vtl's Alpine White 135i

[vtl]

Lower shock eye completed, thanks to my coworker who has a mini mill.

The flat will accept the shaft, and has a locating hole that will be used to align the parts for welding. Very happy with how the parts turned out

Next step will be to remove the shocks from the car, then remove the stick lower shock mounts. Then measure up the threads and determine the correct length for the custom shock mount.

[ekkathewrekka]

Looks really clean for a DIY job

[Aus335iguy]

Looks great Vince

I love machining/milling/metal working for this exact reason.
You take a lump of something and turn it into something that's not only useful but aesthetically pleasing. If it was as lucrative as my current job I would never leave it

[vtl]

Removed shocks from the car so I could get the lower shock mounts removed.

The KW competition rear shocks have a shock mount that is threaded onto the shock. It has some flats milled into it so it appears it can be unscrewed with a spanner. Unfortunately these are pretty stuck on and no way I could get a good enough grip on the shock body to undo the lower mounts.

I decided to TIG weld a nut onto the lower shock mount, and use an impact gun to get them off. This is risky as it is pretty much a one way trip. Luckily, this worked brilliantly and the lower mounts were gunned off with ease! I saw a lot of Loctite remnants so that explains why I couldn't get them off by hand.

Have taken the opportunity to compare to an M3 EDC shock so I can get the shock length correct, then I will fine tune the shock travel with bump stop spacers. I have come up with a new drawing so I have all the dimensions I need to complete the project.

[vtl]

Cleaned up the M3 rear camber arms and got measurements from them. I ended up buying these from Schmiedmann (they also sell used stuff) and european winters are quite harsh on car parts. Took a while to clean up with a wirewheel but looks a lot better now.

To accept the ball joint in the shock mount, I'll need to machine up some M12, 6mm thick washers, not too difficult.

[vtl]

Machined up the shafts for the lower shock mount. The length was carefully selected to adjust the droop and shock travel. i can then fine tune the shock travel with varying the length of the bump stop or adding in bump stop spacers.

To aid assembly, I handed the parts to my coworker to mill some flats into the shaft, similar to the standard part. This will allow me to install the shaft into the shock with a 21mm spanner.

[vtl]

All parts came in for the rear monoball project!

We ended up getting 17 people in total for the monoball group buy, and with that amount of quantity we decided to get the custom washers manufactured by CNC. Got the parts at the end of last week and they turned out fantastic. The washers were made to the design specs out of stainless steel, so will be strong and resistant to corrosion.

Due to the fact that the thickness of the washer would change the geometry of the suspension slightly, I have calculated that the joints must be installed 3mm offset to maintain the factory geometry. This is fairly easy with a hydraulic press and using a pair of digital calipers.

Very happy with how this project turned out, just need to get these things installed.

[vtl]

Some progress on the rear m3 shock mount conversion


I had troubles with a low quality die I purchased, so it ended up chewing up the part and ruining it! I ended up having to tig weld the part to build the material back up, and remachine the shaft again.

I also had troubles with the replacement die I received. It cut the threads very nicely but it had a lead in chamfer on both sides of the die. The chamfer is to allow the part to start easily but usually the opposite side has no chamfer, to allow you to use the die to thread all the way to a shoulder.

After visiting 2 stores and not having the obscure M16x1.0 size, I ended up machining the die I had to remove the chamfer. Was a real pain but got the part done finally.

Next step is to weld the parts then get them nickel plated.

[vtl]

Will be chipping away at the rear monoball install over the next week.

Having installed these on another car recently, I decided to make a bespoke tool for this job, as the universal tools were difficult to use in the small space near the trailing arms. On the first install, I dropped the subframe to allow the tool to fit onto the trailing arm joint on the subframe, this required the subframe to be dropped an excessive amount (to clear the fuel tank) and wanted to avoid that annoyance. Additionally the trailing arm joint on the knuckle is quite close to the brake disc, and removing the brake disc is required if the tool doesn't fit in the space. The rear brake disc is commonly siezed on cars that are parked out in the elements or near the beach (salty air).

I decided to tackle the trailing arm joint on the subframe side first, I cut some of the bushing cups from my universal kit with a bandsaw, and then machined up some steel end caps, welding them onto the cups. I bored out the end caps to allow the threaded rod to pass through. I reused the nut with the thrust bearing from my universal kit. These nuts really help reduce the turning friction and make installation a lot easier with hand power. I made the tools much more compact than the universal tools and it fit in the tight space near the fuel tank no issues.

The bushes pressed out easily and the new ball joints pressed in without any issues. One tip is to file a light shamfer on the leading edge of the bushing so it starts and presses in straight, this was a real problem on the prevous installs and this chamfer really makes it start 100% easy everytime.

Next up will be the trailing arm joints in the knuckle...

[vtl]

Outer trailing arm joints in, I had to add some parts to my custom tool. The space between the ball joint and brake disc shield is very close and does not allow the cup to fit.

So I used an old wheel bearing race as the cup (very low profile) and machined up an end cap to suit it. I put locating features on all the edges so everything locks together and prevents misalignment.

The ball joints went in without issue and was a breeze with the good tools. I had tried a different setup before where the cups and spacers were free floating and not locked together, which resulted in the ball joints being pulled in crooked.

I am impressed with the results, these trailing arms must be a source of significant deflection, and have found the rear end to be significantly stabilized. Up next will be the monoballs in the upper two control arms.

[vtl]

Having converted the rear shocks to use standard upper shock mounts, I decided to make up a supporting plate for the shock mount that is the correct diameter. Previously the KW competition plate was a much smaller diameter so the full face of the shock mount wasn't supported.

I started off with a stainless sanitary end cap (used in food/liquid industrial equipment), and machined them to suit my application.

[vtl]

Finished machining up the custom lower shock mounts.

I made the locating dowels used to locate the parts together while welding, this eliminates any human error lining up the parts.

I also want the compression damping adjusters to face towards the rear of the vehicle, to allow easy adjustment. It is then important to tighten down the shafts into the shock, then weld the outer race of the ball joint in the correct orientation.

I took this a bit further, and tightened the shafts to the shocks. Then, shaved the contact face of the shafts until the flats lined up to the adjusters. This means the new parts will be fully symmetrical and look perfect.

The parts are now fully machined and ready for welding. I will set this up on the rotary table for semi autonomous welding for a nice finish.

[vtl]

More progress on the lower shock mounts

TIG welded up the two lower shock mount parts together, not 100% with the appearance of the welds but should work fine.

Got rid of the oxidation with a scotch pad wheel, and will chemically clean it before plating it. I have ordered an electroless nickel plating kit and will see how it goes.

[vtl]

Found some time to install the Monoball arms.

I ended up deciding to order a new pair of upper control arms and pressing out the joints in the guide rods currently attached to the car. They are not too expensive to buy new and I figured why not just use new/lower kms parts instead.

Have done the trailing arm joints last week, these definitely add another step of rear end stability. Prevously the car would wiggle slightly when thrown into a corner, but now its a bit more planted and doesn't move around. Overall I think this rear end monoball project exceeded expectations, from the reading on the forums I was expecting it to be a small percentage change but I could feel the benefits straight away, even without having to drive the car very hard.

[vtl]

The monoball ball joints that I will use for the lower rear shock mounts are 12mm narrower than the original M3 shock mounts. This means I need adapter spacers to make them fit.

I made them out of 6061 aluminium, they're a bit tricky to make as theyre small parts that are difficult to hold. I ended up making a fixture to do them, quite time consuming for just some washers.

This should be the last bit of machine work needed, just need to nickel plate the shock mount eyes and press these ball joints in and assemble.

[vtl]

Walnut blasted the car, it has been 68k kms and 3.5 years since the last one

The buildup was not too bad in volume but was quite stuck on. Would be a bit easier if the car was warm to soften it though.

The car is slightly smoother on partial loads and idle which is nice.

[vtl]

I purchased an electroless nickel kit from Jane Kits:

https://janekits.com.au/products/ele...trate-1-litre/

The process requires the parts to be thoroughly cleaned and stripped of any oils or contamination. I used a stainless container and heated the solution to 90 degrees C with the stove, it was fairly easy to keep it at that temperature. Used a multimeter thermocouple for the temperature measurement

The nickel plating process takes around 1 hour. The datasheet says around 12-15 microns of thickness per hour. I ended up plating the parts around 1.5 hours. This thickness was also reflected in the measured bore size change too.

The finish was excellent, and I was impressed with the results. The nickel plating results in a bright silver satin finish with a tinge of gold.

I have pressed in the ball joint in and fitment was spot on, along with the fitment in the camber arm. Very excited to fit these into the car, only missing parts are the longer bolts required for the M3 camber arm (ordered and in transit).

[Brule]

Thats some scientific stuff going in. Love it.

[Aus335iguy]

If the cops come around theyre gonna think your running a meth lab!

[vtl]

Originally Posted by Aus335iguy

If the cops come around theyre gonna think your running a meth lab!

[johnny135]

That nickel plating looks awesome!

[vtl]

At 221k kms, my valve cover is finally leaking in my ownership. I think that is a pretty good run. It is still on the original valve cover (evidenced by the original stickers) and the gasket was really stuck on upon removal. I took the opportunity to clean up the top of the cylinder head of all the accumulated oil and dirt.

I replaced the valve cover with a new one, lucky I did, as the old one was super brittle and a few taps of the mallet to unseal the gasket was enough to break off protruding features of the valve cover with very little force.