JWERION

I am wondering if the aluminum trailing arms from the mid 70's 911's are different from the SC trailing arms due to the wider rear track of the SC's. Thanks

Peter Zimmermann

I think they're the same. The easiest way to confirm is to call your dealer parts department and ask for the part number for a '74 trailing arm and the number for an '83 trailing arm. If the number's the same, so's the part... FYI: I'm not a wheel guru and have never compiled offset specs, etc., but factory info shows that such a small difference exists in the track between 2.7 liter cars and SCs that the difference could easily be made up in the wheel. As an example, a 7x16" alloy moves the track about 1" out (wider) than a 6x16" alloy. Half of that difference is half the increase in width, and half comes from a different offset. I hope this clarifies your question...
Pete

911pcars

The geometry of all the aluminum trailing arms is the same. The only difference is the sway bar drop link attachment on the arm. The early al. arms (74-77) use the ball attachment, same as early steel trailing arms. After '77 (or thereabouts), they used a threaded hole. Thus, probably different part numbers.

Hope this helps,
Sherwood
http://members.rennlist.org/911pcars

Morty

Does anyone know of an upgrade of the trailing arms that would be cost efficient? I am asking because I have heard (and not had confirmed from other sources) that installing the trailing arms from the turbo-models of the same era would be a great improvement for NA SCs and Carreras.

Peter Zimmermann

Sherwood: Thanks! I was struggling with the difference (sway bar mount), which, of course, would produce a different number, even with the same shape. You hit it right on the money...
Pete

JWERION

Thank you sherwood & Pete that clears things up perfectly.