rear sway bar upgrades to 74-77 911, ball pin?

[Kemo]

is it possible to go with newer, 78' type droplinks in the rear for the sway bars? if so, what would need to be done to the trailing arm ball pin? is it threaded?

thanks!!

[TRE Cup]

The pins are cast into the arms, so no; they cannot be removed. We have seen, but we don't recommend, where people have cut the pin off, smoothed the surface so its flush with the cast arm, Drilled/tapped/threaded , then used a spherical rod end link to connect to the SC/Carrera sway bar. I question the strength of using that approach as the size of the bolt , passing thru the spherical bearing to the new threaded hole in the remaining pin root, might not be adequately strong enough.
I know that several suppliers of the aftermarket sway bars use 8 mm bolts on the spring plate side of fastening links so maybe the modified threaded pin approach is okay ??

Are you after a stock larger rear bar? You can get an early larger diameter bar from a 74 Carrera that measures 18 mm o.d. Part number is 911 333 701 01
Just use a 18 mm wrench to check the diameter when you are looking for one

[Kemo]

TRE Cup, thanks for the reply, your input is always appreciated. This is for a friend of mine...I have a 78' and it seems there are a ton more options for the sway bars but they all tie into threaded part. the 74-77s, with that pin seems a bit odd to me. I think shaving it down and maybe drilling and tapping might work. I wonder if a steel threaded sleeve could be inserted with some JB weld to create a solid threaded foundation to use the later drop links. definitely something to consider.

thanks again for reply

[PeteKz]

My '73 has the ball ends too. I have not yet had a problem with them, other than when the plastic cups that fit over them fell apart after 45 years. I put new ones in and they work well and are simple and easy to disconnect and reconnect. If you're not building a track car, strongly consider sticking with what you have.

Other option is to sell the arms you have and buy used ones from a later car.

[TRE Cup]

Epoxy (JB Weld)? Uh... NOPE!

We have seen people making spherical bearing drop links with mountings on the spring plates (Like a Weltmeister, Tarrett, Rebel Racing bar would. You could even drill a new pair of holes closer to the front curve of the say bar to stiffen it more. Just make sure you extend the length of the new drop links so it better matches the rear arm geometry thru the movement curve

[Tom '74 911]

Kemo,
I'm not sure what your end goal is regarding changing from the stock sway bar, but a good alternative to stock is the Tarett/Elephant Racing version. It forgoes the stock ball & cup link to the trailing arm and instead attaches to the spring plate via the camber or toe adjustment bolt (can't remember which one). I have these on my '74 911 and they work well. Just a thought...

https://www.elephantracing.com/porsche/911/swaybars-for-911/retro-rsr-swaybars/

Best,
Tom

[Mr. Merk]

Easy peasy

Tarett Engineering Adjustable Drop Link Set For use with all 911/912/930 with 1978-89 factory rear sway bar as they include parts to attach to the spring plate at the camber eccentric instead of messing with anything on the swing arm.

21mm was the factory upgrade in 1986 also available here from our host

You'll also need the inexpensive bushings, 477 411 313 M

[Kemo]

Originally Posted by TRE Cup

Epoxy (JB Weld)? Uh... NOPE!

so the drop link would attach to the spring plate as opposed to the aluminum trailing arm. i had never considered this. thanks again for the input.

[Kemo]

Merk, Tom,

thanks for the links..i have a much better idea of how all this would work. So we could just leave the ball pin alone and just use the aftermarket to tie into the trailing arm...as mentioned...sounds easy peasy

[safe]

Originally Posted by Kemo

sounds easy peasy

Yes, it is!

[Mr. Merk]

Originally Posted by Mr. Merk

You'll also need the inexpensive bushings, 477 411 313 M

Found them! Link attached

[chrismorse]

IIRC, the ball mount on the 74 trailing arm interferes with the Elephant Heim jointed, adjustable drop links. I cut off the ball and all was fine.
I went with Tarrett's 22mm hollow adjustable bars F & R, 21-27 Torsions and HD/sport rubber bushings, Elephant adjustable spring plates

Don't forget to check the condition of the chassis bar attachment brackets. When i inherited the car, one was missing, (along with the bar and links) Welded on the Wevo bar mounts - work well.

chris