Here is a picture of two front struts. The skinnier one has a rubber "bumper" the thicker one doesn't have one. Why the difference? different manufacturer? For different year 914?

Thanks,
Buck

The one with the large tube has a Bilstein insert. Check the part number on each strut. Cant tell from the view if they are early or late

+1

And as for why, cheap or dumb PO.

Did you have two different lower ball joints, one with a half moon for a bolt and another angled for the wedge bolt?

I ask that because the bottom one looks like an early through bolt style and the top looks like a late wedge bolt style. Can't really tell from the pic.

Your car took a hit at some point?

So there are the strut inserts....and then the strut housings.

So which are you referring to?

If you are referring to the strut inserts then yes...they will vary by manuf. You can spin off the strut retaining nuts with a pipe wrench.

If you are talking about the strut housings then there are also differing ones. The early 70-72 had a different ball joint and brakes while the late had a different ball joints.