I want to talk swaybars.

[Vicarious]

I used to be into turbo Volvos, and those guys figured out how get aftermarket swaybar performance without the price. Money is a really big factor with these guys. So they put two stock swaybars, one on top another, making one big fat swaybar. With some calculations the double bars are as stif or stiffer than IPD sways (most popular volvo pieces)

Anyone try this? I have a stock 318is sway laying around from my old car, now i just got a 318i and thinking of doing this.

What volvo guys did was they fabbed up steel plates to hold the two sways one on top another.

Another question I have is what other e30 sways are compadible but that are stiffer than my '91 318i ones?

sways like UUC are $400+ seems a bit steep.



heres the link to the turbobricks.com forum thread

http://forums.turbobricks.com/showthread.php?t=9587

[110stx]

IF you can fab up the brackets and so forth to hold two swaybars, and IF the two sways function properly without any preload, etc., then you'd have WAY too much front bar on the car.

Bottom line, with roughly 42 mm of front bar on the car, you'd be plowing like a pig.

Obviously, my $0.02 ... Carry on.

d.hitchcock

[5Toes]

Metric mechanic did this back in the day, here is the article

http://i114.photobucket.com/albums/n279/peperry/CutSprings.jpg

[Vicarious]

IF you can fab up the brackets and so forth to hold two swaybars, and IF the two sways function properly without any preload, etc., then you'd have WAY too much front bar on the car.

Bottom line, with roughly 42 mm of front bar on the car, you'd be plowing like a pig.

Obviously, my $0.02 ... Carry on.

d.hitchcock

It doesn't work like that though, adding 2 bars doesn't simply combine the 2 bars' strengths, its not 21+21=42. Theres actually a an equation that gives you a coefficient. It comes out to some kind of slightly added number.

[Mr. Tasty]

Metric mechanic did this back in the day, here is the article

http://i114.photobucket.com/albums/n...CutSprings.jpg

you posted a cut spring article? anyways, the suspension of the e30 is extremely simple. Why would you want a huge sway in the front?

[george graves]

Another way to say that is that a 42mm bar is way more than twice as stiff as a 21mm bar. Where as (just a guess) a 25mm bar might be twice as effective as a 21mm bar,

[nando]

I can't find my spreadsheet but somewhere in there you multiply by the power of 2 when you increase swaybar *diameter*. But he's not talking about increasing the swaybar diameter - he's talking about using two swaybars of the same diameter together.

each swaybar has a given amount of force that takes to bend it at the swaybar link mount point. Let's call that force N. If you increased the size of the swaybar, it's not linear, it's something like (old size + increase)^2 = N.

Using two swaybars* is* actually just N+N (assuming the geometry works as in the 1st reply above), not the original equation which multiplies the value by ^2. You can't apply that equation because the diameters of the bars aren't changing, you're just using two of them at the same time.

now, I'm not saying this is a good idea. a better way to effectively increase the swaybar stiffness is to decrease the leverage that the suspension has over it. just drill a hole closer to the main part of the swaybar and you'll increase the stiffness without touching the diameter.

[foofopps]

Isn't the true answer to this guys question a vert front sway bar. ie. He wants to know what a cheap solution is for a better front sway bar.

[5Toes]

No if you actually READ the article it discusses sway bars

[pantelones]

Isn't the true answer to this guys question a vert front sway bar. ie. He wants to know what a cheap solution is for a better front sway bar.

The route I went was...

Vert 21mm front $65
Adjustable I.E. links $60
fresh rubber mounts $20

M3 14.5mm rear $25
Fresh end-links and rubber mounts $20

Total spent $190