Dimi 944

It seems you need new rear shocks based on the description of how your rear suspension behaves.

Also, for your application I would stay with good stock or aftermarket touring shocks and stock ride height. You would want to have suspension travel for the uneven roads you drive on.
I would not lighten the car either as this will compromise the ride. Think about the nice heavy sedans and they ride quality. They usually are over 3500# and have big wheels and wide tires which are not light. Their suspension geometry is different but there is nothing much and cheap you can do about it on the 944.

I have an S2 with oem Koni sport suspension and stock torsion bars with 17". It does have a surprisingly compliant ride with the pavement. The suspension is firmer than stock but the shocks are really good and do what they are supposed to.

V2Rocket

My rear shocks were installed in 2006 and might have 50,000 miles, probably less (broken odo).

I wouldn't say the ride is bad, on most road surfaces its very comfy and does take up the bumps very well. But its when the pavement gets awful that I want to try to improve it.

I know they are incomparable based on suspension designs but I can drive the same stretches of terrible roads in my 944 and in my lady's Impreza and the Suby is way quieter and comfier over those patches of rough pavement. Suby has 16 or 17" wheels, about the same wheelbase as the 944 (a little longer), but has a Mac strut rear suspension and fairly soft springs.

I don't know how they build roads in you guys' parts of the world but here because of heat and earthquakes the freeways are built in big concrete slabs the width of the road but maybe 15 feet wide. So every 15 feet or so you hit the bump/joint between slabs and there's a lot of bump-bump noise which is OK. But there is a big difference how the front/rear wheels handle the bump - the front wheels go over the bump and make no noise and no real bumping is FELT but when the rear wheels go over the bump you can hear the tires/suspension hit the bump and you get a small kick in the ***. Maybe its just a consequence of basically sitting on the rear suspension (my seat is all the way back) that can't be dealt with. I would just like to see about getting the rear to handle those bumps the same as the front does. At higher speeds (30+mph) you barely feel the transition between slabs but in traffic its annoying.

KYB shocks are garbage for ride quality. I've driven cars with them installed and wanted to get out ASAP even on decent roads.

Van

Wow, that's a lot. Even after 10k miles, new shocks feel much better than old ones.

Dimi 944

2nd

V2Rocket

Are you saying you swap out shocks after 10k miles?
The car rides well on most surfaces and doesn't undulate or jiggle very much during the "push down on the fender hard and watch it rebound" test so I figure they're still good.

Shocks should be 50-75,000 mile parts, should they not?
I just changed my front brakes a month or two ago with we'll say 48,000 miles since 2006, because they had just run out of material. Might do the rears on Sunday since I have the pads anyways. For non-tracked cars is that excessive?

Van

I'm not saying you *need* to change shocks after 10k miles, or even that I do... I'm merely stating that shocks with 10k miles will not perform as well as new shocks - enough so that you can feel a difference.

Shocks are an item that has a half life. I don't know the exact numbers, but I expect that in 20 thousand miles, they are 50% as good as new. At 40k miles, they are 25% as good as new. At 60k miles they are 12.5% as good as new. And so on.

The problem is, people tend to run them until they get some kind of mechanical failure.... But really, the shock has long since stopped being an effective damper.

Simply put, if you're considering changing brake calipers to change the the unsprung weight by ounces, that's splitting hairs compared to the lion's share of the performance benefit that you could get from changing medium-quality shocks every year!

Dave W.

Have you checked the rear suspension bushings? If they've gone bad it might allow too much freeplay in the pivots, which will send a second jolt through the car after you hit a bump and the trailing arm bounces back to it's resting position. The easy way to test for loose pivots is to push on the side of the rear wheel and see if it moves.

I'd also recommend a pair of rear Koni sport shocks, just put them on the softest setting. You'll benefit from the advanced damper design.

VirginiaF1

Great advice, thanks.
As is Van's half-life quote on shock life..

As with Rocket, I'm gearing up for rear susp replacements.
Went with Sachs front shocks and KYB (pls don't laugh) in rear.
The Sachs are still great after 12k but the KYB's are now booming over my same crappy Richmond roads.

Original rear bushings (all front bushings replaced last year) and orig torsion bars.
So yeah, rear shocks and bushings on the horizon.

My Question:
Do our Torsion bars actually require Replacement after 230k miles like Rocket's or my 282k?
Or merely replace the shocks & bushings?
Thx!

V2Rocket

Hey now, my car isn't much over 100k miles
Don't call a lady older than she might be.

H.F.B.

Apart from the 951 caliper, the Rennbay "Porsche 944 NA Big Brake Kit - Wilwood" would save some weight too.
Stock brakes vs Wilwood brakes = 14 lbs over all weight savings

MAGK944

Are the Willwoods really that light, only 3 lbs a piece?

H.F.B.

That information is according to their website and they describe it as 4 Piston Aluminum Caliper. So why not? You probably shouldn't drive the calipers in winter in Sweden or Canada because of the road salt.

MAGK944

I'll have to check but I cannot imagine they are only 3 lbs, that's 4 lbs lighter than 951 4-pot aluminum calipers, less than half the weight!

H.F.B.

ok, that's good. Let us know.

H.F.B.

I've just noticed, this was already discussed.
https://rennlist.com/forums/924-931-...-944-na-3.html