Made my own CNC offset lower ball joints
 

A while ago I figured out I really needed more front camber for my STR s2k. I did a lot of research and couldn't really find any commercially available offset lower ball joints that were street touring legal. They all were roll center "correcting" in addition to being offset for camber. There were some that didn't explicitly say they were camber only so I ended up buying a set (I think they were EVS but I don't really remember). Turns out they were also illegal. So I finally got around to building my own. They should end up maxed around 3.5 degrees. They're also made of 15-5 PH stainless steel so I can leave them raw and shiny :D

Frick this picture uploader is stupid

https://cimg8.ibsrv.net/gimg/www.s2k...9d31e39e79.png
Here it is
https://cimg5.ibsrv.net/gimg/www.s2k...f5b07b4d55.jpg
Next to a factory mount
https://cimg8.ibsrv.net/gimg/www.s2k...9a4d613968.jpg
Factory stuff and rough stock

OH boy!!!!! I'm loving this nice work !!!

nicely done man!

Thanks guys! I forgot to mention that these also reuse the actual high quality oem ball joints instead of the mystery chinesium joints that are used by all the aftermarket units.

You should market these.

I second that

Actually there is already couple of companies that make these. But nice job for a DIY.

There might be. I got tired of researching the stupid things and their very unspecific marketing.

I highly doubt anybody would be willing to buy these were they available. The price would be astronomical. They take three to four hours to machine for the pair. I could make it much faster but I would likely lose much of that super shine. Plus how many people would want to spend that kind of coin and still have to press out their factory joints and press them back into the new ones?

In my searching I never found one that wasn't roll center correcting. Awesome job!

Why not use offset bushings in the upper A arm?

Because this way widens the track...and plastic bushings are a bad idea....and this way is cooler.

What? Derlrin bushings are used a lot without issue by many. This is way cooler though.

Did you machine these yourself? 3-axis?

For curiousity, what was your final ID compared to stock. Usually press fit features are controlled to 4-decimal places. I've never done anything that accurate on mine and am curious how hard it was to achieve.

Yes I did machine, program, and model these myself. They were made in a 3 axis machine in two ops, both in a vise. They were programmed and modeled in CATIA. If I had to make them again I would definitely build a fixture for OP2. The press fit ID is a very good point. I can't remember what the actual dimensions were but the finished ID ended up being a half thou larger than the oem piece as measured by tri-mics. They are still a press fit with IIRC 0.001 interference but I do plan on assembling with loctite 603 just to be sure. The loading direction actually forces the ball joint into the mount so even a light press fit would probably be ok. If I remade them /i would obviously machine them to the proper size :LOL:

I made these on an Okuma Genos M560. I don't know what kind of machine you're working with but this will pretty reliably profile contour IDs to one or two tenths.

Thanks! Yes the added track width is definitely a nice benefit. There are of course offset upper ball joints as well but they have a bad reputation of slipping.

I finally got around to installing these last week. On my lowered car the camber range was from about 2-5 degrees. Dang they look nice though!

Impressive work. Isn't an Okuma Genos M560 a $120+k machine?

As a sidebar, is the S2k still competitive in STR? At Lincoln, there were 2 in the top 15, the best being in 8th. The rest: MX5 Miatas. Locally, there are many more factors. But are they at the level that a few mm in track matter that much?

Thanks. As for the cost, I'm not sure, I don't get involved too much in the money side of things and all the machine sales. The company I work for is probably going to get another one though, so I'll probably know at some point. It's a nice little workhorse though!

Everything I've read points to the s2000 being a thing of the past in STR. I wouldn't even bother taking mine to Nationals. My car is a good 80-90% build but the last bits are things I don't want to screw around with, since it's the wrong car for the job anyway. It's still really fun locally though.

In STR, the Mazda is 300-400lb lighter on the same rubber and wheels with only a small difference in acceleration. They didn't fare much better in B/Street where BMW M2s seemed to dominate.

Still, a very nice sports car!

This machinist approves :thumbup:

Its our sickness to make things just because we have access to the tech.