I Need Some Suspension Help

[Polygon]

I'm really excited with DJ's tubular control arms and Brian's K-member. I will be buying both. Just waiting for Brain the get the sway bar mounts figured out. Anyhow, it's nice to see the some people tackle the market for those of us who like to corner. However, this leaves me with some questions.

1. With DJ's control arms, he says "custom kingpin dimensions to suit customer application." How do I know what dimensions I need?

2. I was over at PolyBushings to get some bushing lube when I noticed that they sell a rear sway bar. Just curious if this is really needed or beneficial.

The car this all will be going on is a 1989 LeBaron GTC. I have Konis with Eibachs. And I have Chris's adjustable track bar.

[Polygon]

Is anyone running the PolyBushings rear K sway bar?

[GLHNSLHT2]

might be helpful in an AutoX situation. But for road course or canyon carving I'd just stick with the solid stock bar and maybe a panhard bar upgrade. IMO these cars are PLENTY tail happy with the right alignment to give the front end it's grip that it's missing out on.

[Polygon]

I assume you mean the stock front bar with the CS Racer track bar and no rear bar? Also, what alignment settings would you suggest? I will take it to auto-x but I LOVE to do some canyon carving and I would love to get it out to the track as well.

[GLHNSLHT2]

No I mean the solid "stock sway bar" in the rear axle. Yes I'd upgrade to the CS Racer style panhard bar. Read my write up in the knowledge center. http://www.turbo-mopar.com/forums/co...s-for-FWD-cars

[Polygon]

Oh yeah, hehehe. I forget about that thing. Oh, I and I already have the CS Racer panhard bar. Thanks for the article, that's perfect! Now, to adjust the camber in the rear... how do they do that? Don't they have to add shims under the spindle?

[tryingbe]

I had the polybushing bar on my Daytona. Worked good for me.

[GLHNSLHT2]

The PB bar just upgrades the bushings, doesn't take the flex away from the crappy metal itself flexing.

[Vigo]

I think he's talking about the rear sway bar and you're talking about the poly track bar bushings.. right?

I have the aftermarket rear sway on my aries and have another for my dynasty. To me it comes down to how fast you want to be going when you take turns. If you primarily would be autoXing and not throwing it into curves at higher speeds (60+mph) id get the swaybar. If you want to drive really fast on the street, id skip it. Id rather have limit understeer on the street by a mile, and its still definitely possible to spin out in a higher speed curve if you do it wrong, even with stock rear bar.

[tryingbe]

I had their anti-sway bar.

http://www.polybushings.com/pages/swaybarkrr.html

[Polygon]

Yeah, I have the CS Racer panhard bar. I'm talking about the sway bar itself. I'm really considering this now. However, I had another idea.

Boxing in the bottom of the axle. Seems like that would add some strength to the axle as well. And then toss the sway bar on. The car will be a street car that I take to auto-x and the track once and a while.

[Johnny]

I also make a panhard bar.....
http://polybushings.com/pages/1095.html

[Vigo]

Welding the axle AND adding the swaybar is something you should definitely NOT do unless you want this to be an autox car and not turn fast on the street. In all the k-cars ive had, the number of times i spun them out was directly proportional to how much roll stiffness i added. The first time i EVER spun a k-car was after welding the axle. The car ive spun the most is the car i welded the axle AND put the external sway bar on.

Your car is too valuable to risk on overkill rear suspension. Do you actually, actively WANT more roll stiffness than it already has, or is this more of an exploratory question?

[turbovanman²]

I've heard bad things can happen if you box the rear axle in. If you do that, you take away from its flex and basically make it solid.

[black86glhs]

If you put the sway bar in, you still get a small amount of bushing deflection. This should be less stiff than welding a plate across the bottom. Make sure your tires are sticky. If they aren't sticky enough to go with the added roll stiffness.....spin city.

[Vigo]

In my experience welding the plate (ive done either 2 or 3 axles, cant remember) is a smaller change than doing the external swaybar. The axle tube still bends.. The U-channel you are boxing is less torsionally rigid than the actual bar inside it so boxing it in is not a night and day change. I have always wanted to experiment with stacking plates and clamping them with U-bolts but ive never gotten around to it.

[black86glhs]

In my experience welding the plate (ive done either 2 or 3 axles, cant remember) is a smaller change than doing the external swaybar. The axle tube still bends.. The U-channel you are boxing is less torsionally rigid than the actual bar inside it so boxing it in is not a night and day change. I have always wanted to experiment with stacking plates and clamping them with U-bolts but ive never gotten around to it.

True, I forgot to take into account the size of the swaybar. The thicker, more rigid bars would do like you said. Thanks for the correction.

[Johnny]

Then, you could always order a smaller rear bar instead.

[Murphy]

I got the polybushings rear swaybar. I like it. I've never spun the car. I've auto-x'd it and driven it pretty hard on the street

[black86glhs]

Then, you could always order a smaller rear bar instead.

Exactly where I was going with my posts.