Shock Advice

[jackportia]

'86 Carrera with Boges all around with approx 60k. Working well and if it aint broke...
but considering replacing the Boges with Bilstein HD's (stock torsion bars). Anyone with seat of the pants experience with the Boge/Bilstein swap? I'm wondering what I gain with Bilsteins and whether I should just change the oil, plump the tires and step off the slope? I also considered just changing the rears to Bilsteins and leaving the Boge fronts
alone.

[Farreem]

I recently made this exact change on my 86. I don't track or have any desire to track my car and I have to say its pretty firm. On a smooth road its great but when the road get's choppy you really feel it. Honestly, if i could go back I would have kept the original Boges. Just my feedback - hope it helps.

[jackportia]

Thanks Farreem, much appreciated.

[dreichman]

Any thoughts on the yellow adjustable Koni Sport Shocks?

[Driven97]

Koni yellows are pretty aggressive on rebound, even on the softer settings. Good for body control and performance, not great for ride. YMMV.

[Uwon]

I have had the same adjustable Konis which I transferred from my ‘86 to my current build. Total of 15 years on road, tracked 10 years, probably 200k miles (daily driver for part of time, been to mid-west, Deep South, and even drove to and did the Targa Newfoundland). Found the correct setting for both road and track early on and never looked back. About as comfortable as you can get in a 40 year old car.
Cheers,
Johan

[AG81]

I refreshed my tired Boges this year(88 coupe) and it really woke the car up. I didn't realize how bad my original equipment was. With my aggressive tires I am very happy I did not go with the Bilsteins. The ride quality is good not great and I fear the Bilsteins would have only aggravated my situation. I lightened the car quite a bit and this may be why my new Boges seem stiff. I drove the car a month and then readjusted the ride height.

[darrin]

Originally Posted by Uwon

I have had the same adjustable Konis which I transferred from my ‘86 to my current build. Total of 15 years on road, tracked 10 years, probably 200k miles (daily driver for part of time, been to mid-west, Deep South, and even drove to and did the Targa Newfoundland). Found the correct setting for both road and track early on and never looked back. About as comfortable as you can get in a 40 year old car.
Cheers,
Johan

started with boge, replaced with (used factory) bilsten and (when I bent a strut) ended up with adjustable konis on my '86 targa daily driver -- still VERY happy with these from both a handling AND ride quality perspective

[jackportia]

Thanks to all for taking the time to respond. Hadn't considered adjustable Koni.

[PFNog]

I just upgraded the Boge’s on my ’87 cab to Bilstein HD’s about a month ago – kept stock torsion bars. I also did a complete suspension bushing refresh with Elephant Racing rubber items. I was worried about added stiffness since it’s a cab, but the results were great! It lost the jarring feel it had before and the rear end used to feel like it wallowed a bit on fast corners. Now it feels planted, corners flat (for a road car) and bumps are met with a solid ‘thunk’ rather than a jarring impact. I strongly recommend the combo of Bilstein HD’s, standard T-bars, and fresh bushings for a very nice street ride (not track) that handles like a 911 should.

[PFNog]

I should also mention - I got it aligned and corner balanced after the suspension work. May as well do it right.

[jackportia]

Thanks PFNog. My 60k Boges are not giving me any grief, but thought Bilsteins might make a nice upgrade. Having no way to compare I posted for feedback, and that feedback has been both helpful and interesting. I know I'm overthinking this (overactive reticular formation), but was just looking for a little clarity as to whether the Bilsteins would provide enough positive handling (street driven) to make the switch worthwhile. Were your Boges high mileage prior to switch to Bilsteins?

[davidpsalt]

Like PFNog - I reworked my entire suspension last winter. Overhauled everything and went with Bilstien HD's up front and the rear. With just over 100k miles on her, I was getting tired of the squeeking rubber A Arm bushings when going over speed bumps in parking lots. Reworked the entire front end - A Arm bushings, kept stock torsion bars, new ball joints, sway bar bushes, Turbo Tie Rod kit, Bilstein HD cartridges and rebuilt my calipers, new brake hoses, new rotors and pads.

For the rear, I rebuilt both axles, replaced the swing plate bushes, original torsion bars, sway bar bushes, new end links, and Bilstein HD shocks. Very rewarding winter project in my garage - saved a ton of $$$ doing it all myself.

Corner balanced and alignment at my mechanics shop - can't believe how great it drives, handles etc Wish I had done this 3 years ago when I purchased the car. Oh, also a Cabriolet. Love it!

[GH85Carrera]

I did my suspension refresh in 2010. The Boge shocks were replaced with the Bilstien HD shocks, and T-bars replaced with 21 front and 27 rear, all rubber parts replaced with Elephant racing rubber. And of the typical Turbo tie rods and new ball joints, and rebuild the steering rack.

The car is still very comfortable on long road trips, and my wife is happy to ride along on long road trips. I have put over 40,000 miles on it since then. It steers like it is laser perfect, and can read my mind.

I did do a full alignment and corner balance after the suspension work. Oh, and it is at stock European ride height. Any lower makes it too hard to get up and down my driveway or parking lots with any ramp at all.

In my mind, it is the perfect setup for a street car and occasional autocross car.

[PFNog]

Jackportia - I don't know the exact mileage of the Boges that were on my car. It's a higher mileage car, and there was no documentation of a shock replacement... but when I pulled out the Boges, they didn't look all that old - especially the rears that are exposed to the elements, still looked pretty good. I know that is a poor way to tell how old they were, but I'd guess they'd been replaced at some point, no way to know how long ago. Sorry I can't be more helpful on that aspect of things.
I will say this - I replaced them because the car didn't handle as well as I thought it should. After the HD's and the suspension work - Wow!

[Driven97]

You can kinda / sorta check shocks off the car. Put it shaft side down on a piece of cardborad or something to protect the threads, and push. It should be relatively difficult to compress. More importantly, after you compress it, it should extend back out to full length by itself. If not, the gas charge is a goner. The shaft of a shock takes up space as it goes into a shock body, so there is pressurized gas somewhere in the shock (depending on design.) The pressure helps keep the shock fluid from cavitating as it flows through the piston, helping it work better.

If you've got a leaker, either fluid through the shaft seal or just the gas itself through somewhere, the pressure goes away and it no longer pushes the shaft back out.

It's not foolproof, but it's a free check that can give you some idea if your shocks are healthy or not.

[kevbo]

Great information, i'm going with the adjustable Koni's on my '86 Targa ordered from our host:

Koni Sport Shock, Rear Note: Externally adjustable without removal from car. Front: for original Bo
Part #: KON-8210-1159SPORT
Koni Sport Shock, Front (for original Boge struts only) Note: 911 G-Series Carrera/Turbo Externally
Part #: KON-8641-1039SPORT

[chrismorse]

Originally Posted by GH85Carrera

I did my suspension refresh in 2010. The Boge shocks were replaced with the Bilstien HD shocks, and T-bars replaced with 21 front and 27 rear, all rubber parts replaced with Elephant racing rubber. And of the typical Turbo tie rods and new ball joints, and rebuild the steering rack.

The car is still very comfortable on long road trips, and my wife is happy to ride along on long road trips. I have put over 40,000 miles on it since then. It steers like it is laser perfect, and can read my mind.

I did do a full alignment and corner balance after the suspension work. Oh, and it is at stock European ride height. Any lower makes it too hard to get up and down my driveway or parking lots with any ramp at all.

In my mind, it is the perfect setup for a street car and occasional autocross car.

Same, elephant rubber, 21/27 new bars, 20/18 sways, HD's, PMB calipers, new discs, air to center of discs, bearings, QuIfe quick rack, 915 is out for refresh/upgrade. Will corner weight at euro height. Bone stock 2.7 with M&K sport.
Be careful of slippery slope my 74 has been off the road for 6 years.
Regards,
chris

[RWebb]

Bilstein and tell them to digressively valve them with info on your car

[Cherry Bomb]

Originally Posted by GH85Carrera

I did my suspension refresh in 2010. The Boge shocks were replaced with the Bilstien HD shocks, and T-bars replaced with 21 front and 27 rear, all rubber parts replaced with Elephant racing rubber. And of the typical Turbo tie rods and new ball joints, and rebuild the steering rack.

The car is still very comfortable on long road trips, and my wife is happy to ride along on long road trips. I have put over 40,000 miles on it since then. It steers like it is laser perfect, and can read my mind.

I did do a full alignment and corner balance after the suspension work. Oh, and it is at stock European ride height. Any lower makes it too hard to get up and down my driveway or parking lots with any ramp at all.

In my mind, it is the perfect setup for a street car and occasional autocross car.

Nearly identical refresh list as my 83SCab. I added 87 Carrera sways, raised spindles with hollow bars from Chuck. It has performed as planned, perfect spirited driver...for hours....on all roads. Next I'll swap in adjustable raised spindle KW's and adjustable Eibach 25/24 sways for a bit more tuning as I go.