[GP79]

Amazing work mate 🤙

 

[Andrew1211]

Looks great! Excited for these

 

[Masera]

Bravo!

 

[lambertius]

Are there any good guides on setting all the correct alignment and placement using the shims? This isn't something I'm familiar with!

Lower arm went well!

 

[navcorr]

Is the wishbone bolt specific to your arm - or did you source an OEM replacement? Curious as someone over here has had to have them made previously.

Re: shims, can't recall seeing anything. Alignment I leave to someone else - preferably with a Hunter.

 

[lambertius]

Is the wishbone bolt specific to your arm - or did you source an OEM replacement? Curious as someone over here has had to have them made previously.

View attachment 144663

Re: shims, can't recall seeing anything. Alignment I leave to someone else - preferably with a Hunter.

I'm currently using the OEM insert but I can can definitely get them made and have a supplier organised for them already for the toe adjusters.

 

[lambertius]

I learnt a lot from the test fit and playing around with the satanic shim system.

One key take away is the bushing removal is an absolute prig and is going to make sustainability difficult. The reason this is so hard is because the flanged surface on the bushing prevents pushing the bushing totally through the arm for removal. Installing the bushings is easy, you just place them in and press them in directly. So, I've been working on a set of press tools specifically designed to reach through the bushings. Below is the upper arm, but there is a longer extension for the lower arm. The idea is that every set of arms would come with the press tools.

This is a really good example of the difference between design and implementation difficulties. Designing the press tools is easy, however they have a maximum load capacity of about 2.5T because they can't be wider than 14mm diameter. If I start using tool steels I could probably push that closer to 3.5T. That should be fine, but after a few years on salty roads the bushings can swell and seize and may require pressing forces close to that limit. Because of the thin nature of the tools the risk of a buckling failure before the failure load is a possibility.

What would be really good to implement is to flip the direction of the bushing so that they're inserted from the other side. From a design perspective this is a gigantic pain because the bushing mounts are my point of reference for all the geometry, and there is an asymmetry to the way they're implemented. In practice it takes a lot less force to insert a clean bushing, and you can use lubricants and clean the surface.

Anyway, this is a ramble about why I'm going to burn a few hours inverting the way the bushings are inserted so that some guy changing the bushings in 5-10 years has an easier job. Every set of arms is going to come with some press tools specifically for inserting new bushings as well.

I've also made some design changes after running a lot more FEA. The arms are much much stronger than the OEM parts.

The last part item on the check list is making new lower subframe mounts so the 3200 can use the arms.

The lower arm now has a minimum failure load of at least double the original arm

There are also no longer any obvious stress focal points.

This is a simulation of the upper arm showing that you could bolt the arm to the wall, dangle 1T from it and expect less than 1mm of deflection. I would really like to put an intentional failure point in them so that they break in an accident and protect the subframe, but that is the sort of stuff you can only do with practical testing and I don't exactly have a few cars for crash testing.

 

[lambertius]

@Jason@ Enzo`s Atlanta Any insights you can share before I lock in the production design 100%?

 

[Jason@ Enzo`s Atlanta]

Man, I know my limitations.. I literally know nothing about that kinda stuff.. I'm in the repair dept. and not in design. Jason

 

[lambertius]

Man, I know my limitations.. I literally know nothing about that kinda stuff.. I'm in the repair dept. and not in design. Jason

That's what I'm asking for - you've been playing around under the car, if there is anything you find problematic or have seen as a recurring issue that I can address, let me know. For me, the one thing that stood out is the bushings are facing the wrong direction for serviceability. I can make other changes if there are things you've come across.

 

[Erik 4200CC]

i cut off the flange of the center part of one of the bushings, after which the center part slides out. After that you can use a wider rod to push onto the other bushing. Maybe you can make the tool easier by just using a simple piece of tube (of the correct diameter) for support, and a rod with threaded ends (and standard nuts, or custom flanges to screw onto the rod) for pushing everything out.

 

[lambertius]

i cut off the flange of the center part of one of the bushings, after which the center part slides out. After that you can use a wider rod to push onto the other bushing. Maybe you can make the tool easier by just using a simple piece of tube (of the correct diameter) for support, and a rod with threaded ends (and standard nuts, or custom flanges to screw onto the rod) for pushing everything out. View attachment 144723

View attachment 144724

I was thinking of doing that, using a hack saw to cut off the top but then I didn't go ahead with it because I didn't realise the part would come apart that easily. I'll think about it for a bit before making any revisions! Thanks for the photos, it helps!

 

[Erik 4200CC]

Mine was very worn out with a lot of play, so maybe not fully representative..

 

[lambertius]

I really only intended to make these for myself, holy balls batman is setting up a company a pain! So much stuff to learn. Anyway, I'll be doing everything I can to make these available through the company, and the company will be getting an ADR engineer to review the parts and a bunch of other liability things.

I've also decided I'm going to implement the tie rods the same way they're implemented on the Trofeo because it is a lot easier to adjust the toe this way. The base model way has a tendency to seize in the arm. I do not understand why they made some of these decisions, like the car is so impressive and such a turd at the same time!

 

[Cdn17Sport6MT]

i cut off the flange of the center part of one of the bushings, after which the center part slides out. After that you can use a wider rod to push onto the other bushing. Maybe you can make the tool easier by just using a simple piece of tube (of the correct diameter) for support, and a rod with threaded ends (and standard nuts, or custom flanges to screw onto the rod) for pushing everything out.

Erik, regarding the hydraulic press (and I don't want to hijack the thread) - but don't you want to employ a safety mesh / hydraulic press personnel guard on your press? If the pieces were to kick out laterally they could kill you...

 

[lambertius]

Erik, regarding the hydraulic press (and I don't want to hijack the thread) - but don't you want to employ a safety mesh / hydraulic press personnel guard on your press? If the pieces were to kick out laterally they could kill you...

 

[lambertius]

When I started this, I just wanted to get my car roadworthy and have a bit of fun in the process. I bought some new lower control arms at a reasonable price, and was only intending to make the upper. Instead I've gone down some insane process trying designing the whole rear suspension setup from scratch to match the OEM parts which has lead me to the conclusion that the original designers must've been smoking the glass barbie. Some of the stuff I've learnt along the way:

-They made the upper and lower arms use different bushings even though they could've used the same for both arms. I'm stuck with this nonsense because I'm making OEM replacements that will take the original bushings.
-They arranged the ball joints the wrong way.
-The toe adjustment is absolutely trash.
-Despite there being lots of components the arms were designed as disposable and not serviceable.
-The early versions of the arms on the 3200 were designed with structural flaws and could suffer catastrophic failure.
-The castings of the OEM parts leaves them susceptible to random failures.

I've put so much more effort into this than I ever intended. Here are some things that might surprise you:
-There are more than 50 components between the two arms.
-I've had to organise manufacturing for components across 5 countries.
-I have needed to setup a specific kind of company structure to make these available for sale (which is finally ready).

I'm only waiting on two things now finally.

-Final quote so I can finalise the production pricing.
-I decided to approach an automotive engineer that the components meet the Australian Design Rules (ADR) for vehicle modifications and to certify them as OEM equivalent of exceeding. There are a bunch of tests and simulations I'm doing for this. Basically the interest was strong enough that I'm ensuring that as director of my new company, I'm doing all due diligence and acting in good faith.

Where I'm at now is that I'm intending to sell the arms in two packages.

1) Complete Rear + Spares
This will be 2 upper and 2 lower arms+ spares and tools fully assembled. It will come with 4 spare ball joints and studs, a full spare set of rear bushings, and the press tools required to change the bushings.

2) Individual Arms
These will come with a ball joint only. It will be up to an individual to source their own bushings. They can chose to reuse their toe rods or buy new ones.

I've also decided to make some performance upgrade options.

1) Trofeo Toe Adjuster

This is designed as a copy of the toe adjustment system on the Trofeo cars. It allows for +/- 7 degrees of toe adjustment quickly. You should never need that much, but it will be a hell of a lot easier to adjust the toe this way. This is using the original SKF bearings in SKF toe ends with a billet adjustment rod.

2) Solid Bushings

The below solid bushings will fit a modified version of the upper and lower arms and will include some spacers for fitment into the subframe.

There will also be some accessories available separately:

1) OEM style toe adjuster
2) OEM style toe insert
3) Bushings
4) Set of custom Press Tools

Below is an FEA model that I'm currently working with the engineer for compliance.

To get this over the line, I need to make a minimum order quantity. If you've been watching this thread and are interested please reach out. The first batch will have a substantial discount applied so that I can make it across the line.

I'm waiting on one more quote and then I'll be back in the next couple of days with the pricing. I'm hoping to start taking orders this week 🤞

 

[lambertius]

I am now ready to take orders. I've broken the pricing into two categories, Complete and Budget based on feedback.

The Full Rear Kit - $7100 USD

-2x Rear Lower Arms (fully assembled)
-Toe Rods and Inserts
-Brake Line Brackets
-Powerflex Bushings
-Replaceable Ball Joints

-2x Rear Upper Arms (fully assembled)
-Powerflex Bushings
-Replaceable Ball Joints

+

-Full Press Tool Kit
-Full Set of Rear Bushings Spare
-4x Spare Ball Joints

Upper Rear Arm Only - $950 USD
-1x Rear Upper Arm
-1x Ball Joint
-Not Assembled
-No Bushings

Lower Rear Arm Only - $1500 USD
-1x Rear Upper Arm
-1x Ball Joint
-1x OEM Style Toe Rod
-Not Assembled
-No Bushings

Press Tool Kit - $1250USD

Pricing isn't complete yet for the Track Pack parts, but it will be very similar.

For Comparison, a single lower OEM arm can cost as much as $4500USD. Though you may find the Upper arm in stock, it is NLA and when it was available it was more expensive than the lower.

Right now, full kit orders will be filled in priority to individual arms. There will be a 20% discount applied to the first few orders required to hit all my minimum order quantities and this discount will only apply to the full kit.

Anyone who is interested, I will talk with directly and I will fill in on some more specific details.

 

[lambertius]

I'm one order away from the MOQ, so if anyone is on the fence - please reach out!

 

[lambertius]

Looks like I've got the MoQ hit!

This week, I'm hoping to get the certification that they meet or exceed OEM done and ADR compliance.