Basic Suspension Question

Would swapping B4 Bilsteins for the existing shocks on my 987.1 (Base) Cayman give me a more compliant ride? My car has 51K kms and, being the second owner, I assume that the shocks are original. I am experiencing a very harsh ride at the rear, which I need to resolve. Reducing tire pressure to 32 lbs has a negligible effect on the problem. I understand "firm, sporty" ride, but I don't think a sports car needs to crash over (for e.g.) rumble strips, to the point that one's passion for the car takes a serious hit. Proper, refined sports cars can absorb such road problems while still giving one good cornering characteristics (see Chris Harris's video discussion with Gordon Murray on the subject). The problem I have in the Cayman is akin to what I experienced in my BMW M-sport 135i. That car too had a harsh ride, while the non-sport suspension was supple. I have no interest in tracking my car, nor do I wish to lower it. So, I'm wondering if B4 Bilsteins might be valved differently from stock, thereby reducing or eliminating the problem. (From my hours of research on this subject, it seems there is no consensus whether B4's are actually OEM shocks or whether Bilsteins simply lists them as OEM replacement.)

I think you should first find out if you are in fact on original shocks, the previous owner may have swapped in a firmer set for handling.

I would agree, though I doubt that he did this, given the fact that the car came with BF Goodrich G-force Comp 2 All Seasons. Still, he might have had a set of track tires that I'm not aware of. The shocks appear to be generic black OEM items. I'll take a closer look to see if I can see a part number printed on them.

what size are your tires? If you want a softer ride downgrading to a 17" wheel with bigger sidewall might help.

I have the 18" wheels. 17" wheels would help, though I still think the shocks are problematic, given how little difference it has made to reduce the tire pressure.

When you say “crash” are you talking about a feeling or a sound? It could be that your upper strut mounts are toast or it could be that the counter weight in your hatch is loose and is crashing around on hard impacts. Sent from my iPhone using Tapatalk

Jacked up the car (right side) and checked the shocks. To my eye, they look OEM:

So, back to my original question: Does anyone know whether the B4 Bilsteins are more compliant (particularly with initial shock travel, caused by small, sharp road imperfections) than the OEM shocks? (I'm talking about the rear shocks; the fronts cause no problems with ride harshness.) Also, is there a way to test/check the top strut mounts without disassembling the suspension? TIA ...

from what i've read I believe the b4 and oem shocks are the same, If you feel the fronts are fine maybe its just a problem with the back shocks, such as the shock going bad or the strut mounts?

I have PASM and I find the ride better in sport mode ( Boxster ). 19" tires. What is the date code on your tires? All-seasons are really no-seasons on a Porsche . If the tires are old they will not flex properly. If they are older than 6 years they are toast.

Like Xsbank, I am also thinking about your tires. When I bought my car the tires on it were 7 years old and hard as rocks. Replacing them with new rubber did wonders for the ride quality.

That too is a factor that I'm aware of/concerned about. The dates are 2012/2014, and yes, all-seasons are a compromise. But I can't justify running summer tires on the car, particularly when our high-altitude climate can bring on snow just about any month of the year. I've been researching/comparing the Continental ExtremeContact DWS06 vs Michelin PS All-season 4 tires. I always prefer Michelins, and the A/S+3's on my BMW were more than good enough for me. But the kicker here is that the Continentals have a more comfortable ride than the Michelins, which, given my suspension woe, makes me think the Continentals are the way to go. But do I want to sacrifice steering response, which is a characteristic of the Contis? Not really. So, back to the B4 Bilstein /shock question ... (Besides, I find it odd that one has to use to tires to resolve a suspension problem. Seems like the suspension should be a first-order fix.) Argh ... most frustrating, this issue. Twice now (first time, the M-Sport 135i) have purchased a car from a company that has a reputation for building fine sports/road cars. Each time, I've been surprised and disappointed. (Btw, I drove a non-M-Sport e90 a couple of weeks ago and was amazed at the refinement of the ride. Not in terms of comfort, but in terms of quality of bump absorption and cornering on regular imperfect city roads. It was an eye-opener really, and has me questioning whether to keep the Cayman . A bugger decision, given that I've always wanted a Porsche ...)

What tires did you buy as replacements? Also, what were the tires that you replaced?

The old tires I replaced were Goodyear Eagle F-1s. I replaced them with Hankook Ventus, which were decent. That was 6 years ago. I wore those out and this time went with Michelin PS4S , which are outstanding both in ride quality and handling. I live in SoCal so weather/temperature are not an issue. Sounds like all season tires make more sense for your location. I have heard many good things about the Conti DSWs - we have them on my wife's car and they are comfortable and very long-lasting. I don't have any experience with them on a sports car, though.

Having compared Bilstein B4 PASM to OEM PASM shocks, the B4 shocks are effectively the same to the user—if not actually identical. I haven't compared the non-PASM shocks, so conceivably those might not be the same... but that'd be strange. I'm running OEM PASM, and I don't have a harsh rear... My next suggestion was to see if they had seized/been damaged/etc, but your pictures suggest your shocks are in pretty good nick—I'd be doubtful there's anything actually wrong. Sorry I couldn't provide any other suggestions!

I've just ordered a set of Conti DSW06's. I hope they work for me, both in terms of reduced harshness and decent steering feel.

Not a problem. I appreciate your input and experience. As I stated to another poster, I've ordered a new set of tires and will see where that takes me.

I can understand the frustration on getting info on the Bilsteins as the marketing materials previously didn't really compare vs. OEM or original parts. The B4 is supposed to be equivalent to stock or within 10% of OEM specs (I forgot where I read this). I had a similar issue when first transitioning to my car - the ride on 19's even with Michelins were a bit busy for the roads I frequent. Changing to B4 improved the "crashiness" over bumps and improved the "feel" but didn't really improve the comfort. This was likely due to the age of the absorbers. Usually absorbers only last 50k-100k kms where I am and if your roads are similar, it may be worth considering a swap simply for this reason. tyre pressures make a really small difference but you could try going up 2 psi instead of down and see if it makes a difference. the reality is that these cars, running 18-20 inch wheels are going to feel a little bumpy/busy. the most effective solution probably is to switch to 17' wheels or to get a 981 / 718 which is less raw. Me? I decided to swap to B6's for the sportier handling and grin and bear for the rough roads. I now have a regular visit to the chiro for a tune up too

I replaced my BMW M-sport suspension with (among other things) B8's, and loved them. Should have kept that car ... I'm committed now to changing out the near-worn-out B.F. Goodrichs for Continentals. Will post my experience once they are installed--should happen next week sometime.

To bring this thread to a close, I did have the Continental DWS06's installed, and they absolutely changed how the car performed. The ride is still very firm (even hard), but I don't grit my teeth when heading towards a texas gate. I'm sure the Michelin alternative would have been even better, but they're not available right now in my area.

glad to your hear you solved your ride problem! Looks like the age of your tires caused them to get too hard causing the harsh ride.