IcemanG17

bilsteins with stock springs is a VERY good combo for a street driven 928...better in the corners than the Boges, but not overly harsh.....even with larger 18" wheels

I have found street 928's with bilstein-eibachs overly bouncy on the street and just generally harsh....

But the cut eibach-bilsteins on my race 928 are GREAT...handles EXCELLENT....but I don't drive on the street either

I was impressed with the ride quality of an S4 with bilsteins and hypercoil 600F-400R..handles great on track and still has a nice ride...

mickster

To an earlier point, the shop checking it will know if the springs are good or not; and I think I'm going Bilstein/Stock as the New York roads will take their toll. I can always add the Eibachs later.

andy-gts

What about externally adjustable for compression and rebound.....then you could tune for street and then retune for competition, track or ORR. any one have any experience with penske, leda etc...I seem to remember TAHOE SHARK had penske I think

anyone know?

andy

Ragnar Joensen

As I know it was only the springs that were different with this option, red BOGE or Bilsteins versus grey BOGE without the option.

The option was standard on the GT and Club Sport cars.

The Club Sport had also stiffer springs in the front, 10% stiffer compared to the standard setup.

Give an idea how good the springs actually were for the 928 range.


Ragnar

Tom in Austin

I'm going Bilstein with standard springs. My car came with M474 Boge Reds, from what people have discussed here, guessing this will be about the same in ride and handling ...

mickster

I'm glad to hear what you said about the M474 Boge Reds being like Bilstein. Are you running 17" wheels?

Thanks you everyone who has replied so far! Great info!

blown 87

From looking at PET it looks like there are three different part numbers for the springs on my S4, does any body know what that means and how to tell which you have on your car?

IcemanG17

Tim does have double adjustable Penskes on the Beast...but they are PRICEY too....around the cost of the set of bilsteins per SHOCK....

Ispeed

Bilsteins and stock springs are a very good daily set-up. Most people would be pretty happy with that.

mickster

Coming out of Boston I know I can trust that recommendation!

6mil928

I did the Eibachs with new Boge shocks. The combo is not firm enough in my opinion.

Vilhuer

There are three different versions of same basic spring. Individual springs were measured and split into three groups based on their thightness. Measurement is done by compressing spring to certain spring type specific selected lenght and measuring how much force it creates.

On production line only same group springs were used at same axle. Those cars which got more options only used two stronger group springs to compensate for heavier options. Springs have one to three paint markings which tell which group they are. WSM has values for each group.

When replacing individual springs same group replacement should be used or if not available both need to be changed. Thats why PET has option of ordering all three possibilities.

M. Requin

My 86.5 is ok on smooth roads, but on even the slightest amount of washboard on a gravel road it's terrible, I lost my eye teeth thousands of miles ago! And the rattles, noises, stuff getting loose is just as you describe. I thought it was just the shocks going but now I'll have a good look at the springs, too.

Daniel Dudley

WHAT HE SAID. I have nothing against the Bilstein Eibach combo, but I think the SHocks are under damped for the springs, so they don't handle the real world conditions as well as properly matched springs and shocks.

I have heavy springs and Konis on the 85. It rides well considering, but it is no longer a GT in any way.

rdisney

Please correct me if I'm wrong. I believe Bilstein has regressive valving and Eibach has progressive.
A few questions about regressive/progressive for those that have driven both.
Can you feel the difference between the two types of valving on a bumpy road?
Can you feel the difference between the two types of valving on the track?
I'm guessing the regressive would be good for track because they start of harder and will help stay flat in corners. If a bump is encountered then it softens to absorb the bump

But at what point does the regressive soften? I'm sure it would for a pot hole at freeway speeds, but what about a speed bump in a parking lot driving 5MPH.

I'm also guessing, while track driving, the driver can’t turn the steering wheel fast enough to cause the regressive to go soft during cornering

Ron.