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Discussion Starter #1
I just got my BMR rear sway bar installed on my wagon, which still has the stock front sway bar. I think the BMR bar is 1.5" in diameter. It's got stock (I think) springs, Bilsteins, and relatively sticky 255/45R20 high-performance all-seasons.

I took a couple of corners and the car has gone from understeer to either oversteer or A LOT of oversteer. Obviously I need a larger front sway bar to balance out things. I'd prefer neutral to slight oversteer bias.

Options:
BMR - 32mm / 1.26" solid - $209.95 - https://www.bmrsuspension.com/?page=products&productid=39&superpro=0

Spohn - 33.3mm / 1.31" solid - $212.50 - https://www.spohn.net/shop/1978-1996-GM-B-Body/Suspension/Sway-Bars-Accessories/Front-Sway-Bar-Solid-1-516-4140-Chrome-Moly.html

Hotchkiss - 36.5mm / 1.44" hollow - $305.99 - https://www.hotchkis.net/product/1978-1996-gm-b-body-front-sport-sway-bar-sedan-from-hotchkis-sport-suspension/?mk=&yr=&md=&sm=#overview

I'm inclined to go with the BMR as it's the smallest (assuming that all other things being equal, a smaller front sway bar ought to preserve a little of the tail-happiness of the BMR rear sway bar), and because I'm hoping that getting sway bars from the same company will mean that they are designed to work well together.

What do you guys think?
 

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I just got my BMR rear sway bar installed on my wagon, which still has the stock front sway bar. I think the BMR bar is 1.5" in diameter. It's got stock (I think) springs, Bilsteins, and relatively sticky 255/45R20 high-performance all-seasons.

I took a couple of corners and the car has gone from understeer to either oversteer or A LOT of oversteer. Obviously I need a larger front sway bar to balance out things. I'd prefer neutral to slight oversteer bias.

Options:
BMR - 32mm / 1.26" solid - $209.95 - https://www.bmrsuspension.com/?page=products&productid=39&superpro=0

Spohn - 33.3mm / 1.31" solid - $212.50 - https://www.spohn.net/shop/1978-1996-GM-B-Body/Suspension/Sway-Bars-Accessories/Front-Sway-Bar-Solid-1-516-4140-Chrome-Moly.html

Hotchkiss - 36.5mm / 1.44" hollow - $305.99 - https://www.hotchkis.net/product/1978-1996-gm-b-body-front-sport-sway-bar-sedan-from-hotchkis-sport-suspension/?mk=&yr=&md=&sm=#overview

I'm inclined to go with the BMR as it's the smallest (assuming that all other things being equal, a smaller front sway bar ought to preserve a little of the tail-happiness of the BMR rear sway bar), and because I'm hoping that getting sway bars from the same company will mean that they are designed to work well together.

What do you guys think?
How big is the front swaybar on your car now?
 

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Discussion Starter #3
It’s the stock wagon front sway bar, so something tiny!

Google says it’s 28mm.
 

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Why did you install that largish rear bar?
 

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Probably selected the single worst rear bar for your application. Installing the factory bar in it's place will likely make a huge improvement if not elimination of any oversteer issue(s)....
 

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Bigger not always better. I am running the rear 9C1 bar and actually took out the front 9C1 bar and ran a civi Caprice front bar. GM loved that 1/8" bigger front bar to induce understeer. Same size or slightly larger rear will get you close to neutral.
 

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Probably selected the single worst rear bar for your application. Installing the factory bar in it's place will likely make a huge improvement if not elimination of any oversteer issue(s)....
Not to be picky, but there is no rear factory bar for our wagons.

I use a 70'S B body rear bar for sedans which fits perfectly. Part of the Pontiac RTS option.............radial tuned suspension............ which was a big deal back then. Only available for sedans, coupes, conv, not wagons.

I think there is a 91 - 96 limo or commercial option with rear bar, but don't think it fits wagons. The FW crowd will chime in.
 

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Try contacting BMR, tell them which rear bar you got, and ask for a recommendation for a front bar. Also see what else they recommend to get you where you want to be. I think if you start guessing on your own you won't be happy.
 

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While I am guilty liking a lot of bar , that is a LOT of bar! !

When doing your front to rear bar ' figgerin" remember to must take into consideration tubular vs solid
http://www.auto-ware.com/calcs/swaybar.htm

While millions of cars use the strap to lower arms type rear bar, it is less than optimal from a design standpoint.

One thing I noticed in my case , with poly type rear arms , the susp would seem to go into bind as it rolled which will spike outside loading.

I since changed to a bearing type arm and that tamed the , at the limit, oversteer sensation.

I "only " have a 1.25 solid rear bar and 1.25 solid front but the front is the short arm "F" bar repositioned back so it "acts" like a large "B" bar.

On the street, I am happy, but will note even with the front disconnected on the way to the drags, it is not evil oversteer.

The wagon is tail heavy and add the pendulum effect of the tail gate WAY back there, part for part is going to be more tail happy than the sedan.

While I live in a road racing environment, I have not road coarsed my wagon and must defer to people here with experience for actual "B" body track use

On the street, if you are keeping that rear bar, I think you are going to need some more front bar.
My gut would look at the Spohn if it is a true "B" body arm length

Take the above for what it is, an opinion

Gerry
 

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FWIW - I used Addco rear bars (1") with stock front bars on my Buick and Chevy wagons, along with a front alignment optimizing negative camber and positive caster, and they handled and rode beautifully. I think a 1.5" rear bar might be good if you're into drifting. >:) Otherwise, if you must use your BMR rear bar, I'd go with the Spohn (partially for financial reasons) and start with something close to stock alignment settings, keeping in mind that these cars can use a fair amount of positive caster to give a bit more road feel and response. Fine tune with tire pressure. I wouldn't use more than a 4psi difference f/r, as if it takes more than that, the suspension is still not balanced and needs to be corrected. Don't forget that you can resell the BMR bar; someone will want it.
 

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FWIW - I used Addco rear bars (1") with stock front bars on my Buick and Chevy wagons, along with a front alignment optimizing negative camber and positive caster, and they handled and rode beautifully. I think a 1.5" rear bar might be good if you're into drifting. >:) Otherwise, if you must use your BMR rear bar, I'd go with the Spohn (partially for financial reasons) and start with something close to stock alignment settings, keeping in mind that these cars can use a fair amount of positive caster to give a bit more road feel and response. Fine tune with tire pressure. I wouldn't use more than a 4psi difference f/r, as if it takes more than that, the suspension is still not balanced and needs to be corrected. Don't forget that you can resell the BMR bar; someone will want it.
The rear bar I referenced above in post #8 is also 1", and I am using the stock front (1 3/16"). Makes a noticeable improvement. Not into racing, but great for my application.
 

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The wagon rear axle is approximately 2" wider than the sedan, hence the need for an aftermarket anti-roll bar. However, an Impala SS assembly will usually squeeze in the space under a wagon, and it includes disc brakes, 3.08:1 gears, Positraction, and a rear bar. The wagon's rear track can be restored with offset wheels and/or spacers, but the drawback to this is that axle load is moved outward, placing increased stress on the bearings and the unsupported axle area outside the bearing. Not worth the effort and expense IMO; the sedan track will do just fine in most cases, and it creates a little more space when removing and replacing a rear wheel. Aside from needing a few fittings and cables, the speedometer/odometer would also need to be recalibrated to the new axle ratio. Acceleration is improved; fuel mileage is not.
 

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Another way of stiffening the rear suspension would be to substitute air or spring overload shock absorbers for the stock ones; I've had good results with these.
 

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Discussion Starter #15
I’m using the BMR wagon bar because one came available on the forum and because my wagon already had BMR LCAs, and I figure it’s about as rare as a unicorn, so I bought it.

Did BMR make a narrower bar for the wagons too?
 

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Discussion Starter #16
Oh wait, I found the for-sale thread, and the seller says he thinks it’s a Helliwig bar. So maybe it’s not a BMR.
 
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