74 911 sway bars

[74-911]

The drop link -> ball bushings on the rear sway bar are about gone. Getting ready to order all required rear sway bushings from PP so I measured the rear sway bar with calipers(cheap) and am getting 18.5 mm? The fronts are measuring 21.5mm. I assume I assume I need to order 19mm rear bushings? or perhaps get some better calipers?

Are these ( 19mm rear / 22mm front) standard factory sizes for a 74 911?

I have been searching the site for specifics on 74 factory sway bars but not really getting anything.

This is the first step in eventually replacing all suspension bushings.

Thanks in advance.
Jack

[Pat S]

My 74 has a 16 up front and none in the back

[Evans, Marv]

The '86 to '89s had 22mm for the fronts, '74 had 18mm rear. Your 21.5 coule be 22 and 18.5 could be 18, depending on your accuracy. Maybe a PO changed the sway bars.

[poorsha]

Porsche Tech Spec booklet states the following for the 911 and 911S:
Front @ 16mm
Rear @ NONE
Carrera:
Front @ 20mm
Rear @ 18mm
Having said that, my palin jane 911 (with all "S" options) has the following:
Front @ 20.5mm
Rear @ 18.5mm
Hope this helps a little.

[CHILI]

Originally posted by Pat S
My 74 has a 16 up front and none in the back

Same here, so I had the mounts welded on (with some customizing to make them stronger) and installed an 18mm in the rear. I don't understand why Porsche has thicker bars in the front when all of the weight is in the rear??? Now I have 16 front and 18 rear. Still pushes a little. but, maybe because I have 245's in the rear.

[Pat S]

Chili,
I am in the process of ording all the parts to do this also.
I'm going to try 21/27 torsions with 20front/18rear sways.
I'm also replacing all bushings and adding factory adjustable swaybars.

Did you weld on the factory mounts or another type? Also did you use factory drop links or custom ones?

I assumed the reason for stiffer front is to induce understeer to counteract the weight in the back.

Pat