[YODI]

Originally Posted by alohasurftoad

what tire sizes are you using?

265.35.19 and 235.40.19

[alohasurftoad]

Originally Posted by YODI

265.35.19 and 235.40.19

hmmm...imo, that is the best size combo for 437M because versus OEM, it's slightly larger diameter and width fills out the gap nicely. On F3/4 x-drives with 6-cyl engines, the 5-22 lowering usually looks spot on. 5-22 gaps are usually perfect especially with 235/40+265/35 on 437M. I wonder if the lighter weight of the 330dx is causing greater gaps on yours.

I wouldn't do H&R with stock dampers as it will cause an oversprung condition.

If you're going to swap out of the Eibachs, I'd probably go with ST X coils instead and be done with it.

If you would rather stick with springs and stock dampers, i'd be more inclined to try the Eibach 330i rwd springs 1-22, however you can start down another "rabbit hole" with guessing and chasing. Which is why I recommended coilovers.
.

[jmanB45]

Originally Posted by YODI

I think I am going to do just that, H&R are usually quite low but I love the feel of Eibachs as its almost OEM

If you're looking to change just the rear, check out this thread by FaRKle! for a DIY adjustable setup:

https://f30.bimmerpost.com/forums/sh....php?t=1652333

Also, pondering why the rear was high even before the spring swap, could the shocks be a factor? Are they OE?

[YODI]

Yes OEM adaptive suspension, I just assumed it was a bit high because it's X-Drive

Thanks for the link will take a look now.

[jmanB45]

KW/ST also has a HAS kit. Maybe just buy the rear parts?

Lowering F/R: 15-35mm/10-30mm

https://www.kwsuspensions.co.uk/shop...sions/273200AE

[YODI]

Originally Posted by jmanB45

KW/ST also has a HAS kit. Maybe just buy the rear parts?

Lowering F/R: 15-35mm/10-30mm

https://www.kwsuspensions.co.uk/shop...sions/273200AE

£706 for a set of adjustable springs seems crazy money, the link you posted above from Farkle seems like a much better option

[jmanB45]

Originally Posted by YODI

£706 for a set of adjustable springs seems crazy money, the link you posted above from Farkle seems like a much better option

You might be able to buy just the rear springs and adjusters from KW. Takes away the guesswork on spring rates and lengths compared to the DIY option.

[inthefade]

Originally Posted by johnung

Yes, I have a 2015 335ix with KoniSA's and Eibach -06 kit right now. It's looking like I'm going to swap in the Eibach -05 springs when the weather warms up. The rear springs on the two kits are identical.

The front springs have exactly the same spring rates so the ride should essentially be the same. The -06 lower the front by 20mm under stock. Accordingly Eibach tech support the -05 front springs should drop my front by another 15mm.

At the same time I'll swap in the F80 bump stops and change out the rubber spring perches that have 8 years on them.

Hey johnung,

Firstly thank you for all your contributions here for the eibach springs.

I got a 18 340i xdrive with EDC at 57k miles no leaking struts thankfully.
I know you went from the -06 to the -05, do you still recommend this?
Was initially considering the -06 so it would be easier on the struts especially at my mileage, but the -05 looks much better and considering they have the same spring rates I thought I might be able to get away with using the -05’s.

Any advice?

[johnung]

Originally Posted by inthefade

Hey johnung,

Firstly thank you for all your contributions here for the eibach springs.

I got a 18 340i xdrive with EDC at 57k miles no leaking struts thankfully.
I know you went from the -06 to the -05, do you still recommend this?
Was initially considering the -06 so it would be easier on the struts especially at my mileage, but the -05 looks much better and considering they have the same spring rates I thought I might be able to get away with using the -05’s.

Any advice?

You are welcome! Glad you found my stuff helpful. Yes, I’m very happy having gone from the drop of the Eibach -06 kit (E10-20-031-06-22) Front -0.8”/20mm, Rear -0.6”/15mm to the Eibach -05 kit (E10-20-031-05-22) Front -1.4”/35mm, Rear 0.6”/15mm. As you mentioned the spring rates are identical so they ride the same.

This could be my imagination but sometimes when I was driving the -06 springs the front end of my car occasionally felt a little high. But I haven’t felt that since installing the -05 springs. It’s only a front drop difference of another -0.6”/15mm, but who knows.

With either spring kit, upgrade to the denser F80 bump stops. They should be shorter but I haven’t gotten confirmed bump stop heights for the bmw part numbers used with Adaptives.

IMO the Adaptive dampers hold up much better than standard dampers. They seem to handle spring drop well. Adaptives seem to hold up in daily driving even up to 95k miles. And if one Adaptive starts leaking fluid, just that front or rear pair need be replaced. It used to be expensive to replace Adaptives because the Bilstein B4-Damptronic were the only replacement option. And often they were out of stock for months at a time because they are a low manufacturing priority for Bilstein.

But high quality reasonably priced MonroeEDC dampers are available now. Made in Europe. Only limited part numbers are available at a few US retailers. But it’s very easy and still very cost effective to have them shipped from Europe.

For years I’ve been using a German retailer originally recommended to me by Farkle. Great for things like Eibach -05 springs and MonroeEDC dampers. Only takes 1-2 weeks to receive shipment from Germany. Just email Andreas DOT Schade AT gmx DOT de with VIN, part number and shipping address.

FOR STANDARD NON-ADAPTIVE STRUTS & SHOCKS
The experience has caused me to change some of my recommendations with these Eibach spring kits with standard non-Adaptive dampers and also with bump stops.

KONI SA OR SPORT DAMPERS?
For -06 Eibach springs, either the Koni Special Actives or Koni Sport Yellows (adjustable for comfort/rebound) are fine. But for the -05 Eibach springs, I’d only recommend the Koni Sports, not the Koni SA’s. For either setup I’d recommend the F80 bump stops.

KONI ADVISES
This strategy follows along with Koni recommendations. I’ve had a number of conversations with Koni tech support about it. It’s not due to damper travel length as the Koni SA & Sport have identical travel lengths. The Koni SA is unique in the FSD technology that Koni developed with McLaren. It uses two valves that are tuned to different road frequencies to be able to passively adapt to provide comfort on rough roads or sporty damping on fun curves. This all works great at stock spring height which Koni (and European suspension companies in general define as less than -1”/25mm drop. (Americans take “stock height” to literally mean stock height with no drop). Just a language difference. Bilstein for example interprets it the same way.

When the Koni SA’s are dropped by >1”/25mm the odds are that they hit bump stops more and even bottom out causing different frequencies that essentially confuse the frequency tuned valves. The Koni Sports are a better solution for greater drops. They have a different internal design that’s made to handle spring drops.

BUMP STOPS
We often read that when using drop springs, to install shorter bump stops or trim existing bump stops. Dropping the chassis height reduces the distance before the bump stop is contacted. So a shorter bump stop increases that distance back towards stock. It can screw up the ride if minor road bumps cause hitting the bump stops.

FUNCTION OF A BUMP STOP
The function of a bump stop is to act as an intermediary so if the roadway overwhelms the spring, the damper won’t just abruptly slam/bottom out. This system relies on the foam bump stop having a higher spring rate than the road springs. So if the road springs are abruptly overwhelmed, there is something stronger in place to stand up to that force.

BUMP STOP SPRING RATES
Look at the shape of a bump stop. The bottom which takes the initial impact force is designed to be weaker with a smaller diameter. It even has bottom cutouts so foam prongs take that initial force for a smooth transition. The diameter of the bump stop increases as it goes from bottom to top. So a bump stop acts like a progressive spring. It has an initial spring rate that increases as it compresses from more force.

Bump stops are part of a well designed damper system within the overall suspension system design. But changing one component without understanding its function, can have undesirable consequences.

STOCK BUMP STOPS TOO WEAK?
The stock bump stop height and bump stop spring rates are designed for the stock damper travel and the stock road spring rate. Install a lowering spring that reduces damper travel and increases road spring rate can potentially cause a big problem if the stock bump stops are reused. The chassis will come down on the bump stop sooner as the road force overwhelms the road spring. And if the spring rate of the new road spring is greater than the spring rates of the stock bump stop- then it may abruptly bottom out. The stock bump stop won’t be able to offer resistance against an overwhelming force. It may be like having no bump stops in the way at all.

UPGRADE TO F80 BUMP STOPS
A common solution is to upgrade the stock bump stops to F80 bump stops that are both shorter, and made of denser foam for higher bump stop spring rates. See attached photos for part numbers. Most just want to be told to upgrade to the F80 bump stops so that’s what they do. But unless they lookup their stock bump stop part numbers on realoem, and measure their heights, they will have no idea how much shorter the F80 bump stops are on their car, if at all.

DINAN BUMP STOPS
Some people think that paying Dinan to send them bump stops is the solution. They believe the Dinan slick marketing that they were carefully engineered, right? Wrong! Dinan has been pulling what IMO is a bump stop scam for many years. Dinan is only marking up BMW bump stops from other BMW cars and marketing them as carefully chosen for your car. But if you examine a Dinan bump stop kit it is listed for a variety of cars with different chassis heights and different stock bump stops. Each Dinan bump stop kit is for a range of cars, not carefully chosen for yours specifically. The lengths could be way off from what’s needed for your chosen springs & drops.

Years ago Dinan would give me no specs on the bump stops in their kit for my car. I said okay what if I buy a Dinan bump stop kit, and F80 bump stops and compare them all to my stock bump stops and my new spring drops to choose which works best? If I don’t use the Dinan kit, can I return it? Dinan said “NO!” They heavily guard which BMW part numbers are in their Dinan kits or there would be no reason to buy them from Dinan.

Hope this helps someone!

[inthefade]

Originally Posted by johnung

You are welcome! Glad you found my stuff helpful. Yes, I’m very happy having gone from the drop of the Eibach -06 kit (E10-20-031-06-22) Front -0.8”/20mm, Rear -0.6”/15mm to the Eibach -05 kit (E10-20-031-05-22) Front -1.4”/35mm, Rear 0.6”/15mm. As you mentioned the spring rates are identical so they ride the same.

This could be my imagination but sometimes when I was driving the -06 springs the front end of my car occasionally felt a little high. But I haven’t felt that since installing the -05 springs. It’s only a front drop difference of another -0.6”/15mm, but who knows.

With either spring kit, upgrade to the denser F80 bump stops. They should be shorter but I haven’t gotten confirmed bump stop heights for the bmw part numbers used with Adaptives.

IMO the Adaptive dampers hold up much better than standard dampers. They seem to handle spring drop well. Adaptives seem to hold up in daily driving even up to 95k miles. And if one Adaptive starts leaking fluid, just that front or rear pair need be replaced. It used to be expensive to replace Adaptives because the Bilstein B4-Damptronic were the only replacement option. And often they were out of stock for months at a time because they are a low manufacturing priority for Bilstein.

But high quality reasonably priced MonroeEDC dampers are available now. Made in Europe. Only limited part numbers are available at a few US retailers. But it’s very easy and still very cost effective to have them shipped from Europe.

For years I’ve been using a German retailer originally recommended to me by Farkle. Great for things like Eibach -05 springs and MonroeEDC dampers. Only takes 1-2 weeks to receive shipment from Germany. Just email Andreas DOT Schade AT gmx DOT de with VIN, part number and shipping address.

FOR STANDARD NON-ADAPTIVE STRUTS & SHOCKS
The experience has caused me to change some of my recommendations with these Eibach spring kits with standard non-Adaptive dampers and also with bump stops.

KONI SA OR SPORT DAMPERS?
For -06 Eibach springs, either the Koni Special Actives or Koni Sport Yellows (adjustable for comfort/rebound) are fine. But for the -05 Eibach springs, I’d only recommend the Koni Sports, not the Koni SA’s. For either setup I’d recommend the F80 bump stops.

KONI ADVISES
This strategy follows along with Koni recommendations. I’ve had a number of conversations with Koni tech support about it. It’s not due to damper travel length as the Koni SA & Sport have identical travel lengths. The Koni SA is unique in the FSD technology that Koni developed with McLaren. It uses two valves that are tuned to different road frequencies to be able to passively adapt to provide comfort on rough roads or sporty damping on fun curves. This all works great at stock spring height which Koni (and European suspension companies in general define as less than -1”/25mm drop. (Americans take “stock height” to literally mean stock height with no drop). Just a language difference. Bilstein for example interprets it the same way.

When the Koni SA’s are dropped by >1”/25mm the odds are that they hit bump stops more and even bottom out causing different frequencies that essentially confuse the frequency tuned valves. The Koni Sports are a better solution for greater drops. They have a different internal design that’s made to handle spring drops.

BUMP STOPS
We often read that when using drop springs, to install shorter bump stops or trim existing bump stops. Dropping the chassis height reduces the distance before the bump stop is contacted. So a shorter bump stop increases that distance back towards stock. It can screw up the ride if minor road bumps cause hitting the bump stops.

FUNCTION OF A BUMP STOP
The function of a bump stop is to act as an intermediary so if the roadway overwhelms the spring, the damper won’t just abruptly slam/bottom out. This system relies on the foam bump stop having a higher spring rate than the road springs. So if the road springs are abruptly overwhelmed, there is something stronger in place to stand up to that force.

BUMP STOP SPRING RATES
Look at the shape of a bump stop. The bottom which takes the initial impact force is designed to be weaker with a smaller diameter. It even has bottom cutouts so foam prongs take that initial force for a smooth transition. The diameter of the bump stop increases as it goes from bottom to top. So a bump stop acts like a progressive spring. It has an initial spring rate that increases as it compresses from more force.

Bump stops are part of a well designed damper system within the overall suspension system design. But changing one component without understanding its function, can have undesirable consequences.

STOCK BUMP STOPS TOO WEAK?
The stock bump stop height and bump stop spring rates are designed for the stock damper travel and the stock road spring rate. Install a lowering spring that reduces damper travel and increases road spring rate can potentially cause a big problem if the stock bump stops are reused. The chassis will come down on the bump stop sooner as the road force overwhelms the road spring. And if the spring rate of the new road spring is greater than the spring rates of the stock bump stop- then it may abruptly bottom out. The stock bump stop won’t be able to offer resistance against an overwhelming force. It may be like having no bump stops in the way at all.

UPGRADE TO F80 BUMP STOPS
A common solution is to upgrade the stock bump stops to F80 bump stops that are both shorter, and made of denser foam for higher bump stop spring rates. See attached photos for part numbers. Most just want to be told to upgrade to the F80 bump stops so that’s what they do. But unless they lookup their stock bump stop part numbers on realoem, and measure their heights, they will have no idea how much shorter the F80 bump stops are on their car, if at all.

DINAN BUMP STOPS
Some people think that paying Dinan to send them bump stops is the solution. They believe the Dinan slick marketing that they were carefully engineered, right? Wrong! Dinan has been pulling what IMO is a bump stop scam for many years. Dinan is only marking up BMW bump stops from other BMW cars and marketing them as carefully chosen for your car. But if you examine a Dinan bump stop kit it is listed for a variety of cars with different chassis heights and different stock bump stops. Each Dinan bump stop kit is for a range of cars, not carefully chosen for yours specifically. The lengths could be way off from what’s needed for your chosen springs & drops.

Years ago Dinan would give me no specs on the bump stops in their kit for my car. I said okay what if I buy a Dinan bump stop kit, and F80 bump stops and compare them all to my stock bump stops and my new spring drops to choose which works best? If I don’t use the Dinan kit, can I return it? Dinan said “NO!” They heavily guard which BMW part numbers are in their Dinan kits or there would be no reason to buy them from Dinan.

Hope this helps someone!

Immensely helpful, thank you!

Glad to hear the switch has worked out for you

[Morv]

Hello guys

So I've got F36 430i LCI X-Drive (non Adaptive Suspension) for over two months now and I decided to go lower just like my E46. But there is a problem and its called X-Drive so I cant go mad.

I see there is a few wise mens here and they know what is what in lowering spring world. I was searching for few days and still dont know which springs should I choose.

The best scenario would be -30mm lowering but I dont know If its possible with Eibach or H&R.

On Eibach site they recommend E10-20-031-04-22 -25mm -20mm. Can I get any lower with -03-22 or 05-22?

Thanks for answers. It's unbelievable for the m-sport version to have a 70 millimeter gap between the wheel and the fender...

[jmanB45]

Originally Posted by Morv

On Eibach site they recommend E10-20-031-04-22 -25mm -20mm. Can I get any lower with -03-22 or 05-22?

For a 30mm front drop, you want the 03-22.

05-22 is for the 6 cylinder cars.

https://f30.bimmerpost.com/forums/sh...9&postcount=39

Edit: If you're planning to keep the stock dampers, the 04-22 kit is the better option. If you're picky about having the perfect the ride height, do it once and do it right with coilovers; ST or KW are solid choices.

[Morv]

No I'm not picky about lowering car this time. I've got E46 and it looks great but cant enter many places calmly because how low it is.

I just want something like -30front and -20/-30 rear on F36 and yeah I know this topic from 1st to last site. I saw many few photos on google and FB groups but well I can't tell which springs should I buy.

From some people I saw that H&R springs are great in lowering but in other photos it looks almost like stock... and I heard that H&R are more stiff than Eibach ones.

Dampers will stay stock for now but I will change them in future If one of them fails.

It looks like SUV right now... And yeah I will change these wheels for 19inch in next season.