13bt rienforced rear iron
 

So after learning about s5 rear iron differences, I had to check my garage. I only have this one rear iron, so I have nothing to compare it to except the picture from this website, Rotary Resurrection home of the budget rebuild.

So mine looks like it, but was hoping you guys out there with multiple engine parts would be able to tell me. It measures around 1/2" thick. No way to measure to see if it has been resurfaced huh?
Attachment 645727

that is the bigger one, see the extra rib?

you can kind of tell if the irons been surfaced, measure the thickness, its supposed to be an even number like 60mm

So I have a total of 3 rear irons with the reinforcement and now I know the difference between the thicker casting vs the smaller one. Besides the photos from rotary resurrection, I have pictures of an assembled engine with thicker vs thinner dowel casting.

Here is the thinner casting. it has the extra support, but the casting thickness is almost flush with the rotor housing
Attachment 645147

Here is the thicker casting version of the rear iron. It pops out about 6-8mm past the rotor housing
Attachment 645148