Suspension suspense

[Arde]

Wow, lots of surprises down the path of replacing sway bars.
Who has a setup that is stock with Bilsteins HD plus upgraded sway bars and is happy with it? Can I drive your car for 10 minutes?

 

[adawil2002]

Wow, lots of surprises down the path of replacing sway bars.
Who has a setup that is stock with Bilsteins HD plus upgraded sway bars and is happy with it? Can I drive your car for 10 minutes?

I am very happy with Billy HDs, Carl Nelson (Suspension Techniques) F-28mm & R-22mm anti-sway bars, and Carl front springs & stock rears. Car went from a soggy sloppy handling Buick to an amazing handling BMW. Handles as well as my M3 without the harsh ride, as a grand touring coupe should.

If you were in the neighborhood, weather permitting, you'd be welcome to drive the car.

FYI, with the front bar, have to drop the front subframe an inch or so to get the the bracket, bushing and bar to fit. Grease bushing, mount bar, snug bracket, torque subframe, center bar, grease and install end link bushings, then tighten brackets.

 

[decoupe]

I am very happy with Billy HDs, Carl Nelson F-28mm & R-22mm anti-sway bars, and Carl front springs & stock rears. Car went from a soggy sloppy handling Buick to an amazing handling BMW. Handles as well as my M3 without the harsh ride, as a grand touring coupe should.

If you were in the neighborhood, weather permitting, you'd be welcome to drive the car.

Did Carl have a recommendation as to which hole to use on the rear adjutable sway bar linkage?

Doug

 

[rsporsche]

Arde,

a while back, i was looking at the suspension techniques catalog ... and for some reason, i have an ebay auction tagged for a set of bars for a 79 to 81 528i (e12) that also fits a 77 to 82 630csi / 633csi (e24). the set product number is 52015. seems like i remember reading that these bars fit our cars - but i can't lay my hands on whatever i read that said this ... so please don't take my word for it. interesting enough, i just looked on carl nelson's site, and i didn't see the swaybars listed.

i bought a used ST front bar from Mario at VSR a while back, but it doesn't have any of the mounting hardware.

so question to anybody reading this thread - has anybody corresponded with ST to find out if anything they make still fits our cars? i will try to reach out to them this week and ask the question. if the answer is that they don't make anything - i will ask how many units they would need in a group order to revive the product, and then we can see if we have enough interest to do it. i have sent an email to ST - will update the group on what i find out

scott

 

[adawil2002]

Did Carl have a recommendation as to which hole to use on the rear adjutable sway bar linkage?

Doug

I used the hole which was closest to the end link hanging loosely from what I recall, made sure the bar didn't rub or touch anything. My E-brake cable is above the rear bar.

 

[rb1971]

Wow, lots of surprises down the path of replacing sway bars.
Who has a setup that is stock with Bilsteins HD plus upgraded sway bars and is happy with it? Can I drive your car for 10 minutes?

I have Carl's swaybar package and the HD Bilsteins and love it. I've got some other minor suspension mods, but if you can come to SF (or maybe the office park just north of the airport next weekend), you can, um, experience it but I can't promise driving.

 

[decoupe]

I bought a 28/22mm ST sway bar set - I'll check to see if I have a model number.

 

[Mike Goble]

It is interesting to see the differences:

Ireland: f/r 28.5mm/22mm
Korman: f/r 22mm/19mm

Is there such a thing a different bar materials? The diameter difference between the front bars above seem rather large.

The stiffness of the bar is proportional to the 4th power of the diameter. If the above listed bars are of similar material and the lever arms are the same, the 28.5mm bar will be 2.8x as stiff as the 22mm, and the 22mm bar will be 1.8x as stiff as the 19mm bar. A small change in bar diameter will produce a large change in stiffness. When you get into hollow bars there are other factors to consider.

 

[johanaxelson]

The stiffness of the bar is proportional to the 4th power of the diameter. If the above listed bars are of similar material and the lever arms are the same, the 28.5mm bar will be 2.8x as stiff as the 22mm, and the 22mm bar will be 1.8x as stiff as the 19mm bar. A small change in bar diameter will produce a large change in stiffness. When you get into hollow bars there are other factors to consider.

That is assuming they are made from the same kind of steel with the same elasticity (or whatever the English term is)

 

[snj5]

Spoke with Carl at Korman today - seems they have gone to 28/22 bars as well. He also talked me into a set of matched springs for the bars and HDs. Everything has to match.
I gotta stay off the phone. He did, however, talk me out of a quick ratio manual steering box.

 

[decoupe]

ST Suspension (KW Automotive is the same people) still sell the 28/22mm set as part number 52015 for $404USD. It isn't listed on the website but still shown in their product list according to the agent I spoke to but he did say that others will sell it for less as they charge MRSP with no discounting.

If you need parts for incomplete sets (rporsche) they can supply them but best to call the 18004453767 number and speak to sales.

Doug

 

[Mike Goble]

That is assuming they are made from the same kind of steel with the same elasticity (or whatever the English term is)

That's why I wrote - " If the above listed bars are of similar material and the lever arms are the same..."

The modulus of elasticity doesn't vary much among varieties of spring steel.

http://www.planetspring.com/pages/properties-of-common-spring-materials-high-temperature-springs.php

 

[rsporsche]

ST Suspension (KW Automotive is the same people) still sell the 28/22mm set as part number 52015 for $404USD. It isn't listed on the website but still shown in their product list according to the agent I spoke to but he did say that others will sell it for less as they charge MRSP with no discounting.

If you need parts for incomplete sets (rporsche) they can supply them but best to call the 18004453767 number and speak to sales.

Doug

thanks Doug, i have the email address of one of the technical people. i spoke to him today about e9 bars - they don't make them anymore, it would take an order of 100 to get them to remake them. the 52015 set is for an e12 and an early e24. not sure if they would fit on an e9

 

[rsporsche]

I bought a 28/22mm ST sway bar set - I'll check to see if I have a model number.

Doug,

can you send me a pic of the front bar and detail pix of the attachments please to scottperkins <at> bellsouth <dot> net. if you do find the model number - i would like to know

cheers
scott

 

[decoupe]

Scott:

I sent what I had here at the house - rear instructions and parts list. I'll see if I have the list for the front at the shop and take some photos.

Doug

 

[rsporsche]

thanks a lot Doug ...

for everybody else, the rear bar from ST is 50115 ... which is the rear bar in the 52015 set for the e12 and early e24. if we verify that the front bar is 50015 ... we will post here so that everybody will know.

 

[johanaxelson]

That's why I wrote - " If the above listed bars are of similar material and the lever arms are the same..."

The modulus of elasticity doesn't vary much among varieties of spring steel.

http://www.planetspring.com/pages/properties-of-common-spring-materials-high-temperature-springs.php

Sorry Mike, my bad. Was reading too quick I guess.

 

[rsporsche]

thanks a lot Doug ...

for everybody else, the rear bar from ST is 50115 ... which is the rear bar in the 52015 set for the e12 and early e24. if we verify that the front bar is 50015 ... we will post here so that everybody will know.

okay guys - its official, the front swaybar from suspension techniques is 50015 ... so the set is the 50215. so if anybody wants these swaybars - you can still buy them. by the way, i've seen a set for sale on amazon.com as well as ebay - both new and both for less than $350.

 

[Arde]

okay guys - its official, the front swaybar from suspension techniques is 50015 ... so the set is the 50215. so if anybody wants these swaybars - you can still buy them. by the way, i've seen a set for sale on amazon.com as well as ebay - both new and both for less than $350.

OK, but from what I read installing them is a bit of an art, and not clear if it is recommended to install with stock springs vs. going for a tested combo.

 

[decoupe]

Quote:
Originally Posted by rsporsche
okay guys - its official, the front swaybar from suspension techniques is 50015 ... so the set is the 50215. so if anybody wants these swaybars - you can still buy them. by the way, i've seen a set for sale on amazon.com as well as ebay - both new and both for less than $350.

Originally Posted by Arde
OK, but from what I read installing them is a bit of an art, and not clear if it is recommended to install with stock springs vs. going for a tested combo.


Arde,

I installed the #52015 Front/Rear 28/22mm ST sway bars and didn't find them particularly difficult so not sure what you have been told. The routing of the e-brake cable past the rear bar while feeding the bar over the driveshaft was awkward and took a bit of trial and error (which side is up) but does fit - knowing this is possible should make it easier versus me wondering if it was going to work.

The second part of the question as to whether it's worth doing with stock springs versus the sporty spring/shock combo. I think there would be a benefit even if the springs are stock by reducing body roll but not to the degree that the full sport setup would give. I don't think there is a negative outcome and you could always try it (before deciding on going further with lowering springs and HD shocks) and if you don't like - it re-bush the stock sway bar set and sell the ST 52015.

Doug