FC S4 Custom Ball Joint Experiment
 

Many of us have had to extend our ball joints to allow for more angle without rubbing. One of the hassles of rx7 FC (s4) ball joints is that once the joint goes bad you must replace the whole piece because our joints are not "press in". I am currently working up a joint that is two inches adjustable and has regular press-in joints. The slots also allow for another axis of camber adjustment. The ball joint I will be using is a #K7147 part number.

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Let me know what you guys think, I am pretty excited to get these made and try them out.

great idea dude. i think i need to extend mine... rubbing @ full lock with 18x9.5 -27

I could see welding a washer onto one side once you get it set to where you want it so they never lose the setting. But I like the concept.

I like the concept. Id buy them. Hell ill even buy the first batch

I'll buy them too. You have a price in mind?

The idea is to have two versions. They will be sold as a pair (left and right) including ball joints with a chromoly version for ~ $200 and an aluminum for ~ $250. The renders above are the part in Aluminum.

I'm in. I do road racing stuff so I dont need as extreme of an adjustment.

Perhaps just make it 3 position adjustable for added security and ease of setup.

Is this going to change the roll center at all with that balljoint?

NOTE:Kind Reminder to the OP.

Before this Thread gets Turned Inside out,PLEASE do not start Promoting these Products mentioning PRICE..OR attempt to start a List for members to BUY.

IF you intend on selling them as a Product,then InternetBrands(The Forum Owners) will need to be contacted so you can set up a Vendor account to sell these parts.
Thanks for your co-operation.
STYX (MOD)

Yes definitely, I apologize if I approached any boundaries was simply responding to Turtle13. This was meant to be an input and description thread which is why I had not posted posted prices in the original post. When I start making these joints and I am looking to sell I will definitely be talking to you guys about vendor status.

I would think 3-4 position adjustable would be way better. Maybe .4" - 8" - 1.2" - 1.6" ??

are you sure that ball joint will fit into the hub? the hub pinch mount has an 18mm bore.

we made these for my car and considered making extras if there was enough interest, but they do help a lot and make the car feel way better.

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id be interested too. a 2 or 3 position isn't a bad idea. keeps it from being able to slide out of position if you end up hitting anything

dude that heim is hitting the rotor....

I ran those on my car for a few years without issues until I went to a compeltely custom LCA.

Pats setup is easy to make and I can make more if people want.

I also have an adjuster on there and the holes are slotted so you can go +/- 10mm on the setup very quickly.

^That would be the tie rod...

i was strictly talking about the LCA stuff.

I would be interested in this setup if you guys decide to produce them

You're gonna actually finish the RX7 Brandon?

Yep just putting a few smaller items together.

Changed the design a little since my first post, but I Finally got a set of these made. Testing fitting them. Need to make a few more adjustments before the next set.
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you should really install them on top of the control arm ...

I just dont understand why you want them adjustable. Im willing to bet you/most people will just adjust them out as wide as you can(I.E. look at the picture) then leave them that way.

Why? It makes no difference to the roll center.

It is another way of camber adjustment. If you max it out thats great it will still work fine. But if you dont have all of the other steering parts to benefit from maxing it out you will be able to find your medium. And still have replaceable joints.