Identifying 911 Struts, what are the pertinent factors Options

[McMark]

I'm sure the struts on the 911 was exactly the same for a long time. Various hubs bolted on the strut would give you various back spacings, etc. What I'm curious about is if someone had say, four 911 struts, what measurements are pertinent to decide what is compatible and what is not?

1. Caliper Bolt Spacing is an obvious first measurement.

Beyond that, are there different wheel bearing diameters? Different spindle lengths? What about determining which shocks will work and which wont?

[lapuwali]

I'm sure the struts on the 911 was exactly the same for a long time. Various hubs bolted on the strut would give you various back spacings, etc. What I'm curious about is if someone had say, four 911 struts, what measurements are pertinent to decide what is compatible and what is not?

1. Caliper Bolt Spacing is an obvious first measurement.

Beyond that, are there different wheel bearing diameters? Different spindle lengths? What about determining which shocks will work and which wont?

Caliper bolt spacing actually doesn't always work, as M struts have the same 3" spacing as 914 struts. Spindle diameter is different, however. I *think* the 911 spindles are larger in diameter than 914 spindles, but I don't know the actual figures.

Pre-69 911 struts are also very different from 69 and later, as the balljoint attaches in a completely different way (not just the pinch bolt v. wedge pin difference that appeared in 72-73).