[dr.roro]

2015 F32 435i M Sport, RWD, 8AT, Adaptive M Suspension
Daily driver, occasional autocross, maybe once/yr track in future

Debating M Performance LSD vs. KW Street Comfort coilovers. Both are about $2000 + $500 install (rough numbers).

Which is the better bang for buck? Which will make the greater difference in overall handling and feel?

[Polo08816]

Originally Posted by dr.roro

2015 F32 435i M Sport, RWD, 8AT
Daily driver, occasional autocross, maybe once/yr track in future

Debating M Performance LSD vs. KW Street Comfort coilovers. Both are about $2000 + $500 install (rough numbers).

Which is the better bang for buck? Which will make the greater difference in overall handling and feel?

I don't have the KW Street Comfort coilovers, but I do have the M Performance Suspension and M Performance LSD and have installed both myself.

I believe the M Performance LSD made the bigger difference. Replace your suspension when your original ones are worn out. I think it's a not a great use of money to replace a wear/tear item prior to the completion of its usable life.

[F30_SixSpeed]

Originally Posted by Polo08816

I don't have the KW Street Comfort coilovers, but I do have the M Performance Suspension and M Performance LSD and have installed both myself.

I believe the M Performance LSD made the bigger difference. Replace your suspension when your original ones are worn out. I think it's a not a great use of money to replace a wear/tear item prior to the completion of its usable life.

I respectively disagree. One of the biggest complaints I've had about the f30 (I have 335i m sport with EDC sport suspension) was the suspension. It was extremely floaty on highway speeds and not stiff at all. I've fitted my car with KW V2 Coilovers with the EDC module and the difference it literally night and day... one of my favorite mods I've done. Car is a lot more predictable and I can control the car significantly better...cornering is vastly improved... not to mention the ride is more comfortable then stock

I drive my car hard with occasional track days. My car put down 473wtrq and i don't have too many problems with traction or power distribution even when pushing it. I plan on eventually picking up an LSD, but for now I'm very happy with the setup... suspension will help with traction/power distribution as well. I vote coil overs.

[dr.roro]

Originally Posted by Polo08816

I don't have the KW Street Comfort coilovers, but I do have the M Performance Suspension and M Performance LSD and have installed both myself.

I believe the M Performance LSD made the bigger difference. Replace your suspension when your original ones are worn out. I think it's a not a great use of money to replace a wear/tear item prior to the completion of its usable life.

Thanks for your input.

When would you expect stock suspension to be due for replacement?
How long do you expect the M Performance LSD to last given it is a mechanical clutch-type LSD? What is your plan for rebuilding or replacing it when it reaches end of life?

Originally Posted by F30_SixSpeed

I respectively disagree. One of the biggest complaints I've had about the f30 (I have 335i m sport with EDC sport suspension) was the suspension. It was extremely floaty on highway speeds and not stiff at all. I've fitted my car with KW V2 Coilovers with the EDC module and the difference it literally night and day... one of my favorite mods I've done. Car is a lot more predictable and I can control the car significantly better...cornering is vastly improved... not to mention the ride is more comfortable then stock

I drive my car hard with occasional track days. My car put down 473wtrq and i don't have too many problems with traction or power distribution even when pushing it. I plan on eventually picking up an LSD, but for now I'm very happy with the setup... suspension will help with traction/power distribution as well. I vote coil overs.

Thanks for your input as well. I'd be interested to hear your thoughts if/when you get the LSD.

[alohasurftoad]

I do not have either choice but have m-perf. susp.

The lsd is realized mostly while pushing the car during sporty or greater driving.

The best bang for buck would have to be the suspension as it is realized all the time. From daily driving to track and even while its parked (appearance).

So you're willing to give up adaptive if you get susp? Are street comfort better than v2 for your needs?

[Polo08816]

Originally Posted by F30_SixSpeed

I respectively disagree. One of the biggest complaints I've had about the f30 (I have 335i m sport with EDC sport suspension) was the suspension. It was extremely floaty on highway speeds and not stiff at all. I've fitted my car with KW V2 Coilovers with the EDC module and the difference it literally night and day... one of my favorite mods I've done. Car is a lot more predictable and I can control the car significantly better...cornering is vastly improved... not to mention the ride is more comfortable then stock

I drive my car hard with occasional track days. My car put down 473wtrq and i don't have too many problems with traction or power distribution even when pushing it. I plan on eventually picking up an LSD, but for now I'm very happy with the setup... suspension will help with traction/power distribution as well. I vote coil overs.

While the stock 704 Sport (passive) suspension is floaty, it's still predictable. It's also a wear item so it's a waste of money to replace a wear item that's not fully worn.

Originally Posted by dr.roro

Thanks for your input.

When would you expect stock suspension to be due for replacement?
How long do you expect the M Performance LSD to last given it is a mechanical clutch-type LSD? What is your plan for rebuilding or replacing it when it reaches end of life?

I had ~70,000 miles on my passive 704 Sport Suspension before I upgraded the suspension to the M Performance Suspension. I'm uncertain about life out of the LSD. I hope it lasts another 50,000 miles at which point I would have at most one more replacement during the usable life of the car.

Originally Posted by alohasurftoad

I do not have either choice but have m-perf. susp.

The lsd is realized mostly while pushing the car during sporty or greater driving.

The best bang for buck would have to be the suspension as it is realized all the time. From daily driving to track and even while its parked (appearance).

So you're willing to give up adaptive if you get susp? Are street comfort better than v2 for your needs?

LSD makes driving at the limit much more predictable. You'll definitely notice this on the skidpad. Personally, I'd rather have more predictable handling all around especially when the traction limits are exceeded. If you upgrade the suspension to be stiff and resist roll better, that'll be fine... until you exceed the limit. Then that open differential in the rear will be more than a handful or you'll just be slow exiting corners.

I don't know how someone with > 400 ft-lbs of torque is not spinning their tires exiting corners with an open differential. I don't have any trouble spinning the inside tire with a completely stock powertrain and a square 255/40/18 Michelin Pilot Sport setup.

I do about 4-6 HPDE events per year.

[donkey]

I have neither but am doing LSD first, IMO the M sport suspension is OK but the open diff is horrible, even when driving spiritedly on the street.

[add911_11]

I have both Brids auto LSD and coilover in my F30.

I do suggest a coilover first, then LSD thereafter.

I might even venture to say get a slightly cheaper coilover (e.g. ST suspension) and do it together.

These two items on their own, or together, make a salient difference in handling so should not be missed.

[Lancelot]

I too think suspension is the most dramatic improvement you can get - and don't go cheap on it - although LSD is a solid second step.
I've got the KW DDC coilovers and Quaife LSD and like them both very much.

[Polo08816]

Originally Posted by drive

I have neither but am doing LSD first, IMO the M sport suspension is OK but the open diff is horrible, even when driving spiritedly on the street.

Originally Posted by add911_11

I have both Brids auto LSD and coilover in my F30.

I do suggest a coilover first, then LSD thereafter.

I might even venture to say get a slightly cheaper coilover (e.g. ST suspension) and do it together.

These two items on their own, or together, make a salient difference in handling so should not be missed.

Originally Posted by Lancelot

I too think suspension is the most dramatic improvement you can get - and don't go cheap on it - although LSD is a solid second step.
I've got the KW DDC coilovers and Quaife LSD and like them both very much.

Why would you do suspension first when it's a wear item? You'll have to replace it eventually. Just do it then.

It sounds like the people who advocate coilovers/suspension first instead of LSD don't do that many track events. Otherwise, they'll be losing their minds when trying to accelerate a corner and have either the DSC system robbing them of power or the rear of the car won't feel nearly as settled and controllable out of a corner on full throttle.

[BowzerF30]

OP, how many miles on are your car?

More than 60k? = Suspension then LSD

Less, invest in the LSD first

[Polo08816]

Also, if you're RWD, don't bother with anything else other than:

1. BMW M Performance Suspension Kit. The kit includes all the accessories that you need to do a proper install such as new top mounts, bolts, etc. Kit + springs: https://getbmwparts.com/partlocator/...catalogid=4462. Replacement struts + accessories: https://getbmwparts.com/parts/index....&siteid=214672 which is only $600.

2. Ohlins Road and Track - It's only ~$2300 http://www.hpashop.com/Ohlins-RT-F3x...ins-RT-F3x.htm

I don't really see the point of KW, Bilstein, any other suspension mod other than those 2.

[Lancelot]

Originally Posted by Polo08816

Why would you do suspension first when it's a wear item? You'll have to replace it eventually. Just do it then.

I've never thought of suspension as a wear item?
- Stiffer springs and dampers results in less body roll
- Lowered car results in better handling thanks to increased negative camber and lower center of gravity.

So i'm keeping the OEM suspension in my garage to replace the KW when they're worn out instead.

Originally Posted by Polo08816

It sounds like the people who advocate coilovers/suspension first instead of LSD don't do that many track events. Otherwise, they'll be losing their minds when trying to accelerate a corner and have either the DSC system robbing them of power or the rear of the car won't feel nearly as settled and controllable out of a corner on full throttle.

That may well be, as I only track my car once in a while like the OP, however I like a sharp weekend ride, and on that account both mods were very good.

[NWest]

Originally Posted by Polo08816

Also, if you're RWD, don't bother with anything else other than:

1. BMW M Performance Suspension Kit. The kit includes all the accessories that you need to do a proper install such as new top mounts, bolts, etc. Kit + springs: https://getbmwparts.com/partlocator/...catalogid=4462. Replacement struts + accessories: https://getbmwparts.com/parts/index....&siteid=214672 which is only $600.

2. Ohlins Road and Track - It's only ~$2300 http://www.hpashop.com/Ohlins-RT-F3x...ins-RT-F3x.htm

I don't really see the point of KW, Bilstein, any other suspension mod other than those 2.

Why don't you see the point in having other well engineered suspension options? Have you drove F30's with KW, Bilstein, or Ohlins?

[AFjbyers]

Originally Posted by Polo08816

I don't have the KW Street Comfort coilovers, but I do have the M Performance Suspension and M Performance LSD and have installed both myself.

I believe the M Performance LSD made the bigger difference. Replace your suspension when your original ones are worn out. I think it's a not a great use of money to replace a wear/tear item prior to the completion of its usable life.

how hard was the lsd install? Say for a decently mechanically inclined person who has installed full FBO, coilovers, camber plates, and lower control arms already in my garage?

[Polo08816]

Originally Posted by NWest

Why don't you see the point in having other well engineered suspension options? Have you drove F30's with KW, Bilstein, or Ohlins?

Because Ohlins is the gold standard for the RWD F3X chassis and there's not a significant $ savings for any of the other coilover options.

Originally Posted by AFjbyers

how hard was the lsd install? Say for a decently mechanically inclined person who has installed full FBO, coilovers, camber plates, and lower control arms already in my garage?

It requires a special tool. I've looked into doing it with standard pry bars but I'm not convinced it would work. Go over to the N55 powertrain sub-forums and read the sticky thread on the LSD.

[NWest]

OP, if this is your daily driver, from my experience (RWD and AWD), I'd definitely go with upgrading your suspension first vs. LSD for the most bang with regard to handling and road feel. In search for my own suspension upgrades, I've heard only good things about KW Street Comfort coilovers.

Originally Posted by Polo08816

Because Ohlins is the gold standard for the RWD F3X chassis and there's not a significant $ savings for any of the other coilover options.

With this logic, it makes no sense not to go with Ohlins on the RWD F3X given the time and effort required for any suspension upgrade.

[Polo08816]

Originally Posted by NWest

OP, if this is your daily driver, from my experience (RWD and AWD), I'd definitely go with upgrading your suspension first vs. LSD for the most bang with regard to handling and road feel. In search for my own suspension upgrades, I've heard only good things about KW Street Comfort coilovers.



With this logic, it makes no sense not to go with Ohlins on the RWD F3X given the time and effort required for any suspension upgrade.

Well, the problem is if this is your only daily driver, you'll have plan for significant downtime when you need to get your coilovers rebuilt. If you're just replacing worn struts, it's 1 day of downtime.

BMW M Performance Suspension Kit (which includes ~$600 work of accessories): $1500

Ohlins (~$2300) + new accessories (top hats, bolts, nuts, etc) $600 = ~$3000

[enjoythemusic]

Well, have the same setup as OP and agree if you hate the suspension go Ohlins first. Then the LSD.

[Jadar]

Originally Posted by F30_SixSpeed

I respectively disagree. One of the biggest complaints I've had about the f30 (I have 335i m sport with EDC sport suspension) was the suspension. It was extremely floaty on highway speeds and not stiff at all. I've fitted my car with KW V2 Coilovers with the EDC module and the difference it literally night and day... one of my favorite mods I've done. Car is a lot more predictable and I can control the car significantly better...cornering is vastly improved... not to mention the ride is more comfortable then stock

I drive my car hard with occasional track days. My car put down 473wtrq and i don't have too many problems with traction or power distribution even when pushing it. I plan on eventually picking up an LSD, but for now I'm very happy with the setup... suspension will help with traction/power distribution as well. I vote coil overs.

I agree while an LSD would be super fun but I wonder if I would ever see or recoup the $2500 investment as its really only noticeable on track that I never see. As the coil overs you start to feel that immediately after instal and can feel every bit of it.

[NWest]

Originally Posted by Polo08816

Well, the problem is if this is your only daily driver, you'll have plan for significant downtime when you need to get your coilovers rebuilt. If you're just replacing worn struts, it's 1 day of downtime.

BMW M Performance Suspension Kit (which includes ~$600 work of accessories): $1500

Ohlins (~$2300) + new accessories (top hats, bolts, nuts, etc) $600 = ~$3000

Well, that is if you keep your car long enough to get your aftermarket suspension rebuilt, but I would never base my decision on a suspension setup because of potential downtime or refurbishment cost at the end of its lifespan. By that time, I'm moving on to a newer car.

[Polo08816]

Originally Posted by NWest

Well, that is if you keep your car long enough to get your aftermarket suspension rebuilt, but I would never base my decision on a suspension setup because of potential downtime or refurbishment cost at the end of its lifespan. By that time, I'm moving on to a newer car.

Ohlins recommends rebuilding the suspension every 30,000 miles for optimum performance.