Suspension Rebuild- Suggestions Wanted

[PDKLOL]

Car has 133k on the chassis with mostly all original suspension. I'm planning to start with the rear first. I've got a set of Sway Away adjustable springs plates ordered. Planning to also replace the following:

• control arm bushings
• wheel bearings
• shocks

I'm thinking of going factory with the wheel bearings and bushings but wasn't sure if I should be replacing anything else while in there or what shocks to go with. I'm not looking to turn this into a track animal but also enjoy cornering pretty hard on the street and in the mountains. I will occasionally autocross this car as well. I should also mention that I plan to have the car slightly lower than euro spec height. I'm looking for some advice on what's best to do for my situation.


Pics from last weekend at Daytona
[/url]

[/url]

[/url]

[jjeffries]

PDKLOL, this is perhaps the Mother of all Excellent Suspension Threads:

http://forums.pelicanparts.com/porsche-911-technical-forum/726309-78-sc-elephant-racing-suspension-rebuild.html

I did it a bit differently to Craig, taking a somewhat less ambitious approach for my 82 SC coupe:
- my car came with Bilstein front inserts (in Boge housings) and green rear Bilstein shiocks; I kept those
- I retained my stock torsion bars
- I went with Rebel RSR front and rear bushing sets (machined alloy housings with plastic liner/surface)
- Modified my spring plates to allow easier adjustment (like Rebel's own offering or look up post by CGARR)
- Trailing arm bushings I'd already replaced using Elephant's parts.
- New balljoints and new factory sway bar bushes.
- I then corner-balanced and aligned it.

Is it any good? I think so, but someone with more experience might have their own take. I took my time, paid attention to the cosmetics (blasted and refinished my control arms, had hardware and spring plates re-plated in yellow zinc, etc). It was a satisfying project done over last winter.

Statement of the obvious: many ways to approach this task, lots of opinions out there. Craig's thread is IMO a fantastic place to start.

Best of luck to you, John.

[smadsen]

The ultimate "slippery slope" project.

Since you're there, I'd service the steering rack, which may never have been done. Then change out the rubber bellows. Install the proper bump steer spacers since the car appears lowered slightly from stock.

[salayc]

For your rear project, consider replacing drop links and sway bar bushings. Also replacing transmission and motor mounts.

[chrismorse]

As long as you are doing the rear wheel bearings, this might be a good time to do the parking brake shoes and springs.
One possibility for a handling upgrade is to go a bit bigger on the t bars. Many guys find that when the front torsion bar bushings wear/deform, the t bar gets scored on the a arm, leading to the need to replace the t bar, then the question is do I do both?, which leads to well, why not up size them just a bit. This was my experience and I went for a 21/27set of bars.

IIRC, the sway away plates come with poly bushings and some guys had problems fitting them/noise. I believe Elephant makes a replacement for them.

Since the rear brakes will be off for the bearings, this might be a good time to freshen them up too, discs, PMB calipers, stainless lines.
Others have mentioned the swaybar bushings and drop links - I like the Elephant adjustable links with the weather/dirt protective boots. If you drill one or two more holes in the rear bar arm, you now have an adjustable rear bar. The bars are tough, so you will need good bits, (Cobalt).

Back to the front, most guys that do the service on the rack report very dry, worn components.

In general, rubber seems to be the bushing material for street/non race car bushing material. Elephant has "sport hardness" bushings for the rear trailing arm and the strut top, others have higher durometer rated A Rm and spring plate bushings as well.

Many have mentioned that "digressive valving" gives a better ride from the shocks.

As long as you are in there -
Chris��

[3rd_gear_Ted]

The car height adjustable piece on the end of the front T-bar's gets dimensional wear and can cause T-bar rubbing in the front torque tube. Check it for wear while in there.

[dtwa]

I replaced the following on my 85 Carrera with OEM components at around 90K miles:

• Front A-arm bushings (using Elephant Racing bushing tools)
• Front sway bar bushings
• Turbo tie rods (you probably have these already)
• Rear sway bar bushings
• Rear drop links
• Engine mounts
• Transmission mounts

Also replaced the factory Boge strut inserts/shocks with Koni yellow adjustables.

Made it drive like new.

The main improvements came from the front sway bar bushings and engine/trans mounts.

--Dave

[PDKLOL]

Thanks everyone! I thought about trying to have everything here when starting this project but it sounds like I'll start with what I have and assess the rest as I go. I wasn't even considering looking at the engine and trans mounts until those were mentioned.

[Smoove1010]

In addition to the other recommendations - when you have that front suspension and steering rack dropped, it's the perfect time to replace those rubber fuel lines up near the gas tank.
I refreshed my suspension all around with the ER bushing kits. I'm very happy with the results except for an odd "scrubbing" noise in the rear on some big bumps, haven't been able to pinpoint the cause yet.
This is a great, fun, satisfying project and I give two thumb's up to Craig's 78 SC Suspension thread mentioned above. That was my primary reference and inspiration when I started getting deep into my suspension refresh.

Good luck and enjoy!
GK

[PDKLOL]

I guess the big question is...Does anyone have experience with the raised spindle strut option up front for lowered cars and if it's worth it should I decide to ride lightly lower than euro spec.

[aston@ultrasw.c]

Originally Posted by PDKLOL

I guess the big question is...Does anyone have experience with the raised spindle strut option up front for lowered cars and if it's worth it should I decide to ride lightly lower than euro spec.

The rule of thumb is that the lower A arms should run level or downhill from the pivot to the wheel.

This will maintain neg camber under hard braking.

If they become uphill then the camber goes positive!

The other (real) reason for raising the spindles is the possibility of machining in some neg camber before welding them back together.

[Cairo94507]

My only comment would be newer plastic or similar bushings are nice for tightening up the car but they also make the ride less compliant for daily driving and can squeak at times. I went with Elephant Racing rubber on all of my suspension parts.

[PDKLOL]

Thanks for the feedback thus far everyone! I just ordered all new rubber from Glenn at Pelican. Every part is going to be HD Rennline. List so far:

EZ adjust spring plates (sway away was back ordered like 3 weeks)
swing arm bushings
A-arm bushings
front strut mount bushings

I have wheel bearings coming locally and will also need to get all 4 shocks. I'm planning to stick with inserts for the fronts for now and stay away from the raised spindle idea. I think I should be fine sticking to that approach if I keep it near euro height.

[aoncurly]

I had Elephant Racing in Santa Clara completely replace all suspension rubber and I suggest you do the same:
Furnish and Install (all rubber "Restoration" bushings)
Control Arm Bushings
Front Sway Bar Bushings
Ball Joints
Camber Plate Bushings
Bilstein Strut Inserts
Replace Front Torsion Bars (mine were worn - yours might be ok)
Bump Steer Kit
Rear Spring Plate Bushings
Rear Trailing Arm Bushings
Rear Bilstein Shocks
Rear Sway Bar Bushings
Blast and Powder Coat Front Nerf Bar, Condenser Protection Grid, Front Control Arms, Tow Hooks, and Steering Protection Plate
Cad Plate Rear Spring Plates
Weld and Repair Crack at Rear Spring Plate
Corner Balance and Alignment
Set Ride Height to Euro

Replacing everything saves you from aligning each time you do piecemeal suspension replacements and the car drives like new and is less harsh.

Good luck.

[SteveDraz]

+1 on Elephant Racing. Just got to website, it's real easy to do a build.

[jac1976]

And the customer service is great.

[Kraftwerk]

PDKLOL (nice plate btw)
I went for a full rebuild at about the same mileage, 130k Everything was in surprisingly good condition and worked, it was just aged, even the factory-marked-line on was still on all fasteners, I guess the guy with a torque wrench also carried a paint brush and some orange paint?

Echoing all the good information above:
+1 on re-plating stuff, it's a good time to get every thing suspension related off your car and have it CAD plated. I only did a few things, but wish I had done more. Budget for time accordingly. I sent some stuff up to Shaun at Tru-6 in Cambridge, MA and he did a fine job with quick turnaround. Also at 131k, replace everything rubber, including motor-mounts and tranny-mounts, get it all done at once.