If anyone has a set of OE swaybars off their car, please, please, please measure them for me. The attached picture shows you want I need. Front and rear, please. And just give me the lengths of A, B, and C ignoring any wiggles and curves. I'll deal with those later. Or, if you'd like to make a guess of the true lengths of B and C, including the wiggles, that's great, but also provide the straight-line distances, as well, please.

To be clear. A is how far the hole in the arm is from a straight line through the main part of the bar. (It gives us the leverage of the arm, if that helps to explain what I need.) B is the length of the arm from the outer bend to the hole ... the distance from the bend to the hole, ignoring the curves in the arms. (Because the arms are not at a right angle to the main section, this distance must be greater than A.) And C is the length of the main section.

If you'd like to verify the diameters of the bars while you're at it, that would be great, too.

Please don't make me crawl under a very dirty car in 20*F weather.

 

i got 23.3 mm for the bar diameter using a digital caliper. i can try to measure the rest of the stuff this weekend.

 

Rear:

Diameter is 23mm

 

Travis -

Thanks very much, but the critical bend for the calculations is the last one, outside of the where the brackets hold the bar to the chassis. Also, the leverage measure (A) should be the shortest distance from the hole to the line that goes through the center of the bar as it go through the brackets, ignoring any wiggles in the bar between the brackets.

I attached a copy of your picture with the needed lengths in green.

But, again, thanks.

 

well, it seemed easier than it was. a rigid tape measure trying to measure a sway bar attached to car is a bit challenging so dont use my numbers for anything important:

best numbers i could get:


the 31.5" is from just outside the main mounting points.
7.75" was from the endlink bolt to the first curve.

the 6.75" is the one im least sure of since the end point is a virtual line.

hopefully it helps or lines up with others results.

 

Thanks! So the rear bar has a (raw) single-wheel rate of around 470 #/inch; combine that with a motion ratio of about .57 and it's contributing about 150 #/inch to the single-wheel wheel rate. The spring is about 200 #/inch (3.5k) with a motion ratio of .84; so that's 140 #/inch at the wheel for the spring. Wow! That's actually rather surprising to me. More than half of the rear single-wheel rate (and, therefore, more than two-thirds of the rear roll rate) is coming from the bar. No wonder we break end-links back there.

OK. Front? (Not to be too demanding.)

 

Woo hoo. Validation always feels nice. I found this when searching for something else:
http://www.maperformance.com/perrin-...l#.UQyRfPI8CSo

Note that it says that the OE rear swaybar is 494 #/inch. That's darned close to the 470 we got, so I'd say that MomoStallion did a good job measuring.

 

Well that's good news. I wish I understood it better.

The front seems quite a bit harder to measure. I do have plans to upgrade mine but won't be till later this year. Surely someone has their stock bar off the car.

 

On the car, the only good way to measure the front would be the "plumb-bob" method. You attach a weight (made of lead, in the past, hence the label "plumb") to a string and hold the string to critical points on the bar, marking the floor directly beneath. You also measure the distance to the floor in each case. When you have the four point marked (i.e., the ends and corners of the bar), you drive the car off your markings and measure them. When the height differences are not all equal, you do a little trig to get the right values.

If that sounds like a pain, it is, but imagine doing that for every critical point of the suspension on an entire car. That's what I did for 2G DSMs.