Use R32 GTR with two 3mm spring lock washers each side. And plenty of licktite. WOrked fine on the S14. The threads are the same throught the racks on the S body. But the S14 has really short rack ends on the rods, so you cant put spacers on them. Ive not seen S15 items out the rack, but if you use the GTR ones theyre the exact same part as the Tein ones (thicker) and have the longer thread.
Also, S15 tension rods, if you look at them, have a bend in them, exactly where you would expect a wheel to rub with extra lock....
Weird!

Its almost like they know you cant run the lower offsets you can on the S14 and so accomodate it in the arch more :wack: