From my understanding the front ball joints are not replaceable is this true? If so what the only way to replace a bad ball joint is to buy a used control arm and hope that they are in better shape?? Has none found a way to replace them without buying a new/used control arm this just seems dumb to me

 

Yes, it's true.
Yes, afaik, that's the only way to replace OEM other than finding a new control arm.
There are these: MOONFACE Super Lap Roll Center Arms Mazda RX-7 FD3S - RHDJapan .
I don't believe the OEM lowers go bad very often under 'normal' use. I know a few owners with cars that have over 150k reporting no issues. Mine still are pretty tight at 120k with a lot of autocross in the past. If the car has been driven by an asshat with ignorantly wide tires, stupid silly wheel off-set, dumb negative camber on moronically bad roads I suppose they might go bad sooner.

 

WOW! $1300 for Control arms?..That's insane!.

Search/Look up a post by: Galvatron10000 (cdn section)
He had ideas about this ball joint issue.I am not sure what the outcome was But I do remember who and what the subject was.


Now..where's my coffee..and my dog...

 

Yea 1300 is nuts that's a 1/3 of what i paid for the car Lol. The ball joint seems good just someone stripped the threads on it

 

I suppose one could carefully measure the stud, and try to find a suitable replacement. I do like how these are serviceable with the zerk fitting, though. I bought the Moonface SuperLap LCAs back in 2014. I finally got the car on the road last year in October, and I like them. Only a couple track days on them, though. I bought the Moonface LCAs and Nagisa UCAs back then. The Nagisa UCAs do rub the stock wheels close to lock, though. Next year, I am planning to get new wheels and tires which should solve that problem. Sorry to derail the thread, but I will give a little review.

First, my car has been professionally set up with full suspension adjustment and corner-balanced. I'm running Megan rear adjustable toe links and trailing arms, and Ohlins DFV dampers. All stock bushings. The Moonface LCAs have been fine so far. The combination of the Moonface and Nagisa is what I have to report. I find the steering to be "twitchy." What I mean is this: Let's say I'm on the highway, tracking straight, and I intend to switch lanes - As I give a little steering input, the car seems to "pull" in that direction until I straighten. Not so much that it hints at control loss, just not the kind of feedback that you get from a typical stock car with fairly "neutral" steering and feedback. It is a track car, though, so it should be aggressive to some extent. Hard to explain the experience, though. The shop that tuned the suspension said that they have setup similar FDs, and they think it's the Nagisa UCAs. I may switch back to stock UCAs at some point, just to see the difference and if I like it.

I do like the prospect of replaceable ball joints, which is the exact reason I got the Moonface LCAs. They have been discontinued, though, which concerns me for replacement ball joints.