, but not sure about springs to use. I've seen a few people recommend Suplex springs, but not sure what shocks to use. Can I leave the original front springs on and only swap out the back ones to avoid the snapping issue ? Any suggestions on how to proceed welcomed

Also, where is the best place to buy the stuff from ? And are there any bushes etc that are no-brainer replacements when in there anyway ?

 

[Buckz]

KWs probably, you can adjust the height to sit a bit higher/stock height and then adjust the damping too.

I've got suplex springs in mine, they're standard everything so I can't see how they'd make the ride any better? maybe less prone to snapping but that's about it.

 

[Scooba_Steve]

Suplex with B4 shocks is what seems to fit your bill. No guarantee they springs won't snap but can't be worse than OE.

KWs will give you a huge range of options but I am guessing you don't want to be spending £1k+

 

[highway1]

Suplex with B4 shocks is what seems to fit your bill. No guarantee they springs won't snap but can't be worse than OE.

KWs will give you a huge range of options but I am guessing you don't want to be spending £1k+

The Suplex springs and B4 shocks are what I had fitted to my coupe , a few months back.

I am very pleased with them- firm but compliant and you don't feel like you're going to be bounced straight off a bumpy road! I had SE suspension on my coupe so I replaced with M-sport equivalent springs and The B4 are considered to be a superior M-sport equivalent.

I was surprised how tired my original shocks at 64,000, were. The front drivers side was completely shot!!

I also had new droplinks and top mounts all-round as well as poly anti-rool bar bushes f&r and a proper 4 wheel alignment with someone who knows what they're doing.

The results are great!

 

[NickDE]

So would a sensible choice be:
Suplex 06231 springs on the rear
Original M Sport springs on the front (cos they seem to do what I want and I can save money by not replacing)
Bilstein B4's all around.

Or should I go B6 ? Which will give good handling without crashing through the potholes ?

 

[Scooba_Steve]

I personally wouldn't keep the originals on the front.
Shocks are not going to stop crashing by themselves.
If you are doing the front shocks you're not going to save much by not doing the springs, and you should also consider replacing bushings. While they're out top mounts would be silly not to replace.
If you're going to do it on the mega cheap then better to not bother and save until a proper job can be done, otherwise just adds future costs.

 

[NickDE]

I personally wouldn't keep the originals on the front.
Shocks are not going to stop crashing by themselves.
If you are doing the front shocks you're not going to save much by not doing the springs, and you should also consider replacing bushings. While they're out top mounts would be silly not to replace.
If you're going to do it on the mega cheap then better to not bother and save until a proper job can be done, otherwise just adds future costs.

I'm happy to spent the money to get the results I want. I just don't want to spend cash on kit that doesn't really make a difference to me but just earns bragging rights.
Bushes and mounts - just buy the relevant bits from BMW (who usually give me a discount) ?
Which springs would you recommend ? A matching pair of front Suplex's ?

 

[Scooba_Steve]

Ok, that's a different aim then. IMHO the B12 is more compliant than stock but it's still a firm ride. Unless you go for coilovers to adjust the ride to perfectly suit, you're going to have to compromise.
Whatever springs you get, replace them all, it's minimal cost if you're doing the shocks. I can't really make a recommendation as I've only experienced stock and Eibach.
BMW are cheap for things like ARB bushings, Lemforder/Meyle are OE quality and about half the cost vs. BMW. It's worth doing your front control arms, at a minimum the brake reaction/lollipops on the back. Drop links are cheap and worth doing, also budget for tie rods in case you need them.
RTABs made a huge difference to me, big debate over OE/OE+limiters/Poly, but whatever you get will be better.

If you're not going to see a track then I don't really see the point in going for B6/B8 type shocks. If you really are obsessive about the ride then you'll need coilovers.

 

[NickDE]

BMW are cheap for things like ARB bushings, Lemforder/Meyle are OE quality and about half the cost vs. BMW. It's worth doing your front control arms, at a minimum the brake reaction/lollipops on the back. Drop links are cheap and worth doing, also budget for tie rods in case you need them.
RTABs made a huge difference to me, big debate over OE/OE+limiters/Poly, but whatever you get will be better.

It has had some bushes etc done in the last 20000 miles by the last owner. I'll have a look when I start pulling everything apart and replace anything dodgy looking as I go.

I think I am going to go for a Suplex/B4 combination. Unless anyone has a better suggestion. And then spend the money I save on B6's on a pair of E46 comfy seats !

ps thanks for the CC instructions. I ordered the parts this afternoon.

 

[Scooba_Steve]

It won't be any worse than OE and seems to suit your needs. Bushings are not much if you DIY and make the car feel a lot tighter.

 

[NickDE]

Just back from a first short drive, after fitting Suplex springs and Bilstein B4s all round. Together with new drilled discs and pads, plus 15/20mm spacers. Plus new top mounts all round and rear drop links. So far I am very happy. The ride over rough roads and potholes is totally transformed, and is so much more pleasant. Not sure about handling yet, as it was just a short drive, 4-wheel alignment is not done yet and brakes still bedding in.
But it seems like I met my aims:
- Improve the ride on rough roads
- Keep handling as is/improve a bit on smooth roads
- Swap out rear springs before one snaps on me
- Keep ride height as is
- Not spend more than I have to
Apart from the spring snapping, as one turned out to have already snapped. And the money saved is going into a set of M3 seats !

 

[RyanB88]

Look into e46 suspension as a cheaper way of getting the same results. I've been advised they fit

 

[highway1]

Just back from a first short drive, after fitting Suplex springs and Bilstein B4s all round. Together with new drilled discs and pads, plus 15/20mm spacers. Plus new top mounts all round and rear drop links. So far I am very happy. The ride over rough roads and potholes is totally transformed, and is so much more pleasant. Not sure about handling yet, as it was just a short drive, 4-wheel alignment is not done yet and brakes still bedding in.
But it seems like I met my aims:
- Improve the ride on rough roads
- Keep handling as is/improve a bit on smooth roads
- Swap out rear springs before one snaps on me
- Keep ride height as is
- Not spend more than I have to
Apart from the spring snapping, as one turned out to have already snapped. And the money saved is going into a set of M3 seats !
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Good to hear you're pleased with results! Just make sure that when you get the alignment done, make sure its with someone who knows what they're doing and doesn't just put in standard BMW settings which are not the best.

I had my alignment done by a chap in Bristol who only does wheel allignments and knows the Z4 chassis very well.

I had Suplex springs and Bilstein B4 as well (plus poly bushes f&r anti roll bar) and after a fast road alignment, there was a big improvement again!

 

[NickDE]

Agree on the alignment. I had it done by a guy who knows his stuff on performance cars, plus has just spent about 60K on state of the art alignment equipment.
Suspension is working well for me - was good on the track, plus deals well with my 2 hour commute up the A1 (boring) or down the A68 (rollercoaster)