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Discussion Starter #1
Hello everyone. I have read many threads about this and some say we must upgrade the LCA's before installing bigger sway bars. Others say that it is not needed. Can anyone chime in on this topic? I would like to rid the car of some of the body roll, but the car will NEVER be autocrossed or tracked. My SS is just a fine commuter car. I drop the kids off at school and commute to work and get groceries in it. It is a 3rd family car and toy. Must I do the LCA's before adding a bigger front and rear roll bar?
 

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The short answer is no,but new trailing arms do offer benefits of their own. As do replacing the body bushings...
 

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... Must I do the LCA's before adding a bigger front and rear roll bar?
As 1slow- states, no. There are no state or federal laws governing it. However, just as you would not try to fire a .357 out of a BB gun it visually appears frightful to be loading the forces of a stout bar against such flimsy stampings. And as also referenced, aftermarket arms (and their upgraded bushings) will curtail lateral movement that jacks with the steering line.

Also to your question, not a real connection between a bigger front bar and rear LCAs as far as I can see. Except that you would not want to add a bigger/better front unless/before doing the back anyway (which is what requires the better arms) unless you want even more understeer than these tubs come with stock.
 

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If you're not driving, beating the crap out of it, you'll be fine. I've logged over 150k on the 91 with stock arms and the 1 1/2" HO bar. Only failure was one side from rust a couple years ago of the bracket that goes inside the arm. My driving is just like you described.
 

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Discussion Starter #5
... Must I do the LCA's before adding a bigger front and rear roll bar?
As 1slow- states, no. There are no state or federal laws governing it. However, just as you would not try to fire a .357 out of a BB gun it visually appears frightful to be loading the forces of a stout bar against such flimsy stampings. And as also referenced, aftermarket arms (and their upgraded bushings) will curtail lateral movement that jacks with the steering line.

Also to your question, not a real connection between a bigger front bar and rear LCAs as far as I can see. Except that you would not want to add a bigger/better front unless/before doing the back anyway (which is what requires the better arms) unless you want even more understeer than these tubs come with stock.
Thank you very much. I appreciate your response. The longer LCA's will center my wheels too, right?

If you're not driving, beating the crap out of it, you'll be fine. I've logged over 150k on the 91 with stock arms and the 1 1/2" HO bar. Only failure was one side from rust a couple years of the bracket that goes inside the arm. My driving is just like you described.
Thanks for the comment. My car is thankfully rust free so I should be good. I'll change the LCA's soon, but not now. I gotta get some bars tho. This fat girl leans too much. Up and down movements are surprisingly controlled. Side to side is another story. My new SRT has no lean, roll or pitch. None. At all. It's different driving this SS, but I respect its heritage and old school charm. It's legendary Americana.

But theoretically speaking, if a stock LCA failed while I was driving on the freeway, would I die? Lololol. Seriously. Would I? What would happen? Thanks to everyone for the replies. I'm learning a lot here.
 

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Be careful... I snapped one of the factory LCA with a HO 1.5" bar on my car. I was pulling into a parking lot taking the angled driveway at a slant and the twisting of the car as I pulled in snapped the lower control arm in half. Was about 200 miles into the new sway bar... If you never twist the frame you MAY be OK.. But you certainly don't want to do like I did and snap that sucker. Your getting a tow bill home for that one...

Make sure you get ones designed to be used with the larger sway bar if you go that route. And yes longer ones will center the rear tire but you also need adjustable uppers when you do it so you can adjust the pinion angle to the correct angle otherwise your axle won't be lined up and you will tear up the u-joints quickly.
 

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Discussion Starter #7
Be careful... I snapped one of the factory LCA with a HO 1.5" bar on my car. I was pulling into a parking lot taking the angled driveway at a slant and the twisting of the car as I pulled in snapped the lower control arm in half. Was about 200 miles into the new sway bar... If you never twist the frame you MAY be OK.. But you certainly don't want to do like I did and snap that sucker. Your getting a tow bill home for that one...

Make sure you get ones designed to be used with the larger sway bar if you go that route. And yes longer ones will center the rear tire but you also need adjustable uppers when you do it so you can adjust the pinion angle to the correct angle otherwise your axle won't be lined up and you will tear up the u-joints quickly.
Damn. So I need Upper and Lower LCA's? That's more $$$$$. I promised myself I wouldn't mod this car but that's not working well for me. Ok, do you suggest any specific brand that may come in a set at a reasonable price? I gotta get rid of the body roll, then I'll stop modding. I promise.
 

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Damn. So I need Upper and Lower LCA's? That's more $$$$$. I promised myself I wouldn't mod this car but that's not working well for me. Ok, do you suggest any specific brand that may come in a set at a reasonable price? I gotta get rid of the body roll, then I'll stop modding. I promise. :D
I didn't catch what you're driving, but extendeds are not used on Fleetwoods, and I'm not certain of RMS. And yes, they need to be installed as a set of uppers and lowers for the reason stated. I know of no reasonably priced new sets, and would hold out for something used FS. While likely still not floating around, do a little research on one or two brands 10 years ago that had poor quality materials or early QC issues.

And you MAY or may not have to change out the axle bushings to fit the new uppers. DO NOT use urethane upper bushings = search 'torsional bind'. 'TsallIgot.
 

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A set of decent shocks (like Bilsteins),and a quality set of spring will reduce "body roll" more than new trailing arms ever will. All trailing arms do (other than locate the rear housing) is limit it's movement from side,to side. Extended length arms are strictly for looks,and offer no advantages over a stock length of comparable construction.
 

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Damn. So I need Upper and Lower LCA's? That's more $$$$$. I promised myself I wouldn't mod this car but that's not working well for me. Ok, do you suggest any specific brand that may come in a set at a reasonable price? I gotta get rid of the body roll, then I'll stop modding. I promise.
Then too, with extended rear arms I'm sure you will need an extended drive shaft. More $$$$$. But, if you don't mind. Why should I? Just something to think about .

Mark: Snowman-33
 

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Then too, with extended rear arms I'm sure you will need an extended drive shaft. More $$$$$. But, if you don't mind. Why should I? Just something to think about .

Mark: Snowman-33
Oh yea, forgot about that part. I also have a longer drive shaft...

You can get by without a longer drive shaft but you have less shaft contacting the gears in the transmission which relates to easier to toast the output mechanism on the transmission.

So you might be better off just getting standard length LCA with the beefier sway bar and call it a day.
 

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OP

as you gather there is a "domino" affect when adding stronger aftermarket parts onto....lets say aged, stamped suspension parts like LCA's.

You can get standard length LCA's and keep the uppers and then put the bigger sway bar on the new LCA's.

I have Hotchkis F&R sway bars and upper & lower rear control arms, standard length. Very happy with ride quality and cornering

Extended lowers to center the rear tire in wheel well never interested me but if that is your desire you will need adjustable uppers to correct the DL (pinon) angle and a new, longer, DS

as part of the "domino" affect....new shocks if yours are still the stock De Carbons would be advised
 

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OP

as you gather there is a "domino" affect when adding stronger aftermarket parts onto....lets say aged, stamped suspension parts like LCA's.

You can get standard length LCA's and keep the uppers and then put the bigger sway bar on the new LCA's.

I have Hotchkis F&R sway bars and upper & lower rear control arms, standard length. Very happy with ride quality and cornering

Extended lowers to center the rear tire in wheel well never interested me but if that is your desire you will need adjustable uppers to correct the DL (pinon) angle and a new, longer, DS

as part of the "domino" affect....new shocks if yours are still the stock De Carbons would be advised
The Domino Effect. I like that. I also forgot about relocating the spring perches.:surprise: Open up the wallet. I smell plastic burning. :grin2:

Mark: Snowman-33
 

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Discussion Starter #14
OP

as you gather there is a "domino" affect when adding stronger aftermarket parts onto....lets say aged, stamped suspension parts like LCA's.

You can get standard length LCA's and keep the uppers and then put the bigger sway bar on the new LCA's.

I have Hotchkis F&R sway bars and upper & lower rear control arms, standard length. Very happy with ride quality and cornering

Extended lowers to center the rear tire in wheel well never interested me but if that is your desire you will need adjustable uppers to correct the DL (pinon) angle and a new, longer, DS

as part of the "domino" affect....new shocks if yours are still the stock De Carbons would be advised
The Domino Effect. I like that. I also forgot about relocating the spring perches.
Open up the wallet. I smell plastic burning.


Mark: Snowman-33
Damn damn damn damn damn. $$$$$$$$$$$$$$$$$$$$$$$$$$$.

Ok well I think I'll just replace the lower arms with beefier ones at standard length, so that I can get better sway bars safely. I don't need to replace the uppers right? Just the lowers at factory length, then I can get bigger sway bars safely. Correct?

With your Hotchkis setup, does it corner flat? Will I immediately notice the difference? How drastic is the improvement? I'm trying to get the side to side "wallowing" out the big girl. Also, what struts/springs are u using?

Thanks again gentlemen!
 

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You're seeing what many here have found. One thing leads to another and then there is something else that comes along. (Domino Effect). My car, a 93 9C1, started out with just replacing the fender and headlight. The engine and trans are out, the front end is completely off, I plan on removing the rear end and I'm trying to figure a way to lift the body. I bought my LCAs from Southside Machine. He was great doing business with and gives a military discount. There are some vendors on here that might give a discount too. You'll have to check that out. I have been very happy with the way my car handled in the past with the 9C1 sway bars so I will keep those. I once took a sweeping 90* from one highway to another at 100+ MPH in a pursuit in my car and it was as if it was on rails. >:) I likes it. I wish I could do more at one session on my car but health slowed me down and now it seems as if Aurthor is visiting my hands. So I can only do a little at time.:crying:

Mark: Snowman-33
 

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Bilstein shocks are likely going to be the top recommendation. I use/recommend Eibach springs,but plenty use/like the Hotchkis springs. Yes,you will notice a difference....
 

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There are a number of different ways to attach the anti roll bar to the arms.

You could have a plate welded to the bottom of the arm (box the arm), with internal tubular pieces at the attachment holes, to keep the arm from collapsing from tightening the mounting bolts, and run short spacers outside to drop the bar a little below the arms for clearance. That may be the cheapest way to beef up the arms. Someone did this a while back, but I don't know who it is, or where the reference thread is.

You could also box the arms, and use a thick piece welded on the bottom of the arm at the mounting points, and drill and tap the holes. The bar bolts screw directly into the bottom of the arm.

If you weld nuts to the inside of the piece boxing the arm, you can bolt directly to the bottom of the arm. The piece boxing the arm might require a slightly heavier gauge for this application, or at least a reinforcement at the attachment point.

You need spacers on the outside to mount the bar on all of the boxed arms.
 

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yes if you go with stronger sway bar and stronger lower control arms you should be fine. Upper control arms really just control the angle of the drive shaft in this case. Your putting all of the torque of the sway bar on the LCA so just replacing those you should be golden.

Also be aware that you MAY see the tires slightly offset. There were threads in the past that explained the frame was drilled wrong for one of the sides and is off by something like a 1/4 inch. ALL of the Bbodies with the Caprice frame have this issue so its not a big deal. Just don't be surprised if you see this. Has been over a decade since I last read that thread. There were ways mentioned on how to compensate for this offset but I don't recall. Again if you check your current setup you will likely see one tire is slightly in front of the other. There may have been some talk of using adjustable LCA to adjust for this or drilling new holes or something but would be best to either find that old thread or not worry about it.

In my car I did not adjust the Spring perch and have had no issues. I bought my car with 100k miles and it currently is sitting with 330k miles and I did the original upgrade of the LCA etc at about 200k miles. I tried firestone air bags which never quite worked right for me probably due to the spring perch misalignment issue. With the lowered springs installed however I have had no issues.
 

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Be careful... I snapped one of the factory LCA with a HO 1.5" bar on my car. I was pulling into a parking lot taking the angled driveway at a slant and the twisting of the car as I pulled in snapped the lower control arm in half. Was about 200 miles into the new sway bar.........
Your arm was most certainly already on the verge of failure.

I know dozens of B-body owners aside from myself who have driven 100K + miles with aftermarket sway bars and OEM control arms with zero issues.

I'm not believing that a fully functional control arm is gonna fail after 200 miles with a aftermarket sway bar.

Jus' sayin'.....

KW
 

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Discussion Starter #20
Be careful... I snapped one of the factory LCA with a HO 1.5" bar on my car. I was pulling into a parking lot taking the angled driveway at a slant and the twisting of the car as I pulled in snapped the lower control arm in half. Was about 200 miles into the new sway bar.........
Your arm was most certainly already on the verge of failure.

I know dozens of B-body owners aside from myself who have driven 100K + miles with aftermarket sway bars and OEM control arms with zero issues.

I'm not believing that a fully functional control arm is gonna fail after 200 miles with a aftermarket sway bar.

Jus' sayin'.....

KW
Hmmmmmmm. I'm so confused now. :(
 
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