I measured the bottom mounting hole of the shock at 14mm. The bolt itself is a M14 x 1.5 and i've chased it with a die. I don't think i'll use it again. The AL arm has a steel sleeve pressed in. The threads on both arms look bad on the inside.
I can run a M14 x 1.5 Tap through it if its suppose to be it. Then if i can't get some decent threads in it, i'll have to go with a bigger bolt and tap the arm larger to probably a M16. Then machine the head off of it, turn it down to 14mm, toss a thread on it and nut the end. Another option is to do what Steve C mentioned above, drill it right through, machine a face on it so a nut will fall square on it.
Or get new arms.
Alex, do you know what it the thread on the inside on the arm? If its M14 x 1.25 or M14 x 1.75, that would explain the M14 x 1.5 bolt stripping it out.
The springs are marked,
Top black,
Eibach 41/99
ERS 140-60-120
Bottom Red
Eibach 27/98
ERS 40-60-55
How do we know the springrates?
alt+f4, noticed today the red bottom spring is softer as its the only one that moved when lifting the car to pull the other side apart. So what you are saying makes sense.:agree:
Pete