[el_couzin]

Originally Posted by anh3

front-MB, rear-MC, with stock dampers and those are my only mods on suspension. Everything else is stock. I would also have gone with better dampers than stock if I have to do it again, though I don't know how much 'better', but the F80 spring is definitely a much improved mod on its own for the Xdrive chasis. Also more noticeable improvement is the bloaty feel, body-roll in corners is much less noticeable, more control.

Could you post pics of before and after install?

there's a set of MB/MC for sale in my area and I'm not sure if I should or not because I drive my car all year long (canadian winter)

I have a xdrive 335i with adaptive suspension

[johnung]

Originally Posted by el_couzin

Could you post pics of before and after install?

there's a set of MB/MC for sale in my area and I'm not sure if I should or not because I drive my car all year long (canadian winter)

I have a xdrive 335i with adaptive suspension

I've been very happy with my 335ix on Eibach springs. They are about 10% stiffer for more control without the harshness of other springs like H&R that can be 30% stiffer. Eibachs lowered me front 0.8", rear 0.6" which has been no issue in snow.

[el_couzin]

Originally Posted by johnung

I've been very happy with my 335ix on Eibach springs. They are about 10% stiffer for more control without the harshness of other springs like H&R that can be 30% stiffer. Eibachs lowered me front 0.8", rear 0.6" which has been no issue in snow.

thanks for that but my concern is really about the MB/MC combo. I've finally purchased the set of spring but I don't even know if I'll install them on my car. Not sure but I think I found a leak on my front suspension. I might invest in a set of EDC bilstein B4. F80/F82 springs with edc B4 should be a great upgrade without being too low.

[anh3]

Originally Posted by el_couzin

Could you post pics of before and after install?

there's a set of MB/MC for sale in my area and I'm not sure if I should or not because I drive my car all year long (canadian winter)

I have a xdrive 335i with adaptive suspension

all the pics above was after, I don't have any before pics. I have not driven mine in deep snow yet (more than 3" or 4"), I do drive my year round. Here is some unofficial ground clearance measurements:

front ~6", rear ~7". Sorry for the sidewise rotation and dirt, just got back from a camping trip! Measurements taken relative to side skirt, front and rear wheel well, driver side.

[el_couzin]

Originally Posted by anh3

all the pics above was after, I don't have any before pics. I have not driven mine in deep snow yet (more than 3" or 4"), I do drive my year round. Here is some unofficial ground clearance measurements:

front ~6", rear ~7". Sorry for the sidewise rotation and dirt, just got back from a camping trip! Measurements taken relative to side skirt, front and rear wheel well, driver side.

Thanks for that, I'll be able to compare with my stock suspension

[Ausmurry]

Interesting thread, I was looking to run the f80 swift R springs on my f30 with EDC. (Car will be used for autox and daily). Im wondering how aftermarket f8x springs will works on an 340i.

[f8xguy]

Hi

I am new to this site so apologies for my ignorance.

May I ask the certainty and source of this information as I am searching for OEM f80 CS springs.

Thank you for the excellent information and help.

Originally Posted by FaRKle!

There seems to be more interest now on retrofitting F8x springs to F3x cars, but a lot of "unknowns" in the community about them. I hope to make things more transparent on the F8x springs option.

Introduction/Framework

The F8x cars (F80/82/83) have two "suspensions/classes" of springs. They are the "base" suspension and "ZCP/competition pack" suspension. Within each class of springs are two more sets of springs that are tied to how the car was optioned. The front spring selection is tied to is the transmission (DCT vs manual) and for the rear spring it's the roof (sunroof or no sunroof). For the F83 there's only one rear option per spring class.

Since the spring config depends on the weight, the higher weight option springs have a slightly higher spring rate, by about 2-3%. For example DCT front springs are slightly stiffer than manual transmission fronts, and sunroof rear springs are slightly stiffer than plain roof rears.

The F80/82 use the same springs, and the F83 has a whole different set due to its much higher weight.

The differences between the classes of springs (base vs ZCP) are mainly spring rate, where the ZCP springs are stiffer by about 10-15%. Additionally, the ZCP rear springs are progressive, while the base suspension springs are linear (like F3x springs). Both base suspension and ZCP springs give the same ride height.


Spring Identifier Codes

BMW springs can be identified by the two letter code on the barcode sticker on each spring. Below are the configs and barcode identifiers.

Front springs:

• F80/82 Manual: MA
• F80/82 DCT: MB
• F80/82 ZCP Manual: MP
• F80/82 ZCP DCT: MQ
• F83 Manual: MG
• F83 DCT: MH
• F83 ZCP Manual: MV
• F83 ZCP DCT: MW

Rear springs:

• F80/82 Plain Roof: MC
• F80/82 Sunroof: MD
• F80/82 ZCP Plain Roof: MR
• F80/82 ZCP Sunroof: MS
• F83: MI
• F83 ZCP: MX

F3x Applications

So how does this translate to the F3x series of cars? Well, it's important to keep in mind the design and weight of the F8x cars. For example, putting F8x front springs on a 4cyl front RWD F3x isn't a great idea. The front end is much lighter, and you may end up gaining ride height. Like-wise, putting F80/82 rear springs on an F31 or F34 with significantly higher rear weight is likely going to put you too low, or lower your ride frequency too low compared to the front. F8x cars have lower ground clearance (4.7" vs ~5-5.7" for most F3x), so you'll want to consider that as well if thinking about ride height.

Below are my thoughts on how F8x springs might pair with various F3x cars (speculation) based upon what I know about these vehicles' weights and spring rates.

4cyl RWD F30/32/36
F8x front springs probably aren't a good idea. The lighter front end means you may gain ride height. Rear F80/82 springs might be fine and slightly lower.

I don't think any of these cars should go higher than F80/82 base suspension spring rates because the damper tuning isn't likely strong enough for ZCP rates.

6cyl RWD F30/32/36
F80/82 springs should give you an increase in front spring rate and a bit lower. I wouldn't expect a lot lower though, at maybe 0.6" or less. F80/82 rear springs should do similar as the front.

F80/82 base suspension spring rates should be fine with these dampers. ZCP spring rates are probably close to the edge of what the dampers can acceptably do (EDC has a more head room though, even more so with shockware).

4cyl xDrive F3x
F80/82 front springs should work with the extra weight of the transfer case up front, but I wouldn't expect much lowering (F30/31/32/36). Look for springs from manual transmission F80/82 cars to avoid ride height gain. I expect the same ride height as stock to about 0.5" of drop. F34s should check how close their front weight is to the other F3x cars to see if it'll lower more (likely).

F30/32 should be able to use F80/82 rears fine for ride height. F36 is a bit heavier in the back, but should still be OK height-wise. F31/34 shouldn't use F80/82 rears without spacers/shims, and I don't recommend ZCP rears since the progressive travel isn't well matched. F83 rear springs might work for the F31/34, although you'd need to check the weight (F31 might not really lower with F83 rears since the F83 is heavier in the back).

F30/31 base suspension dampers shouldn't be paired with more than F80/82 springs, and those are probably right on the line. EDC dampers should be able to use F80/82 base suspension rates fine and likely ZCP too.

F32/36 all suspensions' dampers should be able to use F80/82 base suspension rates. Front ZCP rates are probably fine on both, but F32 rear dampers might not handle ZCP rear springs all that well.

6cyl xDrive F3x
F80/82 base suspension front springs will be close to stock spring rates, so might not do much for handling, but would lower (and probably a bit more than for 6cyl RWD cars). F83 front springs will probably lower a bit (like the F80/82 springs for 6cyl RWD cars) and be stiffer.

For the rear springs, F80/82 springs should pair the same on F30/32/36 as the RWD models. F34s, the same as in the 4cyl xdrive section probably applies.

Everything except the F30 base suspension dampers should handle F80/82 base suspension spring rates. For ZCP rates I think F32/36 dampers and F30 EDC dampers should handle the fronts acceptably, and for the rears F30 EDC and F36 should be OK. F32 rears probably shouldn't use ZCP rear springs.


What I've Tried

Here are the springs I've tried on my own vehicle (F31):

• F80/82 DCT front
• F80/82 ZCP Manual front
• F80/82 ZCP DCT front
• F80/82 ZCP Plain Roof rear

The DCT front springs were higher than I liked (basically stock/OE height). The ZCP manual front spring is what I'm using right now. It's not much lower than stock, but gives me the front ride frequency I want and barely clears parking blocks.

In the rear the ZCP progressive spring wasn't very good for my setup. The initial rate ride frequency was too low, but the final rate was good. Because of the progressive nature and how mismatched the progressive travel was to my chassis it felt like I was dragging the rear end when doing hard cornering.

Forum member bariaga1 purchased a set of F80/82 DCT ZCP springs from me for his F30 335i M-Sport. They dropped his ride height 1/4" in the front, and rear (note that the M-sport already sits lower than base suspension cars). When we went for a test drive after installing the springs the ride felt pretty good, and I didn't feel the dragging sensation as with my car. Last I heard he was pleased with how much more nimble the car felt.


Other Springs

From the data/spec sheets I've seen it looks like Eibach's F3x front springs replicate F80/82 spring rates (within 5%). Eibach's 6cyl RWD/4cyl xDrive and 4cyl RWD front springs have about the same rate as F80/82 base suspension front springs, and Eibach's 6cyl xDrive front springs are about the same rate as ZCP fronts. The Eibach springs will lower the car more than the F80/82 springs though, with the exception of the "tall" 6cyl xDrive front spring (F11-20-031-06-VA), which should have pretty much the same height as an F80/82 DCT spring. Eibach has a spring rate tolerance of +/- 5%, and BMW's is tighter than that.


Please don't PM me about springs for your car, 1) so we can keep the info public to help others and 2) I'm not your personal spring consultant, unless you're buying one of the sets I have for sale , haha.

[fijigabe0]

I can confirm that the F80 springs do work on the F30. I am using the MQ/MS spring combo with Bilstein B6 springs and they feel great. Unfortunately, there isn't much of a drop, at all, but I attribute that to the heightened spring perch on the Bilstein shocks, not the springs, themselves (which probably drop the car a slight amount, to offset the increased height. I would say that this combo keeps the car at stock ride height.

[NigelC]

I have been trying to figure out F30/31 BMW 2 letter spring codes on the little bar coded labels particularly for the rear.

It seems that X-Drives codes start with E
I have seen EC,ED,EF, and EH, the EH ones are from my 330d touring with sunroof so I suspect the first letter may be length and the second letter designates increasing weight.

M Sport springs seem to start with G but I have found a few anomalies as GD seems widely used but I have also spotted GD springs advertised from 4 Cyl cars supposedly SE spec as well as M Sport.

Its a shame that there doesn't appear to be a decode or application chart available.

[smeard]

Originally Posted by F80AlpineWeiss

So I have a set of F8x H&R Sport Springs from my M3 that sold a few weeks ago.

I have a F30 340i xDrive now. What's the consensus on the F80 lowering springs working on my 340?

This^

recently received a free project F30 6MT from my brother, wanting to turn this into my little track beater (needs a lot of love, don't have to worry about wrecking). Found a set of H&R Reds for cheap meant for F80/F82 wondering if I can pair this with a competent strut setup (possibly Bilstein B8, B14).