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Discussion Starter #1
I have read a lot here about lowering the front end, with lowering springs. Some think it will ruin the handling, ruin the comfort, that it will look slammed, look raked, etc.
I am a former suspension design engineer from a well known suspension manufacturer, the worlds leading actually (not mentioning any names here). I did some investigations to see what kind of suspension system that's fitted on the M5, since I have one and I wasn't too happy about the gap between the front wheel and fender and the under-steer in some situations, on an otherwise near perfect car.
I scanned the net for after market spring kits and found the German designed Lowtec springs, bought a set of front springs (25 mm lowering, about 1 inch), installed them and did a 4 wheel chassis adjustment. The actual difference in ride height was 23 mm and it will probably be around 25 mm, when the springs are run in.
The springs are not much shorter than stock, but have a more progressive spring rate, giving more sag. When the car is lifted up, the spring still have pre-load left and is not sitting loose.
I can say that so far I am happy with the results. The wheel-to-fender-gap is equal all around the car now, it does NOT look neither raked nor slammed. The handling is not ruined nor the comfort. It handles with a tad bit less under-steer, but hardly detectable. The HID lights adjusted them self. Thanks to the EDC-system the results from just installing lowering springs are far better than on a passive damping system. Just changing springs is a shortcut, that sometimes won't give the results you want. Coil overs can be an option for people that are not happy with the chassis stock performance, but you will loose the ability to use the EDC-control and I am sure that the engineers at BMW did their homework setting up this car.
Some cautions:
I would not recommend lowering more than this, with stock shocks, due to an increased pressure in the shocks and loss of wheel travel.
Protect the fenders before removing the suspension.
And don't forget to make a 4-wheel chassis adjustment after installing the springs! Don't skip this, it may become a costly mistake.



I have posted some before/after pictures
 

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Nice write-up. Did you make any adjustments to the rear? Why did you choose this brand over dinan, eibach or H&R? Any chance your affiliated with them?
 

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Hmm never heard of this company before. Looks good!!
 

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I would have replaced all 4 springs honestly.
 

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Discussion Starter #5
Thanks! I got my hands on some specs for these springs, compared them with other options and given my experience in suspension technology, I decided that it was worth a try. I have both warranty and satisfied customer guarantee on this product, so I feel safe. The pricing is quite moderate also. I know that this kind of springs cost about 25-40 USD/pcs to make. No, I am not affiliated with any of them.
 

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Discussion Starter #6
I would have replaced all 4 springs honestly.
I wanted to lower the font a bit, because the front ride height was actually taller than the rear, causing a bit more under steer than I wanted. Also the tall front end, was the only thing i didn't love about the looks on my M5.
If you want a more level ride height, I'd not recommend swapping all springs, since they will lower the rear as well, and you are pretty much back to where you started. No adjustments needed to be done to the rear suspension. Most lowering spring kits, for both front and rear, will lower rear 20-25 mm and front approx 40 mm. That's a bit too much for the stock shocks, even for EDC shocks. It will affect ride comfort and the factory settings in the stock shocks.
And there is no reason to change the stock springs if you are happy with the ride height/looks! They are good quality springs, tailor made for this specific model and a good compromise between comfort and sport. No spring kits will give any significant improvement in handling.
 

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Do you know who manufactures OEM springs for BMW?
 

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Discussion Starter #8
Do you know who manufactures OEM springs for BMW?
Yes, if I'm not misinformed, it should be Sachs suspension. Also the Shocks and EDC-system.
 

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The car is designed to be balanced and lowering the front only would potentially mess with that balance. My car is about an inch lower then stock but that is all the way around. Ive not heard of anyone just lowering the front. Hope you like how it turned out though.
 

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Discussion Starter #11
The car is designed to be balanced and lowering the front only would potentially mess with that balance. My car is about an inch lower then stock but that is all the way around. Ive not heard of anyone just lowering the front. Hope you like how it turned out though.
Yes, I agree and I know all about this, hence I'm a former suspension engineer and I have a masters degree in mechanical engineering and vehicle dynamics. And you should know what you are doing, when playing around with the chassis set-up. But this is a car for public road use and daily driving, with a sporty set-up. It's supposed to be as safe as possible and that means it has got some under steer. I like to have it neutral, or as close as possible to neutral. But my main issue was the looks, the factory set-up is quite OK when it comes to handling. Some basic calculations and work in my CAD-system, shows that lowering 23-25 mm in the front, will give a near neutral balance. The more progressive spring rate means it won't dive more when braking. So the balance when braking is almost like stock, which means safety first.
If you look at most lowering kits for the M5, they will lower the front end more than the rear. Most kits will give 15-25 mm more lowering in the front. I don't want to lower more than this, since I need the ground clearance.
Yes, so far I have no regrets about lowering the front end.
 

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Discussion Starter #12
Where can I get a set of these? Btw who makes Dinan's springs?
Hmm... I can't find any dealer in the US, only Europe. I bought them here: Schmiedmann Sverige - Sök - Nya delar - sida 1
Don't know about over-seas sales.

No, I don't know who makes Dinan springs. There are a handfull of quality spring manufacturers in Europe and a few in Asia. I'm pretty sure that the Dinan springs are OK too.
 

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Discussion Starter #14

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Hmm... I can't find any dealer in the US, only Europe. I bought them here: Schmiedmann Sverige - Sök - Nya delar - sida 1
Don't know about over-seas sales.

No, I don't know who makes Dinan springs. There are a handfull of quality spring manufacturers in Europe and a few in Asia. I'm pretty sure that the Dinan springs are OK too.
I really have the same philosophy as you when it comes to lowering the front. I feel the rear is fine and only want to close the gap a little without affecting ride and EDC function. Thus this has definitely picqued my interest. I contacted madeone.com about exporting a set to the us so let's see roughly how much would that be. How much should I expect to pay for a front set in your experience?
 

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Discussion Starter #16
I really have the same philosophy as you when it comes to lowering the front. I feel the rear is fine and only want to close the gap a little without affecting ride and EDC function. Thus this has definitely picqued my interest. I contacted madeone.com about exporting a set to the us so let's see roughly how much would that be. How much should I expect to pay for a front set in your experience?
Approx $250-300, plus shipping, should be an OK price. (I payed $260 incl. VAT, for mine, here in Sweden)
Good luck! And don't forget to do the 4 wheel adjustment afterwards :M5thumbs:
 

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Looking to go this route as well (there are quite a few speedbumps around here...). I like all the looks of the stock car except it looks like it is in the middle launching at a drag strip when it is standing still. There are 25mm or 40mm options for lowering only the front. I want a slight rake so I may try out the 40mm.

I also want to keep the stock spring rate as I drive my 6 month old quite often. It would be perfect if I could just lower the front an inch or so without changing spring rates and this looks like the best option.

Kenneth, have you had any issues with them? No regrets after a few years?

Total cost for the front only is $175 + $30 s/h from Germany. Not bad to save a few $$$ either. Labor will only be 1/2 of the cost as swapping out all 4 springs.

I assume there will be no rebound issues as the front only kits are TUV approved.

Edit: 30mm option is only for E39 M5...
 

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I think this might be my route as well. I can't imagine the weight distrubution would change at all by any significant amount seeing as how the car is only about 53/47 to start with. The only way I can see it ever being noticed is if you had the car corner balanced and I would be surprised if any M5 ever has been.

With stock height, OEM wheels and 12.5 spacers, I don't want the rear going down any more. The front though? I could camp under that thing.
 

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Discussion Starter #20
I would go for the 25 mm version. I think that 40 mm is too much for the stock shocks.
I have no regrets at all. They work perfectly and they have not settled any further than they did within a month after the installation (about 2-3 mm).
Springs that lower as much as 40 mm, will affect the ride comfort.

Order the 25 mm kit and Go for it! :)

Looking to go this route as well (there are quite a few speedbumps around here...). I like all the looks of the stock car except it looks like it is in the middle launching at a drag strip when it is standing still. There are 25mm or 40mm options for lowering only the front. I want a slight rake so I may try out the 40mm.

I also want to keep the stock spring rate as I drive my 6 month old quite often. It would be perfect if I could just lower the front an inch or so without changing spring rates and this looks like the best option.

Kenneth, have you had any issues with them? No regrets after a few years?

Total cost for the front only is $175 + $30 s/h from Germany. Not bad to save a few $$$ either. Labor will only be 1/2 of the cost as swapping out all 4 springs.

I assume there will be no rebound issues as the front only kits are TUV approved.

Edit: 30mm option is only for E39 M5...
 
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