[B58 _gran_coupe_]

Just looking at options but I'm pretty confused.

Does anyone know compatibility between f30 and f32 and f36 arms?

I know that monoball are the best option but will upgraded bushings serve the same purpose on a road car?

M car arms push the wheel forward so is this dialed back with an alignment?

I've seen these Megan racing arms but are these monoballs or just bushes?



Has anyone upgraded on an f36 and what did you get?

[alohasurftoad]

i was seriously thinking about the megan's because the price for all four is less than the price of just the upper or lower, VAC arms.

you are welcome to "take one for the team" and try the megan's, so all of us on the board may benefit from it, lol.

[B58 _gran_coupe_]

Originally Posted by alohasurftoad

i was seriously thinking about the megan's because the price for all four is less than the price of just the upper or lower, VAC arms.

you are welcome to "take one for the team" and try the megan's, so all of us on the board may benefit from it, lol.

I actually ordered them last night then read they were a bit of a ricer brand so canceled the order lol.

I also discovered that the f3X cars seem to have the same part numbers for the various control arms so aftermarket should be mostly compatible.

I will probably end up with buying turner monoballs or VAC and not risk these disintegrating or bending. They're probably fine but now it's in my head they are of questionable quality.

[danb1979]

Why do you feel you need monoball arms? Serious question; as for a road going car, they'll create more noise and feedback which you'll hear and feel...

Sreten of M539 fame did this on his E39 M5 and soon went back to OEM Lemforder arms due to these very issues

Absolutely get the idea if you're going to really lower the car and want the camber etc; but for an every day car; I'd stick to OEM spec personally

Aren't the M3/M4 arms the ones to go for; for more camber adjustment but retaining the OEM compliance?

*** Edit: Forgot to say that my motorsport mechanic pals use these when they're working on non-M F3x cars that are to go on track/lowered a lot, and they can get really good fast road set-ups dialled in using the M3/M4 arms and they don't push the wheels that much at all...

I chose not to go for them on my F31 as it's an every day driver & I wanted to retain the comfort/ride characteristics of the OEM factory car; so stuck with all new arms and suspension all round and that's made a superb change to the car/handling/ride etc

[B58 _gran_coupe_]

Originally Posted by danb1979

Why do you feel you need monoball arms? Swerious quyestion; as for a road going car, they'll create more noise and feedback which you'll hear and feel...

Sreten of M539 fame did this on his E39 M5 and soon went back to OEM Lemforder arms due to these very issues

Absolutely get the idea if you're going to really lower the car and want the camber etc; but for an every day car; I'd stick to OEM spec personally

Aren't the M3/M4 arms the ones to go for; for more camber adjustment but retaining the OEM compliance?

Good questions. I recently upgraded the turbo and the car has almost 2 x factory power output. I just feel like it's not quite as sharp and connected as I would like it to be.

My friend added monoball thrust arms to his 2018 stage 2+ and as it had covered only 20k miles, he said the difference was not that much.

I also read about the NVH being an issue with polybushed cars and sometimes I read it's not.

I know m cars do not have bushes on the suffrage at all and they aren't that bad.

The car rides like a dream now. It's on bilstein b4 and h&r sport springs and I replaced all of the components when I made that swap.

It's just not as sharp as I would like when I'm attacking the throttle.

It's not a daily currently but I'd hate to scre screw up the enjoyment of driving it.

I know people install m car front arms but it adds caster as well as camber and I'd rather have straight line stability than cornering if I have to sacrifice one for the other.

[rlesko]

Monoball control arms on their own should not introduce unacceptable amounts of NVH. They're quite well suited for the F3x platform over a rubber bushing. And as you stated, they will introduce less NVH than a polyurethane bushing would.

As far as brands go, there is millway, turner, dinan, VAC in addition to many others. I honestly don't really know whats the difference between all of them, though I've read that not all designs are the same.

[co_440i]

Originally Posted by danb1979

Why do you feel you need monoball arms? Serious question; as for a road going car, they'll create more noise and feedback which you'll hear and feel...

Sreten of M539 fame did this on his E39 M5 and soon went back to OEM Lemforder arms due to these very issues

Absolutely get the idea if you're going to really lower the car and want the camber etc; but for an every day car; I'd stick to OEM spec personally

Aren't the M3/M4 arms the ones to go for; for more camber adjustment but retaining the OEM compliance?

*** Edit: Forgot to say that my motorsport mechanic pals use these when they're working on non-M F3x cars that are to go on track/lowered a lot, and they can get really good fast road set-ups dialled in using the M3/M4 arms and they don't push the wheels that much at all...

I chose not to go for them on my F31 as it's an every day driver & I wanted to retain the comfort/ride characteristics of the OEM factory car; so stuck with all new arms and suspension all round and that's made a superb change to the car/handling/ride etc

Most people who get VAC monoballs on here do not report a noticeable change in NVH but a dramatic increase in steering precision and feel, just from posts on here it seems less than 5% report what you’re claiming. I have mine and am waiting to install them.

[danb1979]

Apologies; should have said that its from experrience here in the UK where our roads are horrific at best and not comparable to the roads in the US

We've very narrow, tight/single track at times, windy country roads that are uncared for; raised manhole covers, potholes in potholes etc

Not a place for monoball suspension etc...

I've experienced it personally on numerous Jap import Honda's I've owned; never in a BMW I've owned. But I've pals that have M3s and M4s and have done the monoball arm conversion only to go back after a few weeks as they were great on the faster, better roads; but horrendous on the country lanes etc

Our roads are getting worse and worse; councils are cheap and will not do whats needed and fix the roads; they've always an excuse as to why they've no £££ etc

[fortythirtyfive]

Originally Posted by B58 _gran_coupe_

M car arms push the wheel forward so is this dialed back with an alignment?

Nope, you would need caster offset bushes to fix that.. the problem there is you're then removing the spherical bushing that BMW M put in their M arms, whilst you'll gain a tiny bit of camber you'll be still stuck with a hydrofilled bush.

The only people I have seen successfully running M arms are on either 18" wheels with a super conservative offset, i.e no spacers or aggressive wheels.

[rlesko]

One additional comment wrt M control arms - I personally wouldn't do it, but if you do I'd get M tie-rod ends as well. The F3x tie rods are barely threaded with the additional length of M control arms. You will gain caster too... But I also think that slapping M parts on the F3x chassis isn't just something that leads to universally "better" results

[alohasurftoad]

Originally Posted by rlesko

One additional comment wrt M control arms - I personally wouldn't do it, but if you do I'd get M tie-rod ends as well. The F3x tie rods are barely threaded with the additional length of M control arms. You will gain caster too... But I also think that slapping M parts on the F3x chassis isn't just something that leads to universally "better" results

+1

i dislike how M-arms caster pushes the tire forward from center and changes the geometry

[B58 _gran_coupe_]

Appreciate the feedback. I'll probably shoot for the VAC f3x monoball arms and be done. $1200 for the set though....ouch!

Thinking about the road (yellow powerflex) rear subframe bush inserts and the differential inserts. I just hope the accumulative rigidity doesn't make the ride unpleasant. This car will probably never see a racetrack.

If I do it all in a weekend then it will be one and done for the alignment.

[alohasurftoad]

Originally Posted by B58 _gran_coupe_

Appreciate the feedback. I'll probably shoot for the VAC f3x monoball arms and be done. $1200 for the set though....ouch! Thinking about the road (yellow powerflex) rear subframe bush inserts and the differential inserts. I just hope the accumulative rigidity doesn't make the ride unpleasant. This car will probably never see a racetrack. If I do it all in a weekend then it will be one and done for the alignment.

i didn't align after i installed my vac arms because the suspension geometry doesn't change. however, i understand if you need to for you peace of mind...

[B58 _gran_coupe_]

Originally Posted by alohasurftoad

i didn't align after i installed my vac arms because the suspension geometry doesn't change. however, i understand if you need to for you peace of mind...

Yeah I guess the geometry will be the same. I'll probably fit them then see. I'm really weird about tires and alignment so I'll probably have it done for peace of mind like you suggest

[johnung]

Originally Posted by danb1979

Why do you feel you need monoball arms? Serious question; as for a road going car, they'll create more noise and feedback which you'll hear and feel...

Sreten of M539 fame did this on his E39 M5 and soon went back to OEM Lemforder arms due to these very issues

Absolutely get the idea if you're going to really lower the car and want the camber etc; but for an every day car; I'd stick to OEM spec personally

Aren't the M3/M4 arms the ones to go for; for more camber adjustment but retaining the OEM compliance?

*** Edit: Forgot to say that my motorsport mechanic pals use these when they're working on non-M F3x cars that are to go on track/lowered a lot, and they can get really good fast road set-ups dialled in using the M3/M4 arms and they don't push the wheels that much at all...

I chose not to go for them on my F31 as it's an every day driver & I wanted to retain the comfort/ride characteristics of the OEM factory car; so stuck with all new arms and suspension all round and that's made a superb change to the car/handling/ride etc

Your opening statement is incorrect. “they'll create more noise and feedback which you'll hear and feel”. That may be true of one manufacturer, but monoballs are NOT commodity items. Each monoball design differs. Speaking about monoballs in broad generalities just spreads misinformation.

The design of a proper monoball bushing such as VAC’s accomplishes two things:

1) A well designed monoball eliminates the excess internal play in the stock bushings of the front control arms that cause the vague steering of the F3x. In comparison with VAC monoballs, the steering is much more precise.

2) A more solid bushing would transmit more Noise Vibration Harshness to the cabin as you describe. The whole point of the ease of movement of a monoball in all directions is that it deflects, which actually prevents the transmission of NVH to the cabin.

The VAC monoballs do add a little more road feel that is transmitted to the driver’s hands through the steering wheel. It is definitely an improvement. Some people have incorrectly described it as NVH transmitted to the cabin which it is not. Passengers cannot feel or hear it.

[johnung]

Originally Posted by B58 _gran_coupe_

Just looking at options but I'm pretty confused.

Does anyone know compatibility between f30 and f32 and f36 arms?

I know that monoball are the best option but will upgraded bushings serve the same purpose on a road car?

M car arms push the wheel forward so is this dialed back with an alignment?

I've seen these Megan racing arms but are these monoballs or just bushes?



Has anyone upgraded on an f36 and what did you get?

Checking compatibility is easy. Just use the realoem website to compare the stock part numbers of the control arms in the different models. If the stock part numbers of RWD F30, F32, F36 are the same then they are compatible. The same goes for the three XDrive models. RWD and XDrive use different control arms so there is no compatibility between them.

[johnung]

Originally Posted by B58 _gran_coupe_

Appreciate the feedback. I'll probably shoot for the VAC f3x monoball arms and be done. $1200 for the set though....ouch!

Thinking about the road (yellow powerflex) rear subframe bush inserts and the differential inserts. I just hope the accumulative rigidity doesn't make the ride unpleasant. This car will probably never see a racetrack.

If I do it all in a weekend then it will be one and done for the alignment.

If money is an issue then install the VAC Upper Control Arms/Thrust Arms first. They have the biggest impact on the steering precision. The Lower Control Arms/Wishbones also improve steering but I’d estimate the impact to be about 50% as much as the UCAs.

I would discourage you from diving in and making changes to the rear bushings, as others discouraged me when I was researching. Friends who track all told me that going to stiffer rear bushings would only worsen my street ride, not improve it. Even a friend who had installed monoball rear bushings told me not to do it. He said that I’d never feel a difference on the street. He said that he did it strictly for the benefits at high track speeds and conditions.

In general when you’re modding it is always better to only change one thing at a time. When you change 2-3 and something doesn’t feel right, it makes things much more difficult to troubleshoot and correct.

[fortythirtyfive]

Originally Posted by B58 _gran_coupe_

Yeah I guess the geometry will be the same. I'll probably fit them then see. I'm really weird about tires and alignment so I'll probably have it done for peace of mind like you suggest

Originally Posted by alohasurftoad

i didn't align after i installed my vac arms because the suspension geometry doesn't change. however, i understand if you need to for you peace of mind...

Not sure about the VAC's but my Millways have a centralised hole for the bolt in the bushing.. oem/standard arms are slightly offset which will be a minor caster change.

I honestly can't remember what the alignment printout was like after, I had it done though because I had taken a whack from a pothole a 2 weeks prior to installing them so the difference wouldn't have been that accurate.

[cfm56d7b]

Originally Posted by johnung

If money is an issue then install the VAC Upper Control Arms/Thrust Arms first. They have the biggest impact on the steering precision. The Lower Control Arms/Wishbones also improve steering but I’d estimate the impact to be about 50% as much as the UCAs.

I would discourage you from diving in and making changes to the rear bushings, as others discouraged me when I was researching. Friends who track all told me that going to stiffer rear bushings would only worsen my street ride, not improve it. Even a friend who had installed monoball rear bushings told me not to do it. He said that I’d never feel a difference on the street. He said that he did it strictly for the benefits at high track speeds and conditions.

In general when you’re modding it is always better to only change one thing at a time. When you change 2-3 and something doesn’t feel right, it makes things much more difficult to troubleshoot and correct.

Suspensions consist of multiple components designed to work together. Changing one component at a time is by far one of the best recommendations.

Generally, components optimized for track duty or racing do not provide added benefits in daily driving conditions. Components which provide daily driving comfort _and_ can be taken to the track are worth considering.

[B58 _gran_coupe_]

Originally Posted by johnung

If money is an issue then install the VAC Upper Control Arms/Thrust Arms first. They have the biggest impact on the steering precision. The Lower Control Arms/Wishbones also improve steering but I’d estimate the impact to be about 50% as much as the UCAs.

I would discourage you from diving in and making changes to the rear bushings, as others discouraged me when I was researching. Friends who track all told me that going to stiffer rear bushings would only worsen my street ride, not improve it. Even a friend who had installed monoball rear bushings told me not to do it. He said that I’d never feel a difference on the street. He said that he did it strictly for the benefits at high track speeds and conditions.

In general when you’re modding it is always better to only change one thing at a time. When you change 2-3 and something doesn’t feel right, it makes things much more difficult to troubleshoot and correct.

I very much appreciate your input here.

If you're being discouraged from the subframe inserts then I'm sure that's for very good reason. What I don't understand is that M cars, to my understanding, have solid subframe bushes and although they feel rougher than non M variants, you don't here of people really complaining about nvh from their M3 and M4s. I've heard people talking about a harsher ride but not a deal breaker for a road car.

[B58 _gran_coupe_]

Don't suppose anyone has a discount code for VAC Motorsports?

[johnung]

Originally Posted by B58 _gran_coupe_

I very much appreciate your input here.

If you're being discouraged from the subframe inserts then I'm sure that's for very good reason. What I don't understand is that M cars, to my understanding, have solid subframe bushes and although they feel rougher than non M variants, you don't here of people really complaining about nvh from their M3 and M4s. I've heard people talking about a harsher ride but not a deal breaker for a road car.

The F3x chassis and the F8x M3/M4 chassis are different cars. The engineering is totally different. They share very few parts. Suspensions have many parts and are designed as a system to work together. People have this idea that if they took a part off an M3 that it would make their F3x better but that’s not the case.