[Mr. 5]

For those interested in my write up, click the following link:
http://www.e90post.com/forums/showthread.php?t=419570


Tools Needed

-5.5mm Hex wrench
-Car Jack and Support (Jack Stands)
-Breaker Bar with 17mm Socket
-Torque Wrench


Step 1
Look at your old ugly Lugs.



Step 2
Use your breaker Bar to crack loose all of the lugs so you don't have to deal with the wheel spinning while it's lifted in the air.



Step 3
Once you crack all of the lugs loose, Jack up the car and support.





Step 4
Take off all of the Lugs and take the wheel off.



Step 5
Use the provided Loctite and apply to the studs.



Step 6
Install the studs by using a 5.5mm hex wrench. Just make sure they are snug.





Step 7
Once all studs are installed....



Admire how you can put the wheel on without using your foot to hold the wheel on.



Remember this? You can kiss this goodbye!!
I hated doing this every time I changed my wheels!



Step 8
Now install all of the nuts and snug them down hand tight.





Step 9
Once all nuts are installed and snugged down, remove your support and lower the jack slowly.



Step 10
Torque them down. I use 90 ft lbs.



Step 11
Repeat steps 1-11 for your other 3 wheels.

Step 12
Admire your new Macht Schnell stud kit!!









My Dog Loves Them!!

[NiVeDh]

Very good DIY. Great detail and nice pictures. I'm sure the stud kit is very convenient.

However, in your expert judgment, would you not agree that these seem less safe than regular lug bolts? As an engineer, a few things bother me about the stud kit.

I don't know if I trust how the studs are threaded into the hub - the efficacy of Loctite comes into question among other factors. Also, there are now more points where potential failure could occur. Do you think when you torque the nuts, it actually causes the studs to also torque down into the hub?

It's probably not a big deal for a street driver but you're renowned for your track experiences where the wheels will be experiencing different and oftentimes stronger forces, so just something to be wary about. I could be wrong but I don't really see these being stronger than lug bolts.

[forza1976]

I'm shocked these studs only require hand tight. my studs were required to be torqued to 50 ft/lbs before fitting the wheels and lugs.

[Mr. 5]

Originally Posted by NiVeDh

Very good DIY. Great detail and nice pictures. I'm sure the stud kit is very convenient.

However, in your expert judgment, would you not agree that these seem less safe than regular lug bolts? As an engineer, a few things bother me about the stud kit.

I don't know if I trust how the studs are threaded into the hub - the efficacy of Loctite comes into question among other factors. Also, there are now more points where potential failure could occur. Do you think when you torque the nuts, it actually causes the studs to also torque down into the hub?

It's probably not a big deal for a street driver but you're renowned for your track experiences where the wheels will be experiencing different and oftentimes stronger forces, so just something to be wary about. I could be wrong but I don't really see these being stronger than lug bolts.

I'm not saying that they are stronger. I am saying that they are jsut as strong. And, yes, I agree that when you are comparing tightening lugs at X amount of tourque and then comparing tightening down the nuts to X amount of torque, there is the same pressure between the hub and the nut/lug.

Another way to think about this is... take a lug and then screw it into the hub with no wheel installed. You'll find yourself screwing in the lug farther than if you had the wheel installed. How much torque is on the lug without a wheel installed? Probably about 0 (zero) ft lbs.
Once you involve pressure in between the hub and the lug, then this is what increases the 0 ft pounds to 90 ft pounds.
The same methodology goes with the studs/nuts.

[Mr. 5]

Originally Posted by forza1976

I'm shocked these studs only require hand tight. my studs were required to be torqued to 50 ft/lbs before fitting the wheels and lugs.

see post above but this is what I also said in your other post:

Yikes man! You are using an alan wrench to tighten those to 50 ft lbs?
Are you sure it wasn't 50 inch bls? lol

Here's a pdf from Turner that says to tighten the stud kit to 16 ft pounds.
http://www.turnermotorsport.com/imag...structions.pdf

You know, I should edit my thread because people may think of "hand tight" as finger tight so I will make it clearer.
As you can see, I am using a socket wrench to snug them down and are probably around 16 ft pounds.

[forza1976]

See my post in your other thread, seems two separate approaches for keeping them tight.

[John_01]

Regarding the engineers comment, I'd like to offer my opinion: I think that studs and conventional lug nuts are superior to the factory lug bolts due to the effects of loading and stress concentration right at the point where the lug-bolt thread goes into the hub. Each time the wheels are changed, the load is cyclically applied to a different part of the lug-bolt thread as the bolts are torqued up. If the lug-bolt is exposed to loads close to its design limit, in my opinion it has a higher possibility of fatigue cracks and the potential failure of the lug-bolts. I'd be interested to know if people have experienced failure of lug-bolts in this way.

The disadvantage of the stud conversion I can see is the thread being more fully exposed to the water and corrosion. On the other hand it is possible to apply pentrating lubricant to the exposed thread if the lug-nuts ever seize onto the studs.

[NiVeDh]

Originally Posted by John_01

Regarding the engineers comment, I'd like to offer my opinion: I think that studs and conventional lug nuts are superior to the factory lug bolts due to the effects of loading and stress concentration right at the point where the lug-bolt thread goes into the hub. Each time the wheels are changed, the load is cyclically applied to a different part of the lug-bolt thread as the bolts are torqued up. If the lug-bolt is exposed to loads close to its design limit, in my opinion it has a higher possibility of fatigue cracks and the potential failure of the lug-bolts. I'd be interested to know if people have experienced failure of lug-bolts in this way.

The disadvantage of the stud conversion I can see is the thread being more fully exposed to the water and corrosion. On the other hand it is possible to apply pentrating lubricant to the exposed thread if the lug-nuts ever seize onto the studs.

Don't you think the point where the stress is concentrated for the stud where it goes into the hub is more prone to failure than a lug-bolt which has the load applied in a somewhat more distributed fashion? I'd expect that fatigue cracks aren't nearly as lethal as the stud snapping/shearing off or loosening from the hub. I feel like too much is riding on the stud-to-hub interface (literally and figuratively). Maybe a real (mechanical) engineer can chime in (qualifier: I'm a nuclear engineer).

[John_01]

Originally Posted by NiVeDh

Don't you think the point where the stress is concentrated for the stud where it goes into the hub is more prone to failure than a lug-bolt which has the load applied in a somewhat more distributed fashion?

I agree there is a stress concentration where the plain section of the stud end and the threads start. Certainly thats a valid point. I am thinking more about aspects related to uneven loading on the lug-bolts, as I'd expect they will be loaded quite differently every time they are fitted. The studs are permenantly fixed and may not be subject to the same variations. I did a degree in mechanical engineering, but it dosen't qualify me to give an authoritative answer here.

[roadkillrob]

Why are they 2 inches too long?

[lpphreakx06]

HOly education dropping, honestly with the miles MR.5 probably puts on the street and on the track we'll see in no time how durable/safe it is.

[lpphreakx06]

Srsly I love that dog.

[Mr. 5]

Originally Posted by lpphreakx06

Srsly I love that dog.

Thanks man!
I love him too!

[Mr. 5]

Originally Posted by John_01

I agree there is a stress concentration where the plain section of the stud end and the threads start. Certainly thats a valid point. I am thinking more about aspects related to uneven loading on the lug-bolts, as I'd expect they will be loaded quite differently every time they are fitted. The studs are permenantly fixed and may not be subject to the same variations. I did a degree in mechanical engineering, but it dosen't qualify me to give an authoritative answer here.

Alright, I just talked to the head Mechanical Engineer of my department and it's exactly as I thought.
Once the stud is installed and the nut is torqued over the wheel to X amount of torque, this will be EXACTLY the same as X amount of torque on a lug installed (and vice veersa). The stud will stretch the same as the lug which will create a tight lock on the wheel.

The only issue that came to his mind is removing the studs because there is the possibility that the stud will back out of the hole while removing the nut. But...This is what the loctite and torqe settings are for when installing the studs.
I have already taken my wheels off 2 times since I've installed the stud kit for tire changes and brake changes and have had no issues whatsoever with the studs backing out.
I hope this clears things up.

[John_01]

Mr 5, Thanks for your DIY and following up techincal issues. Its appreciated!

I like the idea of stud conversion, but haven't quite found the motivation to do it yet. I'm still using the BMW security bolt on my wheels, so I'd need to find an alternative solution for security.

[EVO_S4]

nice mods and very easy diy, using the RSD on my since it was about $50 cheaper

[Mr. 5]

Originally Posted by John_01

Mr 5, Thanks for your DIY and following up techincal issues. Its appreciated!

I like the idea of stud conversion, but haven't quite found the motivation to do it yet. I'm still using the BMW security bolt on my wheels, so I'd need to find an alternative solution for security.

No worries man!
The compliments keep on coming too.
People have come up to me saying, "Nice wheels. Oh wait, are those studs stock? Those looke really cool!"

Not exactly that but something of the sort.

[scottp999]

Mr5 - Love the wheels. I want them. What are the offsets and what size tires? I can read the rear tire, but not the fronts.

Thanks for the DIY!

[Tallest]

are these lug sets only used for people who swap rims often? It seems that if someone wanted to steel the rims, this would be the easiest way. I don't presume there are some security bolt like solution for people using stud kits?

[bavarianlover]

Great job! How did you comlete the foglight delete on the m3-front?

[ht4e]

Originally Posted by Mr. 5

Alright, I just talked to the head Mechanical Engineer of my department and it's exactly as I thought.
Once the stud is installed and the nut is torqued over the wheel to X amount of torque, this will be EXACTLY the same as X amount of torque on a lug installed (and vice veersa). The stud will stretch the same as the lug which will create a tight lock on the wheel.

The only issue that came to his mind is removing the studs because there is the possibility that the stud will back out of the hole while removing the nut. But...This is what the loctite and torqe settings are for when installing the studs.
I have already taken my wheels off 2 times since I've installed the stud kit for tire changes and brake changes and have had no issues whatsoever with the studs backing out.
I hope this clears things up.

https://www.apexraceparts.com/media/...structions.pdf
a different torque amount using double nut, I am assuming using a double nut to torque vs. just a torque wrench directly torquing the studs to hub to 22 lb-ft is different.

I am an engineer but far from an ME. if I remember my physics class correctly, the 16 lb-ft torque to the stud to hub and the sum of the 90lb-ft. of nuts to the studs turned out to be 106 lb ft?
Is that why it is the same as torquing the oem lug bolts to the torque spec?