RED MX5

BTW guys, FWIW, XViper won't take part in this thread. He and I have discussed his reasons, and I fully agree with them. However, I assure you, I've discussed this with him, and he's on the same page Bill and I are. Just because we all agree doesn't necessarily mean that we're right, but given the people involved I think the odds of us all getting it wrong fall somewhere between slim and none.

If we are shown to be wrong, and told how to figure out the correct spacing for a given drop (if any such thing exists), then I'll be the first one in line to buy spacers. As it is, I'm more than just skeptical about this mod, but I guess I've already made that all too clear.

tekstar

Good info

RED MX5

This information would be a valuable addition to this thread.

While you're in there, figure out how much the balls move with 1" of suspension movement. We've been told that we need either 7mm or 10mm spacers, and I'd be willing to bet that one inch of movement actually produces far less than 7mm of ball movement.

Bill, pardon the terms I'm using here, but they're descriptive and everyone undestands them, so I'm sticking with them.

If the balls move 10mm total I'll be very surprised.

negcamber

Here is a repost of what I wrote in another thread on this subject:
[QUOTE]
Looking inside the inner cv, it seems there is room to accommodate for a lowered car without a spacer.

RED MX5

You are one of the guys I was including when I mentioned the "wear pattern theory." You, XViper, and other knowledgable people have suggested this as a possible benefit of the spacers.

However, lowering does not appear to lead to early CV joint failure. If it did, my CV joints would be shot. They had 3,6000 miles of wear before the drop, and are now approaching 60,000, so if there was a wear pattern issue I'd have had problems. In fact there is no easy way to show that the wear patterns matter at all (or that they don't matter), and no way to show that a vibration after a drop is actually a result of the drop. More to the point however, if we are to match the old wear pattern we have to have EXACTLY the right spacing, so a choice of 7mm or 10mm doesn't make any sense at all.

I said this before too, but I'll say it again to remind everyone. This "wear pattern theory" is NOT why the guys making the spacers tell us we need them. This theory makes more sense than the one they've been feeding us (at least given our current understanding).

Negcamber, I don't disagree at all with the theory that a pitted CV joint may fail sooner if we change the normal (as opposed to total or static) operating range, for the very reasons you state. However, one-size-fits-all spacers cannot possibly match up the old and new wear patterns, and for that reason the current offerings are a crap shoot at best. Do me a favor and re-read my opening post, and see if I explained this well enough. PM me to let me know what you think.

I totally agree that the CV joint failures are a result of the mileage on the car BEFORE it was lowered, and I will even suggest that they were on their way out anyway. Those pits bump the bearings constantly. With sound CV joints there does not appear to be an issue (and my car is as good an example as I can think of).

FWIW, and I'm sure you realize this, you, Bill(man), Dave (XViper), and that dumb old MX5 guy are all very much on the same page here.

RED MX5

Maybe 10mm is enough to move the balls to a completely unworn part of the cup. If that's the case we've still been given BS justifications for this mod, but running on a new surface would certainly prevent any problems caused by old wear in the cup. Interestingly, if this is the case, then a joint with excessive wear in the cup could be made to work like new by using the spacers and running the balls further in.

That said, re-read what Billman said above. We'll soon know the total movement, and the movement at 1" of suspension travel, and that will be telling. If a drop doesn't push the balls outside of, or to the very edge of, the working range of the joint, then we've been fed a bill of goods regarding the spacers.

s2kSEOUL

54K miles on mine and they need replacement now, not even lowered yet Gotta replace CV's this weekend, if they come in! Can't wait to see what the old ones look like.

This is great info and I am sure everyone appreciates the "myth busting" as much as I do. Now we need one on grounding kits, krank vents, turbonator, etc!

gomarlins3

I have been watching sets of these on eBay for awhile and debating on getting them. This thread has gone a long way to help me make up my mind, thanks everyone.

Billman250

Why waste your money.

Swap the buckets side to side and it will be good as new.

RED MX5

^^^ Damn Bill, I'm getting old. I use to know that, and I just learned it anew.
Getting old is a bitch sometimes.