[Boostedphil698]

Are there any products out there to upgrade the front upper and lower control arms on Xdrive vehicles?

[johnung]

Originally Posted by Boostedphil698

Are there any products out there to upgrade the front upper and lower control arms on Xdrive vehicles?

Yes. VAC monoball control arms will get rid of the vague F-series steering feel. Steering becomes so much more precise. Note that monoballs are custom designed and manufactured so they are not commodity items. There can be a big difference in brands. VAC are the best. I’ve had them on my XDrive 335i for years. Makes a huge difference!
Note: If you can only afford one pair at a time, get the uppers first.

https://www.kiesmotorsports.com/prod...6&_ss=r?aff=22

[Boostedphil698]

Originally Posted by johnung

Yes. VAC monoball control arms will get rid of the vague F-series steering feel. Steering becomes so much more precise. Note that monoballs are custom designed and manufactured so they are not commodity items. There can be a big difference in brands. VAC are the best. I’ve had them on my XDrive 335i for years. Makes a huge difference!
Note: If you can only afford one pair at a time, get the uppers first.

https://www.kiesmotorsports.com/prod...6&_ss=r?aff=22

Interesting. I'm assuming they aren't adjustable like SPL? Have you done anything in the rear that is worth while?

[johnung]

Originally Posted by Boostedphil698

Interesting. I'm assuming they aren't adjustable like SPL? Have you done anything in the rear that is worth while?

I’m not a fan of the SPL product. I don’t see a reason to put a caster adjustment on the bushing. Never had a reason to even mess with caster. SPL just includes the bushing. It’s no picnic to press those bearings in and out. Very easy to screw up. That’s why VAC sells their monoball bushings preinstalled in brand new control arms. Their professional installation totally prevents screw ups. Plus the new arm comes with a brand new ball joint on the other end, preventing having to do the job all over again when the ball joint fails.

Over the years I have researched every rear suspension upgrade (in addition to rear shocks and springs) FaRKle! has several excellent videos on the subject where he is making rear upgrades to his track car.

The overwhelming advice that I’ve gotten from several people who I consider knowledgeable is to not do any of it to the rear on my street performance car. Pretty much anything will harsh the rear ride of a street car, and if there is an improvement it wouldn’t be noticeable at anything under track speeds and conditions.

So I view those types of rear suspension upgrades as a waste of money on a street car. Money that I’ve put into much more useful upgrades to other systems on my car..

[Boostedphil698]

Originally Posted by johnung

I’m not a fan of the SPL product. I don’t see a reason to put a caster adjustment on the bushing. Never had a reason to even mess with caster. SPL just includes the bushing. It’s no picnic to press those bearings in and out. Very easy to screw up. That’s why VAC sells their monoball bushings preinstalled in brand new control arms. Their professional installation totally prevents screw ups. Plus the new arm comes with a brand new ball joint on the other end, preventing having to do the job all over again when the ball joint fails.

Over the years I have researched every rear suspension upgrade (in addition to rear shocks and springs) FaRKle! has several excellent videos on the subject where he is making rear upgrades to his track car.

The overwhelming advice that I’ve gotten from several people who I consider knowledgeable is to not do any of it to the rear on my street performance car. Pretty much anything will harsh the rear ride of a street car, and if there is an improvement it wouldn’t be noticeable at anything under track speeds and conditions.

So I view those types of rear suspension upgrades as a waste of money on a street car. Money that I’ve put into much more useful upgrades to other systems on my car..

Gotcha. I'm trying to prep the car for 700hp N55 build. So I often worry about how factory control arms will hold up under heavy launches ans high speed.

[johnung]

Originally Posted by Boostedphil698

Gotcha. I'm trying to prep the car for 700hp N55 build. So I often worry about how factory control arms will hold up under heavy launches ans high speed.

They always over engineer parts. I haven’t heard of any problems with the arms themselves on high horsepower builds. It’s usually intricate moving parts that fail under higher punishment.

A race engineer once warned me not to be quick to replace aluminum control arms. He said that they are made of aluminum with crazy shapes because they are part of the car’s safety crumple zone system. They absorb a lot of force from getting into the cabin during an accident.

He said that when you see them replacing stock control arms with stronger straighter racing control arms, that they are part of a complete system too that includes a full roll cage, driver’s harness and helmet and fire system. He emphasized that replacing some stock parts with race parts can be a very bad, dangerous idea if race safety systems aren’t included.

[Boostedphil698]

Originally Posted by johnung

They always over engineer parts. I haven’t heard of any problems with the arms themselves on high horsepower builds. It’s usually intricate moving parts that fail under higher punishment.

A race engineer once warned me not to be quick to replace aluminum control arms. He said that they are made of aluminum with crazy shapes because they are part of the car’s safety crumple zone system. They absorb a lot of force from getting into the cabin during an accident.

He said that when you see them replacing stock control arms with stronger straighter racing control arms, that they are part of a complete system too that includes a full roll cage, driver’s harness and helmet and fire system. He emphasized that replacing some stock parts with race parts can be a very bad, dangerous idea if race safety systems aren’t included.

Interesting. Thanks for the right up!

[GuestBen]

Avoid the SPL front LCAs on XDrive! I (and many others) learned this the hard way: https://f30.bimmerpost.com/forums/sh...php?p=29290059

Even set to their shortest length, the SPLs are longer than the OEM front LCAs, enough so that they’ll stress the CV axles and eventually cause them to fail. If you want front camber adjustment on an XDrive take a different route (I eventually had a set of Millway street camber plates installed).

Not knocking SPL, fantastic company with bomber parts (I still run their front/rear monoball end links).

+1 on the VAC front LCAs/UCAs. One of the best mods you can make. Substantial improvement to driving dynamics over stock.

Good luck with your build!

[Boostedphil698]

Originally Posted by GuestBen

Avoid the SPL front LCAs on XDrive! I (and many others) learned this the hard way: https://www.bimmerpost.com/forums/sh...php?p=29254424

Even set to their shortest length, the SPLs are longer than the OEM front LCAs, enough so that they’ll stress the CV axles and eventually cause them to fail. If you want front camber adjustment on an XDrive take a different route (I eventually had a set of Millway street camber plates installed).

Not knocking SPL, fantastic company with bomber parts (I still run their front/rear monoball end links).

+1 on the VAC front LCAs/UCAs. One of the best mods you can make. Substantial improvement to driving dynamics over stock.

Good luck with your build!

Thanks man! I guess I'll take the route both you and John mentioned! Any advice for rear upgrades?

[sdbwisc]

Originally Posted by johnung

Yes. VAC monoball control arms will get rid of the vague F-series steering feel. Steering becomes so much more precise. Note that monoballs are custom designed and manufactured so they are not commodity items. There can be a big difference in brands. VAC are the best. I’ve had them on my XDrive 335i for years. Makes a huge difference!
Note: If you can only afford one pair at a time, get the uppers first.

https://www.kiesmotorsports.com/prod...6&_ss=r?aff=22

I have the upper control arms from VAC, LOVE THEM! You feel the road a bit, but not horrible. But the steering is night and day! Corning feels so much better too!

[toxik]

ive heard good things about millway's, what makes VAC better than their monoballs?

[Boostedphil698]

Originally Posted by toxik

ive heard good things about millway's, what makes VAC better than their monoballs?

I don't think Millway are compatible with Xdrive.

[toxik]

Originally Posted by Boostedphil698

I don't think Millway are compatible with Xdrive.

they have xdrive LCA/UCA

https://www.millway.se/control-arms-...lemforder.html

https://www.millway.se/front-tension...lemforder.html

[Boostedphil698]

Originally Posted by toxik

they have xdrive LCA/UCA

https://www.millway.se/control-arms-...lemforder.html

https://www.millway.se/front-tension...lemforder.html

Oh, I didn't know that. I'm not sure what makes VAC better. Maybe johnung can comment if he knows.

[toxik]

Originally Posted by Boostedphil698

Oh, I didn't know that. I'm not sure what makes VAC better. Maybe johnung can comment if he knows.

yeah i did some research not long ago, and a friend of mine bought millways for his G80 M3, I saw them in person and was very impressed with quality, plus a test drive sold me on them... mainly how little no NVH it seemed to have added. decided I will be going millway route when I replace mine in future. but that's essentially what prompted my question, I couldn't find any info on what makes VAC stand out even though that's what I see most people on F30 forums run.

i will admit, I'm a sucker for swedish made stuff also.

[Boostedphil698]

Originally Posted by toxik

yeah i did some research not long ago, and a friend of mine bought millways for his G80 M3, I saw them in person and was very impressed with quality, plus a test drive sold me on them... mainly how little no NVH it seemed to have added. decided I will be going millway route when I replace mine in future. but that's essentially what prompted my question, I couldn't find any info on what makes VAC stand out even though that's what I see most people on F30 forums run.

i will admit, I'm a sucker for swedish made stuff also.

SKF is from Sweden and they make very good bearings and bushings. No surprise the Swedes have bearing making down haha.

[johnung]

Originally Posted by toxik

ive heard good things about millway's, what makes VAC better than their monoballs?

People make the mistake of hearing the word “monoball” and assuming that it’s some generic off the shelf part. It’s not. There are a handful of brands that are designed and manufactured differently. They are apples and oranges.

My experience is with VAC Motorsports in Philadelphia. They are local to me. I’ve been there many times. I’ve talked to their engineers and actually saw them manufacture the monoball bushings and install them on my car. (It’s not a regular thing. I got lucky with the timing that day.)

The F30 chassis is plagued with very vague steering. When the F-Series was released the automotive press jumped all over it and made the incorrect assumption that it was due to the electronic steering that BMW had upgraded to. BMW ignored it and never corrected them.

Over 10 years later people are still repeating this misinformation. The actual culprit is the huge cylindrical fluid filled bushings that BMW used in the F30 control arms to try to soak up Noise Vibration Harshness (NVH) from the road and prevent it from entering the cabin. The spacing inside those bushings are too great, which causes slop that makes the steering vague.

Track type solutions like harder polyurethane bushings add a lot of NVH so they harsh the ride. The beauty of VAC monoballs is that they have tight internal tolerances that make the steering precise. But since the monoball has freedom of movement in the other directions, no added NVH makes it to the cabin.

Note: Some people inaccurately claim that they feel some added NVH with VAC monoball control arms. But the cabin occupants feel nothing like they would if it was NVH. The VAC monoballs actually transmit an increased road feel through the steering wheel to the driver’s hands. That’s exactly what one would expect. The vague steering goes away and is replaced by a very precise steering feel like one would expect in a European sports sedan.

A weekend tracker told these great story about how his driving instructor kept encouraging him to get closer than 3-4 feet from the straightaway wall to find the best line to enter the next turn. With the stock F30 bushings the steering was so vague that he feared getting any closer to that wall at high speed. After he installed VAC monoball control arms, the steering felt so precise that he had total confidence getting closer to that wall to find the correct corner entry point.

When I first got my VAC monoball control arms, instead of feeling like the car was wandering a bit side to side in the lane, the precision was so awesome that it felt like you could put a stack of dimes on the lane line and I could just nick it if I wanted to..

I don’t comment on other monoball brands. VAC is an engineering, design and CNC manufacturing company that has been creating products for their BMW racing division for decades. Racing is in the VAC culture so the design specs and tolerances that they manufacture to are way above street grade products. The monoball bushings are made on a $750,000 CNC that is calibrated to a thousandth of an inch.

I heard about the VAC monoball control arms almost four years ago from a local guy with an XDrive like mine. He met some VAC engineers at local race tracks and ended up beta testing their monoball control arms. Mine were from their first production batch. Since them I have recommended them to dozens of guys who have all come back with very positive experiences.

The only guy that I’ve ever heard say anything negative about the VAC monoball control arms NEVER actually had them on his car. He eventually admitted that he tried a totally different brand of monoballs that he hated, assumed incorrectly that monoballs are a generic part, and then started ranting as if he had actually tried VAC and had problems, which never actually happened! I tell this story because I’m sure people still run across his old posts based on total misinformation that he basically made up.

I’ve read negative experiences with other brands of monoballs, but I can only tell you my experience with VAC monoball control arms which has been stellar.

Hope this helps!

[Alarbus]

Phil, if you're in the Greater Philly area, call VAC and talk with them about what you want. I had them install their monoballs in my 335, and it's great. Except for driving it back to back it makes my stock F36 kind of flabby. :P

But VAC builds race cars and engines as well, if you're local they're a great shop and resource. Not cheap, but very good.

(Hilariously, SKF's US office is up the blue route in the Lansdale area, so like 30-40 miles north of VAC)

[Boostedphil698]

Originally Posted by Alarbus

Phil, if you're in the Greater Philly area, call VAC and talk with them about what you want. I had them install their monoballs in my 335, and it's great. Except for driving it back to back it makes my stock F36 kind of flabby. :P

But VAC builds race cars and engines as well, if you're local they're a great shop and resource. Not cheap, but very good.

(Hilariously, SKF's US office is up the blue route in the Lansdale area, so like 30-40 miles north of VAC)

I will have to give them a call. I was looking at them for a motor build but Typseed does VERY good work so they've been my go to for large modifications. Funny you mention SKF, I interviewed at that office about two years ago but decided to remain in aerospace work and took a job down the road with Cobham.

[Boostedphil698]

Originally Posted by johnung

People make the mistake of hearing the word “monoball” and assuming that it’s some generic off the shelf part. It’s not. There are a handful of brands that are designed and manufactured differently. They are apples and oranges.

My experience is with VAC Motorsports in Philadelphia. They are local to me. I’ve been there many times. I’ve talked to their engineers and actually saw them manufacture the monoball bushings and install them on my car. (It’s not a regular thing. I got lucky with the timing that day.)

The F30 chassis is plagued with very vague steering. When the F-Series was released the automotive press jumped all over it and made the incorrect assumption that it was due to the electronic steering that BMW had upgraded to. BMW ignored it and never corrected them.

Over 10 years later people are still repeating this misinformation. The actual culprit is the huge cylindrical fluid filled bushings that BMW used in the F30 control arms to try to soak up Noise Vibration Harshness (NVH) from the road and prevent it from entering the cabin. The spacing inside those bushings are too great, which causes slop that makes the steering vague.

Track type solutions like harder polyurethane bushings add a lot of NVH so they harsh the ride. The beauty of VAC monoballs is that they have tight internal tolerances that make the steering precise. But since the monoball has freedom of movement in the other directions, no added NVH makes it to the cabin.

Note: Some people inaccurately claim that they feel some added NVH with VAC monoball control arms. But the cabin occupants [...]

Excellent write up John! Thank you.

[Runner340]

I installed the 4 arm VAC monoballs for PM on my 340ix a few weeks back before the OEM arms started to leak. Going with monoball contol arms is not cheap no matter who you go with. I went with VAC because they are in the USA. Second the FaRKle0079 youtube camber plate comparison gave me pause with Millway quality because their camber plate monoballs have been known to prematurely wear out. I have no regrets going with the VAC monoball arms for normal street use. Steering precision is more on point and the front suspension handles road irregularities better.

[toxik]

Originally Posted by Runner340

I installed the 4 arm VAC monoballs for PM on my 340ix a few weeks back before the OEM arms started to leak. Going with monoball contol arms is not cheap no matter who you go with. I went with VAC because they are in the USA. Second the FaRKle0079 youtube camber plate comparison gave me pause with Millway quality because their camber plate monoballs have been known to prematurely wear out. I have no regrets going with the VAC monoball arms for normal street use. Steering precision is more on point and the front suspension handles road irregularities better.

I believe Millway updated the design in 2022 to address those failures, and even Farkle in his video says he likes their street version camber plate with Poly bushings that would avoid the premature wear.