MrNvgtr

Having just set the ball rolling by ordering a KW V3 suspension for my 1991 C4, and since I have like a year before it gets here from Europe, I'm trying to research the install process to figure out if I can do it myself or just take it to my local Porsche mechanic and lighten my wallet even more. I actually assisted with install of a Ground-Control coil-over suspension on my '99 M Coupe back in '04. I've also read a few basic DIY write-ups, which just has my head spinning regarding a few parts of the install. I don't really feel that I understand the job completely. Here are a few questions that I think would help me determine which way to go on this:

1. What items from my car that need to be re-used should I just go ahead and buy now? Looks like there are some rubber bits toward the top and some brake line tabs that will likely be worn out or will likely break during the install. I'm worried I read correctly that I will be replacing brake lines. Just buying this stuff ahead of time will help keep this from turning into a multi-week install while awaiting parts to arrive.

2. What special tools do I need? I'm concerned about that top bolt that my friend had to use an air tool on with my GC coil-over install. When loosening the stock top bolt and when tightening the new one on the new suspension, I don't think we did it right. Clamping around the pristine damper while applying torque via the air tool or wrench wasn't too good for it. Seemed like it worked out in the end as we clamped and scratched it at the very top, but I'm trying to figure out how to do this right since I have a second chance. I'm sure there's a special trick that I'm just not seeing yet.

3. Is there a really good DIY write-up out there for the 964, particularly addressing any C4-specific issues?

Just wish I had more mechanical skill and/or knew some knowledgeable people in my area.

ScottR

Tagging along as I'm pondering the same DIY or not to DIY question for my 1990 C4.

FeralComprehension

I'm in the same boat. Here's a good site to check out: http://www.964uk.com/html/main.htm

I'm doing:
1. Springs and dampers.
2. Strut mounts, at least at the front (V3 come w/ rear mounts).
3. Walrod front control arm bushings.
4. Ball joints
5. Tie rods
6. Front halfshaft renewal (rears done recently).
7. Wheel bearings, possibly.
8. Inspect rear control arm bushings/spring-plate bushings.

KaiB

Bearing installation must be done properly with a press - you've got a good handle on all of the rest.

go for it...

FeralComprehension

I have a press. I've owned 4 VWs, two Audis and now the P-car. That press has seen some use.

falcor

Order the gaskets for the front top mounts before you start, I didn't and it took me two weeks to get them. A 7 mm hex bit with a ½ inch socket attachment is usefull for loosning the top nut together with a cut down 22 mm socked welded to a square or round piece of tube. Spring compressors are essential, a good airgun sure helps too.

raoul

check your front A arm bushes, polybushes are a great upgrade if you haven't already.

GeorgeK

Side question: if one has lowering springs already (Eibachs, wish I knew the model, but not track oriented), is the spring compressor necessary, or are the sprins short enough that I can decompress them completely by loosening the adjusting rings on the threaded shock body?

jimq

I used my impact wrench to undo the top nut on the shocks with a rubber strap wrench to keep the shock from turning. Worked like a charm.
The hardest part of the whole thing for me was breaking loose the bottom bolts on the arm in the rear thats torqued 350 +/- lbs ! That took a 4 foot breaker bar and a lot of cussing.
If you have a 91 i hope you checked to make sure if you have the new or old style shocks on your car.

jimq

i tied the springs with a piece of rope so they couldnt spring out much. There isnt much pressure on them anyways. Just be sure to aim away from anything that could get hit if they let go fast.

FeralComprehension

Thanks for the tip; my copy of PET is down and I had no idea these were even in there....

freedman

Nor did I , but on checking

Gasket 964 341 511 80 x 2

christallon

It should take you 2 days of effort in the garage to get it done. I am glad I did this install myself as it brought me closer to the car. It's heavy work, so expect to feel it the next day. The DIY from that site is what I used. Pretty good instructions. I figure I saved $1,200-$1,500 in labor alone doing it myself. That made it easoier to pop for the V3's. Awesome suspension system BTW.

Best of luck

MrNvgtr

I like to be organized because I'm on a steep learning curve here, so I've re-organized the comments I've received thus far, with some clarification questions/comments added.

My original question was geared toward consumables that will likely be too worn to re-use. I was thinking more like stock replacements, then upgrades by exception. With question #1 re-stated, how would that change your suggested items?

These are great suggestions for questions #1 and #2. Can you please explain the 7 mm hex bit with 1/2 inch socket attachment? I'm having a hard time visualizing how you'd be using this.

See comment for FeralComprehension. I'm just trying to differentiate what I need (see original question #1) vs upgrades, which I didn't ask about. Just trying to keep this simple and within scope. Then I can go back and upgrade in the future.

Great answer for question #2. I've never heard of a rubber strap wrench though. I guess I'll have to look that up.

That write-up confuses me where it talks about the brake fluid connectors. Otherwse, it seems pretty well written if I don’t get caught up there. Can anyone explain what the issue is with that connection? The way I’m reading it, I actually have to separate the lines and have brake fluid spewing everywhere unless I clamp it down just right. Can anyone comment on that?

falcor

Here's my special tool, a cut down 22 mm socket with a handle welded onto it.

The 7 mm hex is used to hold on to the shockpiston while the special tool undoes/tightens the nut.