neilv

I need an alignment and with my mileage I'm planning on doing some suspension upgrades while I'm at it.

I know the M5 Integral link is a direct swap (to my awd E61)

So it the upper guide link although ECS shows a build date difference:

-Looks to be for both sides and up to 09/2006 build date for M5's https://www.ecstuning.com/b-genuine-...h/33326779820/

-Looks to be side specific and from 08/2006 build date for M5's https://www.ecstuning.com/b-genuine-...t/33322283772/
and https://www.ecstuning.com/b-genuine-...t/33322283771/

These will be going on my 07/2006 build date car; does it matter for me at all?

Also I'm looking to see if anyone has put factory sport springs on the front of the xi cars (I know this can be done with E90s by switching to the rwd top hat as well) an does anyone know the letter for the spring codes on sport springs; My xi has "F1".

neilv

Looks like the #820 M5 arm has a M10 nut and conical seat where as the 771/772 arms are M12, ball seat and left/right specific.

Also it fits the Z8s and some other cars plus the M6 up to 06/2006 and M5 up to 09/2006.

I just wonder if the rest of the E60s had the same split or are we just 1 style(especially since my build date (07/2006) is right in the damn middle.

inline6xi

interesting project, please post some pictures of the build!

p.s. that is an expensive link :O

neilv

I'm using this as more of an info dump.

so the front Xi lower spring pad is the same part number as the E90/E82/E84 and E89 cars. (bottom of the spring should be the same)

The XI upper spring pad/perch have the same part number as the I E60, I6 E39s and E46(all) (Top of the spring should be the same as those)

I have also seen a few E46 guys use the Supreme power drop perches(Designed for E90s) to drop the front. (SP drop hats fit like stock but drop 10/15mm)

-If I wanted to keep my stock springs I could buy the SP drop perches and use the E61 air system to drop it to match
-Going by that I could also use E90 front springs(sport package) but Id have to try to figure out E60 spring rates to match the E60 and try them out/check ride height.
-The E60 RWD and AWD springs share the same parts/dimensions at the top but change where it mounts to the strut (I wonder how much different they really are).

E90 AWD cars can use RWD springs if they change the upper parts to RWD as well and they have the same ride height as they would on the rwd chassis. Just hoping somehow inverse works here too

inline6xi

Interesting info, keep it up! I just bought the hr lowering springs and new stock Sachs shocks. Looking forward to installing.

Side note, but xi suspension related, I'm bummed at how expensive the front bump stops are! Anyone know of a replacement to stock that is cheaper? Rein only makes rears 😞

neilv

I have read that the H&R are a very rough ride. I enjoy sporty and firm but I am curious to how they compare to sayyyy an E90 w/sport package springs. Coilovers arnt an option for me (winter car + I'm keeping the rear air bags) and Eibachs arnt easily available in NA.

E60 sport springs are vastly different in the bottom so those arnt usable. Athough I found out the code #'s:

E60xi : "F#"
E60i non-Sport: "A#"
E60i Sport: "B#"
E60i M-Sport: "M#"

So I'm turning my attention to an E90 ZSP front spring swap.The bottom of the spring is identical and the top of the spring will work the same; So it is up to spring rate and ride height. Nothing can be softer than an xi/non-sport (its truly a mushy/unpredictable ride) so I expect the E90 sport springs to be stiffer. The E60 xi springs have 5 coils whereas the e90-sport has 5.5; closeish. Ill have to found out rough lengths of each spring unloaded and the coil thickness to get a good estimate.

Also I might have some adjustability with ride height. The e90 sport springs came with the same (or damn near close) spring rates but the lengths of springs were adjusted to compensate for weight (turbo/non-turbo, sedan/coupe/convertible/wagon and auto manual) so a different number might change slightly. I'll see if I can grab an E90 non-turbo sport spring "D5" at a wrecking yard; the weight is very similar to a non-turbo E60 so spring rates should work relatively well.

I also have some adjustment to the ride height from there. SP drop perches will lower 12mm and eibach pro-kit E90 springs will lower ~15mm from the stock sport while keeping spring rate similar. For the other way the E30 top perches will raise it about 12mm so I have some wiggle room plus the fine adjustments of going up or down in the spring number. Should be interesting

neilv

Taking apart a stock rear hub(for 550 brake swap) looks like the early M5 control arm (33 32 6 779 820) is a direct swap to the normal E60/E61 line up. Its an upgrade due to the bushing becoming a spherical bearing(less deflection). I'll be doing those at some point on later down the road. Lemforder makes them as well as BMW but they are 1/4 the price for the same thing.

Springs I am looking at the D4(E90 N52 Manual Sport) and D5(E90 N52 Auto Sport) springs for the front. The D5 will be easier to come by as they are auto but Im not sure exactly how either will sit. I have a Manual car but I also have extra weight on the chassis from the Panorama roof. Only time will tell.

colriem

Did you end up trying the E90 springs?