Ohlins coilovers upgrade + what else needs replacing??

Hi all, I bought an Ohlins Road & Track coilover kit for my 996 C4S. My car has 160k miles and the suspension is harsh and crashy, plus a little bit pitchy. Kind of brutal. From reviews I read here and elsewhere, the Ohlins coilovers will make a big difference both in terms of handling and ride quality. But with 160k miles on my chassis, I'm sure there are other worn-out components. Control arms + links at all four corner, plus 3 extra links at each rear corner. Plus sway bar bushings and sway bar end links front and rear. From what I've read, the stock end links can work for the mild lowering (25mm?) of the Ohlins kit. But those are usually the cheapest and easiest parts to replace, so I figure those should be swapped for sure. My main question: should I go to the trouble of replacing the 5 links in the rear corners and the 2 links in the front corners? I have plenty of time (it's raining here in California) so I'm fine to send the links off and have the bushings swapped, if that's an option. Or is rebuilt + core swap the way to go? What special tools do I need to swap the shocks/springs? I know I have to get it aligned and corner-weighted. Looks like 9560 and 9546 are tools mentioned in the factory shop manual for the track rod ends. One is just a Torx tool. Also, the Ohlins instructions mention having to swap several cables for the Bose sound system. Seems crazy that the audio system would affect suspension. Can someone explain? PNs mentioned are 24631-01, 24632-01, 24633-01, 24633-02. Thank you in advance!

My car has 98K miles and the bushings are all shot, especially the ones in four rear upper control arms (dog bones), rear lower control arm, and the sway bar drop links front and rear. I looked into swapping out the bushings for polyurethane or the harder rubber ones from Elephant and it was way more than just buying new replacement arms from Pelican so that's how I went. For tools, I bought a ball joint separator like this Amazon Amazon

Just got done doing an �hlins R&T install. No special tools needed. I think the numbers you are referring to are the cable extension adjusters needed for the Bose system. The Bose box covers the adjusters so its impossible to adjust after putting the box back. As far as removing the Bose sub bax to do the install...this is very straight forward with no issues. My C4S has 100k but have not done the dog bones yet...swapped out all 4 top hats when I did the coilovers. After alignment all is very smooth...still working on getting the right dampening. Also added Terrett drop links to the fronts to eliminate any preload on the front swaybar. Could not dial out preload with the OEMs...rears were no problem.

It takes all of about 10 minutes to remove and replace the Bose sound box when you want to adjust the rear dampers. I just take it out after arriving at the track and then put it back in before leaving to go home.

Removing the Bose box is pretty easy. I screwed around a bit, so for everyone else: 1) fold down rear seats and pop off the Bose branded bezels. They come straight off. 2) 3 bolts are visible behind each bezel. Remove the bigger lower one. 3) Pull the entire Bose box forward. Flip forward and disconnect the connector. Don't try to remove both halves of the connector first. The connector that is joined to the box is solidly attached. Leave that one is place and split the two connectors. Then you can remove the entire box. 4) Pry around and work out the foam + carpet blocks to the outside of the metal brackets. You can see the 3 15mm bolts on each shock mount. It seems like you can force a 15mm socket in there and get the nuts started, but as you bring them upward it's harder and harder to work around the brackets. So I pulled up the bigger carpeted piece in between the brackets, then I could remove the brackets themselves by taking off 2 each 10mm nuts. Now it's easy to get to unload all three 15mm shock mount. OK, good deed done...I need help with the front end. I removed the left rear strut along with all 5 links. The bushings seem mostly healthy, but it was hard enough that I'm going to replace all of them. The only stressful part was when I fully backed off the lower control arm ball joint nut. The socket-end box wrench was jammed up under the ABS ring on the hub. I used an old-school pickle fork to pop the ball joint and it came down and then it was easy to get the wrench out. On the front end, it looks like I need to pull out the wheel hub and strut together. Not easy, but if I'm going to replace the control arms I'm not worried about trashing the ball joints. The only problem is that the car is now nicely in the air with the left rear corner suspension removed. So how to I remove the nut on the drive shaft in the wheel hub? I see two options: 1) have someone hold down the brake pedal while I go to town with an impact wrench. OR 2) put the wheel back on and drop the front of the car to the ground. 350Nm is a lot of torque to overcome. THANKS!

On further research, it looks like I might be able to pivot the strut out and remove the strut. Especially since I will be replacing the control arms, so I should get more articulation by removing those. BUT if I'm wrong, I'll have to put everything back together, and maybe even drop the front end with the wheels on, just to get enough resistance to remove the nut at the wheel carriers. THOUGHTS?

I am in Monterey as well. I have spring compressors and an electronic impact if you want to borrow them. I have a c2 and the suspension was very easy to switch out. Not sure if a c4s is any harder. Once you get in there it’s pretty simple.

On track cars I've done, (Not all Porsche.. just generally) If you go to a high end strut/coilover kit and don't upgrade all the joints to match,, it very quickly becomes a endless chase finding that last loose bushing/ball joint/bearing etc.. It seems like the better shock you run the more the deficiencies of everything else show up to party..

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As I�m planning to also upgrade to the Ohlins coilover kit in the near future, does this essentially mean replacing everything in the front (control arms, control arm links, tie rods, drop links, sway bar bushings) and rear (control arm links, drop links, and sway bar bushings) suspension at the same time?

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It really depends on the condition of your suspension. If you have multiple issues (noises, sloppy high speed handling, poor steering feel), then probably. If things are relatively tight, the Ohlins and maybe the Tarett drop links will be an amazing transformation. I would personally throw in Tarett front top mounts for steering feel, but that is up to you.

Kinda like the first time you go hard in to a turn on slicks after driving DOT track tires,, if you don't have the suspension up to the level of the tires it gets more exciting. <lol>

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It's easier to remove the drive shafts from the front diff rather than pulling the hubs off. this will allow you to pull the truth out without interference.

remove the drive shafts with the whole strut

I borrowed a huge Ingersoll Rand pneumatic impact wrench from work, and I happened to have a 32mm socket from a prior repair job. With my daughter pressing the brake pedal, it was easy to get the big driveshaft nut off. I could pull on the hub and the shaft would move in and out with the hub. It took some big wacks on the outer end of the shaft to un-seat it from inside the hub. Not sure what the benefit would be to take the axle off at the diff. Seems like that would only make the strut/hub/rotor assembly even more cumbersome to pull out. And accessing the bolts at the diff doesn't look too easy. In the end, either approach probably has it's pluses and minuses. I'm not planning track days with this car, but I'm a big fan of replacing items "while I'm in there" so I will replace all the control arms and links and dogbones with Meyle OE. New OE top mounts and bearings. New nuts everywhere but the bolts look fine. New sway bar bushings. I'm going to try to make (new) stock sway bar end links work. If not, those are easy to change later. Now my only question is the steering tie rods. I didn't damage the outer boots pulling them off the hubs. I'm inclined to leave them alone to make the job easier and keep the steering geometry close enough to drive to an alignment shop. (@mrdeezy got any shop suggestion?) Coming from BMWs, the steering feel of my car seems amazing to me. Like the end links, these are pretty easy to replace at a later date. OK one more question. What are the PNs for those 12mm nuts with the weird washers that hold the upper rear links to the wheel carrier? Can regular flanged 12mm bolts with 12mm washers work instead? Or skip washers all together?

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After I went and replaced my front top camber plates with Tarett monoballs I was informed that the OEM monoball mounts were of superior quality (at least on the GT3). I'm not taking the Tarett's out unless they fail, but the point is that Porsche OEM parts (particularly their motorsport) are not always inferior to aftermarket parts. I installed Ohlins R&T on my GT3 and find it an improvement over the Bilsteins, but they were also completely shot when I did. I still have some clunking going on, so I also agree with the point of cleaning house being a good idea.

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Fantastic looking GT3 BTW! Agreed on the GT3 version of the upper mount. The standard version is a fairly simple piece that is excellent for NVH (if new). The Tarett version is better IMHO (more camber adjustment, better steering feel). The switch transformed my 996.1 C2 for the better.

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Thank you. We bought it when it had 5,500 miles on it and it is now close to 140,00 miles with the original clutch and drive train. The car has been damn near bulletproof over the years. So far I've no complaints on the Tarett camber plates, except the bolts are not press-fit like the OEM plates. Tarett relies on Loctite to hold them in, which is probably more user-friendly for most of us (lacking a suitable press).

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don't unbolt the bolts at the center differential of the front axles. Just slide them out of the differential. Slip fit. No mess.

A quick Christmas update: My plan was to leave the old struts alone and sell them fully assembled along with all the links/arms I removed on ebay. But the Ohlins instructions at: https://www.ohlinsusa.com/files/ohli...MI_POZMN02.pdf are not so clear. I knew I would replace the top shock mounts along with the front shock bearings. Might as well replace the washers at that point. But the Ohlins instructions call for re-using the original "bearing with rubber isolator". The Porsche parts catalog don't mention a "rubber isolator". So I pulled apart a front strut and looked at all the parts. Clearly Ohlins wants me to re-use the bearing (996-343-501-00) plus the support ring (996-343-523-00) plus the spring plate (996-343-525-00). The spring plate is what they call the "rubber isolator" and is also called a "base" by Porsche. The washers are nearly new, as is the support ring. I'll re-use these but buy a new spring plate.

I reused the little tidbits onlins asked with no problem. As for shops in Monterey that is a super tough question. Classic coach works in Monterey looked at me like I was nuts when I’m asked them to do suspension work. I know mohr imports uses c and c in Sand city which seems to be the little Indy place to go. I originally came from San Diego so Clarance brown alignment was a specialized alignment shop, it was around 300 bucks... but they do race cars street cars everything. Monterey has little to nothing car wise. Good luck, I would go to San Jose or the Bay Area before going to a skuzzy tire shop for an alignment if it were me.

check this video out. Installs Ohlins. You Tube

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you mean that the drive shafts are not actually secured into the differential? I guess I could see how that might work. Since the outer end of the driveshaft is restricted from moving outward by all the suspension components it can't slide out enough to come free during driving. I guess the system needs some way to accommodate suspension movement. But what keeps everything sealed at the diff? As for removing the carrier from the outer end of the driveshaft, one downside is that the 22mm nuts costs $10 each and must be replaced.

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Good video thanks for sharing

I just bought a set of R&T's and the Tarett drop links for the front of my C2. The beginning of the winter project on the car. Think I'm going to try to get away with transferring the remaining parts off my stock stuff for the moment, if I need to go back and change that down the line its not too bad a job. At least that's my thinking at the moment.

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My wife and picked up her Sienna minivan this morning at Erickson Automotive and 4x4. Great shop. They do mostly Toyotas but also some race car projects, and I saw they have a new Hunter alignment rack. The owner Mike has a beastly 4 door muscle car that he autocrosses, which must be a heck of an alignment challenge. He's done GT3 alignments before. I'm going to give him a try. Will report back. $225 for a Porsche alignment, which sounds about right. Any suggestions for a semi-aggressive street / occasional HPDE alignment spec?

This is what I am using for my alignment which is working perfect for tire wear and HPDE performance. It is a little aggressive on Camber for a daily driver. I am at about 4000 total miles per year with around 12 track days per year. Front Camber -2.5~2.75 deg Caster max with camber above Total toe 0.08-0.12 deg OUT Rear Camber -2.4~2.6 deg Total toe 0.28-0.36 deg IN

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Correct. Easier than you might think. Slip fit into the diff, no seals or gaskets. Put something under the shaft so it doesn't fall when it comes out. Nothing fancy.