Suspension suspense

61porsche

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The answer is something we already have access to in the form of the specifications for CSLs. Just compare those to what you have and your desired state.

1. Travel was limited from standard, meaning less in the spring, shock absorbers/ struts. Think all four wheels off the ground ala Hans.

2. Springs were progressive wound type. As the spring compresses, more force is required. These were available over the years from vendors.

3. One CSL version has no bars.:shock: Obviously, they placed control in the travel limit, springs, and shocks AND lightweight.

4. A modern approach would be coil over, adjustible with corner balancing.

5. I guess it would be interesting to know what the shock travel limit is with different versions of Billys or Boge. I know this is a big deal with Porsches as shocks can jack up a suspension at rest.

6. Anyone who wants to improve their handling needs to go through and first make certain what they have to start with is within wear tolerances. You might just find your answer or part of it.

7. I recall early on, one cheap upgrade was to use the Bav bar at 24mm vs. the early bar of 18mm? Bars we have access to are heavy. Currently there are better and lighter materials for this.

8. Someone more familiar with Alpina, etc, should chime in about what they did back when on customer's road cars vs. the race prep. My guess is that BMW already new before the last CSLs were tweaked or retweaked what worked. But that was then.
 

rsporsche

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the current springs from lajolla and korman are both straight coils (no-progressive). i know for a fact that korman's are as Carl Bennett told me so. the pics from the lajolla website appear to be straight coils.

my guess is that the ST springs that Doug has are progressive ... since Doug gave us the specs on the ST bars, perhaps he can tell us about the springs in the pkg - then we can find if they were applicable to other BMW ... since they no longer list the e9coupe in their product data.

coil overs - anybody know who makes coilovers for our cars? anybody racing with that type of setup - since you can generally get different spring types
 

decoupe

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the current springs from lajolla and korman are both straight coils (no-progressive). i know for a fact that korman's are as Carl Bennett told me so. the pics from the lajolla website appear to be straight coils.

my guess is that the ST springs that Doug has are progressive ... since Doug gave us the specs on the ST bars, perhaps he can tell us about the springs in the pkg - then we can find if they were applicable to other BMW ... since they no longer list the e9coupe in their product data.

coil overs - anybody know who makes coilovers for our cars? anybody racing with that type of setup - since you can generally get different spring types

My springs are what CN used to sell before ST stopped making them. I believe they are slightly lower and stiffer then Carl's latest offerings but no way to confirm that - they are not progressives.

Ireland Eng makes a coilover conversion kit for both the e9 and e10 (2002) that Shannon Essex uses for which a wide variety of springs are available. I'm considering this and here's a link to a previous discussion http://www.e9coupe.com/forum/showthread.php?t=9277 Then there is the Variant 3 from KW for $3500 that I would love someone to buy and tell us everything about it - http://www.vividracing.com/catalog/kw-variant-coilover-kit-bmw-coupe-e9-30-cs-7176-p-144320.html

Doug
 

Arde

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Saturday morning with an empty shop was great for sway bar install. Time to go over all the input from others (all printed beforehand) and it was very useful. Front and rear are installed, handling has improved a lot, the impulse response feels like moving sideways instead of rolling, which is great.

Will measure roll with the iphone app probably tomorrow when I get a willing passenger to operate the iphone and camera.

Here are some pictures. Thanks for all the help.
 

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Bwana

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^^^ A lot more attractive than the ugly electric lime green bars I got from La Jolla. F%$^ing lit up the underside of my car, felt like I should have had chromed coffee can mufflers sticking out the back.......They couldn't tell me why theie supplier had such bad taste in hardware color. Primed and painted they look OK, hope the paint lasts :mad:
 

deQuincey

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Saturday morning with an empty shop was great for sway bar install. Time to go over all the input from others (all printed beforehand) and it was very useful. Front and rear are installed, handling has improved a lot, the impulse response feels like moving sideways instead of rolling, which is great.

Will measure roll with the iphone app probably tomorrow when I get a willing passenger to operate the iphone and camera.

Here are some pictures. Thanks for all the help.

good for you ! congrats !

just for the records, would you be so kind to detail the items that you bought for this setup

i will appreciate !

regards
 

decoupe

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^^^ A lot more attractive than the ugly electric lime green bars I got from La Jolla. F%$^ing lit up the underside of my car, felt like I should have had chromed coffee can mufflers sticking out the back.......They couldn't tell me why theie supplier had such bad taste in hardware color. Primed and painted they look OK, hope the paint lasts :mad:

After the black paint started to get some chips my ST sway bars were - lime green underneath. I try not to look at it.
 

rb1971

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^^^ A lot more attractive than the ugly electric lime green bars I got from La Jolla. F%$^ing lit up the underside of my car, felt like I should have had chromed coffee can mufflers sticking out the back.......They couldn't tell me why theie supplier had such bad taste in hardware color. Primed and painted they look OK, hope the paint lasts :mad:

Funny I like that color on the sway bars. It's like when a lady (or maybe less than a lady...) is wearing a garter belt. You get a glimpse of fun but not a statement.

Of course my ride could not be accused of being original.
 

Nicad

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Funny I like that color on the sway bars. It's like when a lady (or maybe less than a lady...) is wearing a garter belt. You get a glimpse of fun but not a statement.

Of course my ride could not be accused of being original.

Nice way to put it!
 

Arde

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good for you ! congrats !

just for the records, would you be so kind to detail the items that you bought for this setup

i will appreciate !

regards

There are two items involved:

1) The ST sway bar kit 52015 includes front and rear sway bars plus all the new brackets, bushings, bolts, washers, grommets, nylocks, spacers you need including grease. The bracket bushings are split so that makes life easier.

2) Part 31-35-1-118-390 is an alternate bracket for the front that is a bit smaller (partially visible in the attached picture).

The rear was straightforward, the only decision was how to keep the ebrake from being pinched by the sway bar, so we added a plastic tie-wrap to the existing wire hangers. I ended up using the understeer hole (the near one) for the rear adjust and some day I will play with that just to understand the physics.

The front was trickier due to the need to drop the subframe 1/2 inch and the challenges in removing and replacing the bracket. Heeding the warning from our Australian friend we decided to use bracket 2) instead of the kit bracket. The hole of either one would have required a bit of enlarging to really align, so we did that instead of compressing or deforming the bracket.

Tightening the kit's hex bolt from below is impossible, that is why the factory bolt is Allen. We tightened the nut from above in a slow tedious process but got to use the new and longer bolt.

All in all the parts fit but the second time you install it is probably easier than the first...


I think the hardest part of this job seems to be that ST does not stock the kits, so we may need Stan to step in and fix this availability problem :)
 

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Arde

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OK, project complete, time to close this thread with hard data. ST sway bars reduced body roll at highway speeds in half.

Went from 12 degrees at 75mph to 6 degrees, and from 17 degrees at 85mph to 8 degrees.

Instrumentation was crude, but intuitively confirmed by the feel of the car. Recommended upgrade for sure. Thanks for all the advise received here on options and installation.

Oh, the 1st and 2nd gear acceleration of Verona read a bit above 1/3 of g, which means it cannot go up vertically, bummer.

Here are the pictures:
 

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glenn in encinitas

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Nice closure using objective measurement Arde! BTW: I have the CN bars/springs with Bilstein HDs and Alpinas on a 2800. The setup simply kills the stock setup on my CSL. I did not have the install hassles some described since they were installed at LJI.
 

deQuincey

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that was good, real data !
the result is fabulous !
thanks

you know the funny thing, the app used was developed by a guy in spain...

arde, a question, do you think it will work in the ipad ? i have the version number2
i do not have an iphone
 
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Arde

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deQuincey according to the search engine the app also works on ipads as long as the OS is appropriate. It would be great to see that bigger screen mounted on your console...
 

snj5

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Update

Update: apparantly the manufacturer has let loose a lot of swaybar sets to distributors this week according to Carl at Korman. Should have mine is a couple of weeks. Tomorrow the Korman lowering springs and Bilsteins going in with s/s brake lines and new rotors and pads.

Might be time to get a set if anyone is interested.

Between this and my Alabama/Norte Dame ticket for Monday I am headed for the financial doghouse with 'she who must be obeyed'. As my college daugter says, "YOLO". :)
 

Arde

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Well, I guess my thread did more for this manufacturer than 5 Superbowl commercials...
 

snj5

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Are you putting in some negative camber plates-these help the geometry when lowering

Not initially. Not because of some intelligent cogent plan, rather many of the threads here did not mention them, Korman didn't say I needed them and I didn't think to get them. If it comes out silly will get a set for sure. Will post before/after pics hopefully.
 
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