Springs help, please.

Stu23 · Post by **Stu23** » Thu Jan 16, 2020 10:59 am

Hi All. My car is an E85, 04, 3.0i SE Automatic, 91k miles.

I have understood from perusing various posts here that these came standard with MSport suspension, i.e. 15mm drop. Is this correct, firstly?

I need to buy new shocks all round and would like to replace all four springs while I'm in there, if only to know what's on it. After much thought, I've decided not to lower the car further. Although I'd like the reported improved ride of the Eibach Pro kit, I don't want to deal with less ground clearance. The roads round here are pretty awful and I deal with a lot of speed bumps!

I will be using OE grade replacement shocks, probably Bilstein B4 if I can get them. Will also replace top mounts etc. while I'm in there.

So, simple question... which springs are a like for like replacement for the OE (MSport?) kit on this car? Is there anything which is same ride height, but improved quality, like the Eibachs but without the drop?

Thanks!

Stu23 · Post by **Stu23** » Thu Jan 16, 2020 11:22 am

OK. Apologies for answering my own question, but after 2 days of googling I found two alternatives about 10 minutes after posting above!

Anyone got any comments on the two options below, and any reason to pay more for the Suplex ones?

: springs.jpg (57.75 KiB) Viewed 1205 times

eddiemunster · Post by **eddiemunster** » Thu Jan 16, 2020 12:04 pm

Stu23 wrote: ↑Thu Jan 16, 2020 11:22 am Anyone got any comments on the two options below, and any reason to pay more for the Suplex ones?

Yes, they're not equal, and in honesty I wouldn't waste money on any of these. Branded springs use better quality materials, coating, design, manufacture, cheap copies like these rarely do any of that, they're cheap because they're cheap.

It's your choice, but when Eibach can make a set for £140, why on earth would anyone bother with these?

Stu23 · Post by **Stu23** » Thu Jan 16, 2020 12:24 pm

They don't seem cheap to me. Same price or more than Eibach.

So what's the equivalent of Eibach quality in standard (MSport) height?

What's the feeling of those using the Eibachs in terms of "roadability"? Clearance over bumps etc.? I'm not interested in track performance, just want it to ride and handle nicely and be everyday useable on what passes for roads these days.

baconJazz · Post by **baconJazz** » Thu Jan 16, 2020 2:29 pm

I recently read a magazine article (maybe EVO ?) that had an interview with one of the original design engineers of the e86. He stated that lowering the ride height was a bad idea as the car was already set up perfectly and to lower it would have a negative effect on the handling. He did however say that if you wanted to do any modifications to the suspension he would recommend the Bilstein shocks and springs.

Stu23 · Post by **Stu23** » Sat Jan 18, 2020 12:12 am

Oh well, the best laid plans...

Have now bought and paid for a set of Eibach springs (from a forum member, new in box) and a set of B4s from Autodoc, along with top mounts etc.

So much for not lowering the car, but at least I know that it should all work together!

Timmyboybunter · Post by **Timmyboybunter** » Sat Jan 18, 2020 12:13 pm

Fyi, Suplex are a very popular brand on these forums when swapping out the useless OE springs. I used them when doing the rears on mine, were a perfect like for like change.

Stu23 · Post by **Stu23** » Sat Jan 18, 2020 12:56 pm

Thanks. Got a good deal on the Eibach pro kit and couldn't resist. I may fit the thicker spring seats so they don't drop the full 15mm.

saj77 · Post by **saj77** » Sat Jan 18, 2020 1:04 pm

I think you have made the correct decision. I fitted the pro kit and B4s and it’s transformed the car - (from original shocks that had done 88k miles).
I think you’ll be ok with the extra drop

Don’t forget to get 4 wheel alignment done. I went for M settings when I got it aligned on my non M roadster after doing lots of research on here, as it seemed to be the best option.

Stu23 · Post by **Stu23** » Sat Jan 18, 2020 6:05 pm

Thanks for that... will do!

Stu23 · Post by **Stu23** » Mon Jan 20, 2020 4:35 pm

In order to try and stick with my original decision as nearly as possible, I have now ordered some thicker spring caps front and rear to lose some of the drop from the springs. Part numbers are 31331135589 and 33531136387 if interested.

From my calculations, these should raise car by a theoretical 7mm at front and 8mm at back thus leaving the car just 7 or 8 mm lower than the MSport settings. I'll confirm with some before and after measurements. I'd guess given my current springs are 91000 miles old and quite possibly broken, it might end up in pretty much the same place as it is now

Stu23 · Post by **Stu23** » Fri Jan 31, 2020 9:23 am

So to wrap this up for anybody looking, I had the B4s and Eibachs fitted yesterday with all new top mounts, rubbers etc. The thicker 10mm spring caps were used front and rear, to keep the car somewhere near M Sport height.

Not at all sure what was in it...the shocks were clearly knackered whatever they were, but the springs all looked relatively new with shiny powdercoat under the dirt... a couple of them had what may have been BMW part labels on, I'll investigate later. If they were standard parts, I'd guess not 16 years old... and certainly not broken! I've kept the springs, dumped the rest. One of the front top mounts was torn, everything else looked OK.

I haven't measured it yet, but at the moment the car feels slightly higher if anything, but either way there's little in it. It seems to still be settling after 30 miles or so; the alignment was checked yesterday and will go back for final check next week. Somehow or other, even standing still, it seems firmer and more controlled.

Verdict: The driving experience is completely changed; it's much more composed, goes where it's pointed and is nowhere near as crashy over bumps and potholes. Rides softer over speed bumps, and no clearance problems. The car will comfortably drive faster and easier than it did down any road and I'm very happy with the results. It's exactly what I was aiming for and the advice found in these pages was all good.

Having said that, while the car is much better, the driving experience is far less alive... before it was a real go-kart, bouncing from bump to bump and alive in my hands, largely because it was bump steering all over the place. It was an interactive experience to drive before, now it's more of a 3 series in disguise! Knowing what I know now, I may have gone with the B12 kit and the thinner spring caps for a bit more spice and feedback at the expense of comfort. Anyway I didn't, and I shall learn to love the easier to live with - I'm sure the Mrs will prefer it this way

On a completely different note, had a great haul last night. Local guy advertised on FB that he was breaking a z4... picked up excellent replacements for all the sun damaged rubbers on mine, plus a headlight washer nozzle and a couple of other useful bits in good condition. About £400 worth of genuine BMW spares... for £20! Will be popping back today... I've thought of a couple more bits I need!

baconJazz · Post by **baconJazz** » Fri Jan 31, 2020 2:04 pm

The B4's are designed as a direct replacement for the M sport OEM shocks. The B6's are also OEM ride height but are the "Sportier" version . The B8's are the same Sport version as the B6's but ride lower. I'm going for the 6's with my current OEM springs which are fine. This is what Keith Bird technical directer of BMW tuning recommends

Stu23 · Post by **Stu23** » Fri Jan 31, 2020 4:51 pm

Just been round with a tape measure. It’s not sitting level, but is in the same place it was before. It’s dropped around 10mm on each corner, as expected. 100% happy.

Stu23 · Post by **Stu23** » Tue Feb 04, 2020 11:02 am

Having lived with the thicker caps, Eibach + B4 set up for a few days and got used to it, I’ve revised my earlier opinion. It’s great, but definitely firm enough. Wouldn’t want it any firmer, lower or sportier. Handles superbly and rides better than before. A good road use compromise.

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