'84 Carrera Suspension Rebuild

[Golfin_Fool]

I am looking to rebuild front and rear suspension on my Targa. Any suggestions on the parts lists? I am not tracking the car, but it is a daily driver and I'd like to get the wifey a little more interested in being in it...she says it rides like an old car!

Thanks all!

[Driven97]

Here's a couple of threads worth reading:

'78 SC Elephant Racing Suspension Rebuild

ROW SC - Turning my attention to suspension

You can do anything from just throwing on some fresh shocks, to tearing the whole car apart, and everywhere in between. All depends on how much you like shoveling money around.

And of course it rides like an old car. It's an old car. No matter what you do it's not going to ride like that LX570.

[darrin]

what specifically causes your wife to feel your 911 rides like an "old car" -- I've been very surprised by how LITTLE work my '86 targa's suspension has needed -- switching out my original boge shocks for new koni adjustable (and a GOOD alignment) made a huge difference - you might want to start with shocks and an alignment as first steps. While I've upgraded to turbo tie rods (had to replace a tie rod that broke during a repair), I've not found this upgrade to make much difference.

Who do you take your 911 to for work in the denver area?

[RSTarga]

Originally Posted by Golfin_Fool

I am looking to rebuild front and rear suspension on my Targa. Any suggestions on the parts lists? I am not tracking the car, but it is a daily driver and I'd like to get the wifey a little more interested in being in it...she says it rides like an old car!

Thanks all!

Time to get a young girlfriend

[GH85Carrera]

Suspension work can be a very slippery slope. If you have no intention of tracking it and you want a real street car daily driver things are a LOT cheaper. To do it right you likely will want to replace (read that NEED to replace) all the rubber bushings with new rubber bushings. Replace the ball joints and shocks. 85% to 90% chance the torsion bars are shot if the bushings are original. If there are any wear marks on the t-bars, just replace them. The factory size bars are pretty hard to find. I went to 21mm front and 27 rear and I drive my car on long road trips with my wife. We drove 5.500 miles last summer on a two week trip.

I went with Bilstien HD shocks not the sport shocks. I did upgrade to turbo tie rods mostly because they are a much better design. I had the a-arms powder coated.

I think the final results are spectacular. It still rides comfortably and handles great.

You will find a thousand different opinions on the board.

[stlrj]

I seriously doubt rebuilding your suspension would make your 911 more comfortable but replacing your tires with a higher profile all season type would.

Cheers,

Joe

[kyngfish]

Just a suggestion, you may have already done this, but go through and replace rubber bushings, tie rods, anything that might seem old, it will feel tighter. Once you have all the little stuff sorted, replace your inserts.

[Golfin_Fool]

Originally Posted by Driven97

And of course it rides like an old car. It's an old car. No matter what you do it's not going to ride like that LX570.

Thanks Matt. Now I have some good things to read for decisions. I like the "old car" ride, but updating suspension can't hurt and can help other parts last longer.

[Golfin_Fool]

Originally Posted by darrin

what specifically causes your wife to feel your 911 rides like an "old car" -- I've been very surprised by how LITTLE work my '86 targa's suspension has needed -- switching out my original boge shocks for new koni adjustable (and a GOOD alignment) made a huge difference - you might want to start with shocks and an alignment as first steps. While I've upgraded to turbo tie rods (had to replace a tie rod that broke during a repair), I've not found this upgrade to make much difference.

Who do you take your 911 to for work in the denver area?

I think the fact that you "feel" the road is what gets her. I try to get her to understand that there is a method to that madness. I like the idea of switching out the shocks and alignment. I may look to replace the bushings as well.

As for where I take my 911 for work...I haven't needed to yet. I've had it for just over two years and have only needed to change the oil. I do take it to Aspen Auto Clinic on Arapahoe for check ups, but they are not a Storz. I live in SE Aurora, so all the best shops are quite a drive away. May bite the bullet and start taking it to Storz.

[darrin]

I've been a long-time customer at Eisenbud's, but have heard nothing but great things about Storz as well. Seems the best next step would be to have somebody (at Storz/Eisenbud's/etc.) that's very familiar with how your car should ride/handle when properly set-up, drive your car and see "what's up" (if anything). As others have said on this thread, tire choice and wheel size play important roles in this too -- I personally like the ride/handling balance that my 16" continental extremecontact DW tires provide, but others find them to be soft and unresponsive. Ultimately, however, i find the road "feel" to be a key attribute of my targa and don't know if if'd like it if reduced to lexis-like levels.

[sugarwood]

I never did find out why people replace shocks when they aren't leaking.
The shock is a very simple fluid filled device.
Why would you replace it unless you want to change the dampening specs (revalving)
Does the oil inside the shock become thinner over time?

What does re-valving shocks accomplish? When is it needed?
Need help diagnosing what to refresh on suspension...

[Lake Guy]

I also had the same focus - not a track car and it needs to be comfortable enough for my wife to enjoy too. I replaced all the bushings and shocks with stock comprable parts and added turbo tie rods when I rebuilt the front end. Feels better but it's still a low slung 30+ year old sports car. It will never ride like our X5 or SQ5 (or my F150 even!) but it's a total hoot to have fun in. I also got seat heaters installed when the seats got reupholstered (because she gets cold with the top off). Everyone has a different focus for their 911 but for us it's about experiencing the targa together. Based on what the OP wrote I'd go with stock parts.

[Driven97]

Originally Posted by sugarwood

I never did find out why people replace shocks when they aren't leaking.
The shock is a very simple fluid filled device.
Why would you replace it unless you want to change the dampening specs (revalving)
Does the oil inside the shock become thinner over time?

A shock absorber isn't quite that simple. As the shock shaft enters the body, it takes up volume. Since shock fluid is incompressible, there has to be a way to take up that volume. Shocks are therefore gas charged (with nitrogen) in one of a few ways depending on how the shock is built:



Over time and many cycles, the nitrogen gas eventually works its way into the shock oil. Under the heat and pressure, these nitrogen bubbles cause cavitation and uneven flow through the piston, which equates to poor damping action. Also contaminates work their way into the oil slowly from the shaft side over many hundreds of thousands of cycles with the same negative effect.

In addition, many shock piston designs have plastic plates that deflect based on forces. As with any moving piece, they fatigue over time and fail to work as initially designed, again decreasing performance.

So shocks start dying a slow death the moment you bolt them on your car. While spectacular failures do occur, the slow degradation is tougher for most people to spot. For street use, every 50k or so they should be replaced for best performance. Note that even club racers will have their shocks rebuilt once a season at minimum, serious efforts after every event.

Also a pet peeve: "Damping" is a decrease in oscillation amplitude. "Dampening" is making something wet.

[stlrj]

Originally Posted by Golfin_Fool

Thanks Matt. Now I have some good things to read for decisions. I like the "old car" ride, but updating suspension can't hurt and can help other parts last longer.

Lots of hurt for your pocket book for very little if any noticeable benefit. For my money, I would invest in some decent tires and enjoy it.


Cheers,

Joe

[sugarwood]

What are the plastic plates inside the shock that fatigue?

[Monza_dh]

My recommendation is to do it all and do it right, once....I guess like anything else on these cars you can certainly over do it as well. If its a driver, replace front and rear bushings, drop links, rear shocks, front inserts, and add TTR's while your in there. It will transform your car.
Here's my thread from a few years ago:

Another suspension refresh powered by Pelican!

[A horse with no name]

Originally Posted by Monza_dh

My recommendation is to do it all and do it right, once....I guess like anything else on these cars you can certainly over do it as well. If its a driver, replace front and rear bushings, drop links, rear shocks, front inserts, and add TTR's while your in there. It will transform your car.
Here's my thread from a few years ago:

Another suspension refresh powered by Pelican!

+1...I just love your detail!- A job truely well done.

[Driven97]

Originally Posted by sugarwood

What are the plastic plates inside the shock that fatigue?

Here's a diagram of a Bilstein digressive shim stack. At low shaft speeds the plates are "closed" restricting flow to give good body control. At higher shaft speeds the plates flex out out of the way allowing more oil flow which softens the shock for comfort over bumps. Pretty neat stuff.

[sugarwood]

and you're saying the plastic starts to flex more over time? I supposed it could even break and you may not know, except that there is no damping anymore.

[Driven97]

¯\_(ツ)_/¯ not sure I don't rebuild shocks, nor have I ever inspected shock shims.

I guess my main point is you can have a completely dead one without any visible leaks.

My secondary point is that they die slowly, not all at once, which is very hard for most drivers to perceive. They're a regular wear item.