H&R springs still no good?

[killian665]

I’ve read plenty of older posts from 2010-2012 about the rear H&R springs being too weak. I also saw a lot of people saying they run them with no issues, so I don’t really know what to believe. I’ve found a lot of people on these forums tend to just regurgitate wrong information. Is the consensus still that they should be avoided or has H&R reworked them since then?

[SteveCT]

Interesting question, and probably worth a discussion with the Company to see if they made any changes in light of the criticisms from the E31 crowd...and if they did so, how one identifies the newer product from the old which presumably is important given the likely low velocity of dealer inventory turnover.

It would also be intersting to hear from anyone who has installed the rears recently to get fresh input...

[G8nightman]

I dont know if HR made any changes but i have them in my 850I and they are to low and soft I have replacement non HR waiting to go in.

[TedBobo]

I dont know if HR made any changes but i have them in my 850I and they are to low and soft I have replacement non HR waiting to go in.

Ditto!

[TxGR8White]

They were too soft then, and they are still too soft now.

[killian665]

Dang, that sucks. I guess I’ll have to source something else.

[IJustDrive]

I ran them on my prior 850. They sit lower than say the Eibachs. They stance looks nice if you like it a little lower. When combined with the Bilstiens (because these are so stiff) they provided an acceptable ride. The balance might be a little off, but unless your going to track your car, I think they are fine. You need to look at your spring and shock combination and usage before deciding which is right for you. Many are also using the H&R front in combination with something else in the rear (cut OEM or MTech CSI)

[killian665]

Yeah I’m looking at the KAW Springs with bilstein sports now

[m6bigdog]

I’ve read plenty of older posts from 2010-2012 about the rear H&R springs being too weak. I also saw a lot of people saying they run them with no issues, so I don’t really know what to believe. I’ve found a lot of people on these forums tend to just regurgitate wrong information. Is the consensus still that they should be avoided or has H&R reworked them since then?

As most are aware this is a topic that goes back to the RoadFly days and I have weighed in on this topic since I upgraded my 850 suspension in 2005.
I have done the research, home work and the H&R could care less what the E31 owner thinks about their springs, I know because I talked to them in 2005.
Bilstein shocks are an issue because they are a High-Pressure gas shock which increases the ride height, something we are trying to reduce, the actual shock rates may not be compatible with the springs installed and Bilstein compression rates typically cause a very harsh ride. Hence those that are most happy with Bilsteins have had them re-valved.

The aftermarket spring sets (H&R, Eibach, etc.) are problematic for the E31.
The actual reason for their failing of a weak rear spring is IMHO due to the equation used to calculate the installed spring rate for the E31's rear multi-link suspension.
The typical coil-over suspension (front of E31, F&R E32, E34) is a simple calculation with the installed spring rate being equal to over 90% of the actual spring rate.
However, the E31 rear suspension requires the mathematical squaring of the springs installed suspension ratio of .60, therefore the calculated/measured installed spring rate is a measly 36% of the actual spring rate.
I would suggest that BMW offers the stock, Euro M-Sport and CSi spring combination that provides reliable/predictable rates for best performance.
If you want something lower in the front? then use the H&R front with the BMW Euro M-Sport rear spring.
If you want a stiffer ride than the BMW CSi springs offer? then the Eibach front with a custom cut Eibach stock spring (thelongride post: http://www.bimmerforums.com/forum/sh...imited-edition).
I suggest you get the best BMW or anyone has to offer by using the Euro M-sport Springs, rear M-Sport shocks with a Koni front adjustable cartridge installed in the OE front strut.
See Hypers Post: https://www.bimmerforums.com/forum/showthread.php?1995992-Koni-front-inserts-revisited&highlight=Hyper+Koni
If you want to study what this is all about please review the Pitch/Bounch motion location center information I put together in 2013.

[killian665]

Wow what an enormous pain in the ass that looks like

[dragon850]

Dinan stage 3 springs + TRW shocks = very very happy.

[Fatandre]

Running TRW plus eibach now. Happy

Refurbishing CSI springs that will go in and should make me super happy

[killian665]

Coming across the m sport springs is next to impossible. I wish someone just made adjustable coilovers.

[cartoonz]

All the spring info you need is right here...

http://mwrench.com/Whitepapers/Mwren...ing%20Dyno.pdf

[killian665]

Right but all that was done 11 years ago. Was just asking if anything had changed. I’d seen so many bad things said about the H&Rs I thought maybe there would have been a change by now.

[mikae31]

Running TRW plus eibach now. Happy

Refurbishing CSI springs that will go in and should make me super happy

How can you refurbish springs ? They are, what they are.

[Fatandre]

Just sand them and paint

[tangcla]

Coming across the m sport springs is next to impossible.

I may have a set to sell soon...
but I'm a few oceans away.

[m6bigdog]

Coming across the m sport springs is next to impossible. I wish someone just made adjustable coilovers.

Adjustable coilovers do nothing to solve the Pitch/Bounce motion center location problem caused by a set of springs with a mismatch of the front & rear spring rates.
Having the wrong front to rear spring rate ratio is like having a stock spring on one front wheel and an H&R spring on the opposite front wheel. So then, you just use adjustable coilover strut to correct the ride height between the two sides.
Sport shocks nor swaybars help either.

Yes, you probably can't purchase M-Sport springs from the BMW Dealer as they are in the BMW Euro parts Catalog, however that I'm aware ECS Tunning can get them for you:
Front M-Sport springs p/n: 31 33 1 138 735
Rear M-Sport springs p/n: 33 53 1 138 738
Rear M-Sport shock absorber: 33 52 1 137 474, or option CSi rear shock with Koni Front strut cartridge installed.
Rear CSi shock absorber: 33 52 2 227 258
https://www.ecstuning.com/Search/Sit..._53_1_138_738/

You could also check Schmiedmann. They shipped me Euro parts I could not get anywhere in the US.
https://www.schmiedmann.com/

[lloydsss]

I have a set of rear eibachs and bilsteins available
less than a 1000 miles
i put my EDS BACK ON

[killian665]

Yeah I’ve ordered a bunch of things from Schmiedman, most of it 6 speed parts. My problem with the available spring options is that they still sit really high but I don’t want to hack up a set of CSI springs or something rare like that to get the height I desire. I wish air suspension wasn’t so expensive lol.

And by wanting adjustable coilovers I meant just some with proper spring rates that I can adjust the height of. My E39 I was able to get any spring rate I wanted. The suspension on these 8s isn’t too dissimilar from an E36 I don’t see why there isn’t something like that available yet. Proper spring rates with an adjustable perch in the rear and the front is like any other cartridge set up.

Also I’ve seen a lot of people suggest getting the rear CSI bump stops too for any kind of lowering spring, I’m assuming that’s because the stock one is too tall or something for aftermarket springs?

[killian665]

What if I had my stock springs shipped off to someone like Swift that makes custom springs and just had them make me some that gave a 1 1/2 inch ride height drop and were 30-50% stiffer than what I have but within the same front to rear ratio so that way it’s still a balanced for the 8 just stiffer and lower?

Like measure what they are for the front, new fronts be 30% more than stock and do the same for the rear. No change in front to rear ratio just stiffer.