Hello and good evening.

I tried to install the swift springs on my 11 g37x sedan this long weekend.

I have 0 experience on DYI (except intake system) and this was first suspension work that I tried.

Due to 0 experience, I forgot to prepare the spring compressor. So I did all the way to taking off the stock coils (Took me 2 hours !!) but I was unable to take off the stock springs..

So I had to put everything back on

While I was putting everything back on, I was having hard time put the two-bolted black metal piece behind the rotor. I have the pictures below:

https://m.imgur.com/a/UmK88

Is this thing necessary to put back on? What is the purpose on these? It looks like it does nothing to hold or anything on performance wise..

Anyways, I was able to put it on the left side all the way and tightened it as it was before I took them off but I had really hard time put it back on the right side. So I just left them half screwed on left side.

I would appreciate it if you can explain what those pieces do, and if they are necessary for my vehicle.

 

That's a poser. I don't see it on the parts diagram.

It should appear just to the right of the digit "6".