[Knifeedge2k1]

Originally Posted by Joe-BMW33

I agree and I also can respect that. As a newbie, I trust this shop and all the modifications they have done. One of my biggest apprehensions is the invasive nature of the install. Ripping out the trunk and the back seat. The owner of the shop was honest with me, he says nothing ever goes back the same. He said it would be unnoticeable to me, but this has me a little anxious. The other thing is for all the invasiveness and big expense, what if I am not happy with the ride? I'd say my main hunt in lowering it a tad so the wheels and spacers look better and second, improving the body roll. I live in an area where they NEVER repave the roads, they just patch, patch, patch. So anything off the highway is a bumpy ride. Lastly, if I move forward, I am hoping a 0.75" won't make the front end scrape over speed bumps, the end of my driveway is a like a speed bump and then downhill. I already have to come in and out at an angle.

My history is like Murphy's law, if something could go wrong it will and the definition of wrong in this case would be buyers remorse.

I have been procrastinating about this for almost a year!! It doesn't help that I got an email this morning saying the Dinan springs are back in stock! Coilovers seem like good solution, but my limited research for the quality one's are $2,500+. Add that to the $1,400 and I am in this for $4,000 grand. A lot to think about.

It's good you're realistic and cognizant of your environment

As always do your own research and take everyone's advice (especially randoms like me on the internet) with a pinch of salt

If you want roll control, you can get the M5 (or any number of G30 OEM) sway bars for pretty cheap brand new but they're not adjustable (most aftermarket sways only have 2 holes anyways for the G30 platform)

I actually went through and collected every single part number so I've got the library of p/n for front and rear sways that fit the G30 platform.

For me the body roll is not that bad and like you roads in my area (particularly the fun mountain ones) have patches on patches on patches. The msport suspension rides plenty firm enough for me so all I did to liven up the car a bit is stiffen the rear swaybar from 18mm stock msport to 24.5mm from the 550i which dials out enough understeer that I'm genuinely concerned about the rear stepping out anytime the sky gets so much as a bit misty (I honestly probably over did it).

I also live in a place (Hong Kong) that has plenty of elevation changes and stuff built into the sides of mountains so wheel travel and articulation were paramount so even a 0.5 inch lowering isn't something I would want to have but that's just me.

The main benefit of the coils is 3 fold in no particular order

1) lowering and rise height control /adjustable (why 95% of people buy them)
2) corner weighting (you can't do this on normal lowering springs)
3)damping adjustability (rebound /compression, high vs low speed damping rates etc)

No real need to cover 1)

2) if you don't track or autocross you really don't even need to know what this is

3) most people have weird/wrong idea of what ride quality/compliance actually is and give objectively wrong feedback or impressions of a given change. While everyone has a different preference for what they did comfortable, butt dyno opinions mean shit when talking about objective things.

If labor was free (you did work yourself) and you don't track/autox the car or even drive it quickly in dynamic conditions (i.e not a straight line) then lowering springs with a mild lower are perfectly acceptable solution for those looking for the look of a lowered car. If you are actually pushing the car's limit (you regularly hear your tires howl) then springs are simply not a good solution.

[Joe-BMW33]

Originally Posted by Knifeedge2k1

It's good you're realistic and cognizant of your environment

As always do your own research and take everyone's advice (especially randoms like me on the internet) with a pinch of salt

If you want roll control, you can get the M5 (or any number of G30 OEM) sway bars for pretty cheap brand new but they're not adjustable (most aftermarket sways only have 2 holes anyways for the G30 platform)

I actually went through and collected every single part number so I've got the library of p/n for front and rear sways that fit the G30 platform.

For me the body roll is not that bad and like you roads in my area (particularly the fun mountain ones) have patches on patches on patches. The msport suspension rides plenty firm enough for me so all I did to liven up the car a bit is stiffen the rear swaybar from 18mm stock msport to 24.5mm from the 550i which dials out enough understeer that I'm genuinely concerned about the rear stepping out anytime the sky gets so much as a bit misty (I honestly probably over did it).

I also live in a place (Hong Kong) that has plenty of elevation changes and stuff built into the sides of mountains so wheel travel and articulation were paramount so even a 0.5 inch lowering isn't something I would want to have but that's just me.

The main benefit of the coils is 3 fold in no particular order

1) lowering and rise height control /adjustable (why 95% of people buy them)
2) corner weighting (you can't do this on normal lowering springs)
3)damping adjustability (rebound /compression, high vs low speed damping rates etc)

No real need to cover 1)

2) if you don't track or autocross you really don't even need to know what this is

3) most people have weird/wrong idea of what ride quality/compliance actually is and give objectively wrong feedback or impressions of a given change. While everyone has a different preference for what they did comfortable, butt dyno opinions mean shit when talking about objective things.

If labor was free (you did work yourself) and you don't track/autox the car or even drive it quickly in dynamic conditions (i.e not a straight line) then lowering springs with a mild lower are perfectly acceptable solution for those looking for the look of a lowered car. If you are actually pushing the car's limit (you regularly hear your tires howl) then springs are simply not a good solution.

This is excellent and you ARE NOT some guy on the internet. This is really helping me with my thought process. I do not drive the car hard and I do not track it. I have never even used launch control. My priorities are 1a - aesthetics and 1b improving the body roll when simple entering and exiting an on or off ramp. I am a little spoiled because my E39 hugs like glue, but it is also a smaller car and lower to the ground.

It sounds like the Dinan springs may best fit my profile. I wish I could drive one with it first.

[Knifeedge2k1]

If your roads are truly shit, you simply shouldn't lower the car ...

No manufacturer can defeat the laws of physics, not KW, Nitron, BMW M, etc.

None of them can get around the fact that if you have less suspension travel you're gonna need a higher spring rate ... and a higher spring rate WILL transfer more energy/shock into the cabin

If you already hate the way it rides over shit roads, there's simply no way any type of stiffer suspension is going to feel better unless what you actually dislike is the way the car is damped

Originally Posted by Joe-BMW33

I agree and I also can respect that. As a newbie, I trust this shop and all the modifications they have done. One of my biggest apprehensions is the invasive nature of the install. Ripping out the trunk and the back seat. The owner of the shop was honest with me, he says nothing ever goes back the same. He said it would be unnoticeable to me, but this has me a little anxious. The other thing is for all the invasiveness and big expense, what if I am not happy with the ride? I'd say my main hunt in lowering it a tad so the wheels and spacers look better and second, improving the body roll. I live in an area where they NEVER repave the roads, they just patch, patch, patch. So anything off the highway is a bumpy ride. Lastly, if I move forward, I am hoping a 0.75" won't make the front end scrape over speed bumps, the end of my driveway is a like a speed bump and then downhill. I already have to come in and out at an angle.

My history is like Murphy's law, if something could go wrong it will and the definition of wrong in this case would be buyers remorse.

I have been procrastinating about this for almost a year!! It doesn't help that I got an email this morning saying the Dinan springs are back in stock! Coilovers seem like good solution, but my limited research for the quality one's are $2,500+. Add that to the $1,400 and I am in this for $4,000 grand. A lot to think about.

[Knifeedge2k1]

Originally Posted by Joe-BMW33

This is excellent and you ARE NOT some guy on the internet. This is really helping me with my thought process. I do not drive the car hard and I do not track it. I have never even used launch control. My priorities are 1a - aesthetics and 1b improving the body roll when simple entering and exiting an on or off ramp. I am a little spoiled because my E39 hugs like glue, but it is also a smaller car and lower to the ground.

It sounds like the Dinan springs may best fit my profile. I wish I could drive one with it first.

If you're going to get springs, atleast get the MSS springs (they have adjustability)

Sounds like anti-roll bars from the M5 can help your body roll issue without really impacting day to day bump compliance, if you don't mind can u shoot me over your VIN ?

[Knifeedge2k1]

Just think about what you're getting versus what you're giving up

Looks .. i'm not gonna argue with you whether this is a positive or negative ... but it is a benefit only when you 1) show up to car meets and 2) when you're not actually in the car and you can see it from the outside .... when you're driving you're not receiving any of the benefit of this (especially when you have shit roads)

...


what you lose is wheel travel and bump compliance (if you live on a race track, neither of those things matter to you much, based on where you live, this is a constant in the environment)

lowering doesn't improve roll resistance (much), it's a common misconception.

Yeah lower center of gravity reduces load transfer in corners but for a 1 inch drop in CG across a 63 inch track width at a CoG of something like 20 inches would be a difference in load transfer of like <2% at 1g cornering ... so no real difference in every day life (plenty of difference in motorsport, but real life ? fk no

Stiffer sways will reduce FAR more body roll than the act of simply lowering (slightly unfair statement as lowering in real life always come with stiffer springs which itself reduces roll a bit but i'm trying to paint a picture here)

[Joe-BMW33]

Originally Posted by Knifeedge2k1

Just think about what you're getting versus what you're giving up

Looks .. i'm not gonna argue with you whether this is a positive or negative ... but it is a benefit only when you 1) show up to car meets and 2) when you're not actually in the car and you can see it from the outside .... when you're driving you're not receiving any of the benefit of this (especially when you have shit roads)

...


what you lose is wheel travel and bump compliance (if you live on a race track, neither of those things matter to you much, based on where you live, this is a constant in the environment)

lowering doesn't improve roll resistance (much), it's a common misconception.

Yeah lower center of gravity reduces load transfer in corners but for a 1 inch drop in CG across a 63 inch track width at a CoG of something like 20 inches would be a difference in load transfer of like <2% at 1g cornering ... so no real difference in every day life (plenty of difference in motorsport, but real life ? fk no

Stiffer sways will reduce FAR more body roll than the act of simply lowering (slightly unfair statement as lowering in real life always come with stiffer springs which itself reduces roll a bit but i'm trying to paint a picture here)

You have given me a lot to think about and a voice of reason. I do not hate the way the car rides now. I am actually pleasantly surprised how well it rides in comfort mode and the way it handles he bumps. Much smoother than people led me to believe before getting the car. Of course I have summer softies on it for rubber. I do not drive the car in winter and until all the potholes are filled, so that comes into play. I manage the exposure to the poor road conditions. I am very careful as well. But for example, if I were to drive the car right now in the middle of winter, there is no way I would be able to avoid all the potholes. It is like the moon right now.

I'll PM you my VIN.

[Knifeedge2k1]

If you have the electronic dampers and adjustable swaybars you really can't do much in terms of aftermarket without losing those functionalities.

Generally I'd advise against it (you paid extra for these things when you bought the car, now you're gonna scrap them ?) but it depends on what your purpose is for this vehicle. Is it the ONLY car you have and it needs to be a jack of all trades ? Do you have another "fun car" in the garage ? do you have another car that can act as the commuter/people-mover ?

I'd actually advise the MSS springs just because they have the adjustability in ride height / corner weight while retaining all the adjustability to keep the car versatile.

While coilovers or uprated sways certainly would be better for performance, only the really expensive coilovers keep the electronic damping control and NO aftermarket adjustable sway bar exists (you can go stiffer, but you lose adjustment)

In my view if you wanted the hardcore 5er ... you should have bought the M5, getting the M550 is in and of itself a signal that performance isn't everything. What you give up for the extra performance in the M5 (compared to the M550) is a more compromised every day experience, if you're gonna take all of that every day goodness out ... just trade it for an M5.

[Joe-BMW33]

Originally Posted by Knifeedge2k1

If you have the electronic dampers and adjustable swaybars you really can't do much in terms of aftermarket without losing those functionalities.

Generally I'd advise against it (you paid extra for these things when you bought the car, now you're gonna scrap them ?) but it depends on what your purpose is for this vehicle. Is it the ONLY car you have and it needs to be a jack of all trades ? Do you have another "fun car" in the garage ? do you have another car that can act as the commuter/people-mover ?

I'd actually advise the MSS springs just because they have the adjustability in ride height / corner weight while retaining all the adjustability to keep the car versatile.

While coilovers or uprated sways certainly would be better for performance, only the really expensive coilovers keep the electronic damping control and NO aftermarket adjustable sway bar exists (you can go stiffer, but you lose adjustment)

In my view if you wanted the hardcore 5er ... you should have bought the M5, getting the M550 is in and of itself a signal that performance isn't everything. What you give up for the extra performance in the M5 (compared to the M550) is a more compromised every day experience, if you're gonna take all of that every day goodness out ... just trade it for an M5.

I have a few fun cars and should be adding a Porsche to the stable in a few months. That will certainly be my ultimate handling car.

But yes, the M550 is more about the 0.75" drop for aesthetics.

[540iSUP]

Joe, I've had Lowering Springs, Cheap Coil overs, Expensive Coil overs, and Air Bags on various vehicles that I have owned and I've installed all the parts myself. @knifeedge2k1 pretty much summed everything up nicely.

It looks like you want to reduce body roll and lower the car a little bit. If this is all you want and you don't care to corner balance: Eibach and H&R makes springs. (To truly reduce body roll, stiffer Anti-sway bars are needed) If you want adjustability, then go with MSS. If you want to be able to adjust ride height (corner balance) and dampening, go with coilovers. If you just want to lower your car and drive at a normal ride height, then Air is the way to go.

No matter what solution you go with, you will be removing the shocks and either replacing the springs, or the entire shock and spring assembly. For the front, its 3 bolts on top and maybe 2 or more on bottom. The rear is basically the same, but there might be 1-3 bolts on top. The rear deck lid and rear seat side bolsters need to be removed to access the top bolts in the rear. These pieces pop right off and snap back in place without issue. An alignment is always recommended when working on suspension, one caveat is that when installing springs, you should wait about a week or more for them to settle before getting an alignment.

Also keep in mind that if you have adaptive suspension, you're better off keeping the OEM dampers and going with MSS, Eibach, or H&R.

[Joe-BMW33]

Originally Posted by 540iSUP

Joe, I've had Lowering Springs, Cheap Coil overs, Expensive Coil overs, and Air Bags on various vehicles that I have owned and I've installed all the parts myself. @knifeedge2k1 pretty much summed everything up nicely.

It looks like you want to reduce body roll and lower the car a little bit. If this is all you want and you don't care to corner balance: Eibach and H&R makes springs. (To truly reduce body roll, stiffer Anti-sway bars are needed) If you want adjustability, then go with MSS. If you want to be able to adjust ride height (corner balance) and dampening, go with coilovers. If you just want to lower your car and drive at a normal ride height, then Air is the way to go.

No matter what solution you go with, you will be removing the shocks and either replacing the springs, or the entire shock and spring assembly. For the front, its 3 bolts on top and maybe 2 or more on bottom. The rear is basically the same, but there might be 1-3 bolts on top. The rear deck lid and rear seat side bolsters need to be removed to access the top bolts in the rear. These pieces pop right off and snap back in place without issue. An alignment is always recommended when working on suspension, one caveat is that when installing springs, you should wait about a week or more for them to settle before getting an alignment.

Also keep in mind that if you have adaptive suspension, you're better off keeping the OEM dampers and going with MSS, Eibach, or H&R.

Thanks for this, you know I value your input. I wish I was a DIY'er still. As of right now, I am thinking of passing on the springs. You are spot on, my hunt is a small drop for aesthetics and a bonus would be improved body roll.

[Superjackson]

You know, tires can help with body roll a lot as well as filling the wheel well better. Having wider tires in the front, like 275s, will improve road feel and stability in corners immensely. Also, $1400 in labor is insane. Every shop quoted me under $600 CAD with alignment included when I needed my coilovers installed..