I had the Mazdaspeed camber links on my 3 w/Prokit springs.They allowed me to get exactly back to stock specifications camber, caster and toe. The front is fully adjustable. The rear is adjustable except for camber, that's what the links are for.

Before the links my rear camber was -2.1 degrees (-1 is stock), after installing the links I was right back at -1

 

Then what are the eccentric bolts for in therear lower control arms? I've pulled them in (the control arms) and improved my handling, even though I am still on stock springs. It's visually obvious that the rear tires are now flatter on the ground than they used to be.
I've heard it said before time and time again that toe is the only (OE) adjustment in the rear, but I need proof, especially since I've had such good results w/what I've done. The tires are wearing normally now. The car turns in much better and I can even induce a little oversteer w/throttle lift or trail braking if I want to.
Sorry SST, but I must challenge you on this one.

 

My information came from the Mazdaspeed engineers I was working with at the time. That's why I went with the camber links. I didn't do the alignment myself, so I'm not sure about the eccentric bolts you're speaking of. I didn't need to mess with any of the lower control arm fasteners to install the springs.

It's possible you got some camber adjustment out of it, but it may have adjusted something else as well. (caster, toe, or maybe even track width)...Not really sure to be honest with you. I just know when I discussed it with the engineer, he stated the only way to correct the rear camber and all suspension settings to within spec. after the drop was with the longer upper links.

I had a few alignments done both before and after the installation of the springs and before/after the camber links, so I'm positive that all of the settings were correct in my 3 back to stock.

 

sstlaure,
Did the Speed3's and Speed6's come with camber kits already due to the sportier set up on them?

 

Not sure,I would expect theymay have come with unique suspension components to compensate for the drop to make the alignment correct...Although the factory drop on the Speed3/6 was only around 0.5" (Prokit springs drop approx 1-1.2")