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Aftermarket Front A-Arms

While I am making the switch to front coilovers, replacing the hubs and switching to a 35mm adj swaybar with shorter end links, I am thinking about what route to go with the control arms. I will be running square 18 x 11 and an 18mm rear bar. The little track time I have had with the car was with a 22mm rear bar and I did have some push in low to moderate speed turns. Would a taller ball joint, bump steer kit and some toe be enough to get the front end in line or would it be worth the investment to go with a completely different control arm with the previously mentioned upgrades? The car will see very little street use with mostly short drives so I am not worried about NVH.
 
I think most here would say no to a tubular type front control arm.

I'm no expert here but here goes....

If you are getting understeer with a 22mm rear bar, an 18mm is going to make it worse.

I haven't fully wrapped my head around roll center, as I understand it, the taller ball joints up front will raise the front roll center, making it want to understeer more.

I do not want to be giving wrong info so hopefully some of the more knowledgeable ones will chime in soon....
 
I know the smaller rear bar will hurt front grip but between the two I am going for more rear bite with the 18mm. I am trying to do whatever I can to increase front grip while still keeping a soft rear bar. I keep reading about the taller ball joint raising roll center and actually helping front grip. Kenny Brown states this in his description of his "Super-Grip" front control arm package with the tall ball joint. Increased roll center to improve front roll/grip.....trying to figure that out. I have a splitter to help front downforce and maybe the adj front bar I can play with but I would like to see what else I can do within a reasonable budget.
 
I would recommend holding off on the taller ball joints for now. Install the coil overs and don't lower the front end of the car to the point that the front control arms are pointed up toward the spindle. This will keep your suspension geometry somewhat in tact. The added mechanical grip of the coil overs along with the wider tires could solve your issue. Driving technique plays a factor here as well. You want to limit the changes you do at one time to limit the required trouble shooting to correct an issue after the fact.
Here is a good read http://www.s197forum.com/threads/time-to-replace-ball-joints.96978/
 

ArizonaBOSS

Because racecar.
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The aftermarket has not had good luck with front LCAs that are strong enough to hold up to road racing. If you are doing anything there I would suggest the 302S arms (11-14 OEM arms with tall, thread-in ball joints).
 
Thanks for the link......very informative. Even saw Steve Espo on the thread way back in 2013! And yes......I agree with ArizonaBoss that the 302S arms were what I was thinking about. But the whole project seems pretty involved...and expensive. I don't see myself doing that bushing work.....off to Phoenix they go. I may just have a chat with Joe at Phoenix and see what they can recommend. It's only a 25 min drive to the shop.
 
What's interesting in the attached S197 thread is that Vorshlag did not recommend anything other than changing out the factory control arm bushings to urethane. No mention of ball joints or bump steer. With a lowered suspension the tall ball joint and bump steer kit is recommended by most. So many options......
 

ArizonaBOSS

Because racecar.
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For me it was just more about having a very strong and reliable ball joint in-place, and one that can be changed very quickly at the track. I've already damaged one due to contact (unfortunately) and was able to get that fixed and race-ready again in about 20 mins. Not to mention with a press-in, knurled ball joint, you should really only press-in a couple times before the arm gets worn.
 

Mad Hatter

Gotta go Faster
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Going out on a limb a bit.... I put the BMR tubular A arms a while back and have had no issues with them.... Have gone off into the dreaded tire wall and they still seem to be ok. If I remember right @Fabman has them as well? Way lighter thats for sure.
 
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Pleasanton: 1/2 way between Sonoma and Laguna Seca
Going out on a limb a bit.... I put the BMR tubular A arms a while back and have had no issues with them.... Have gone off into the dreaded tire wall and they still seem to be ok. If I remember right @Fabman has them as well? Way lighter thats for sure.
Yes, I have been rocking all BMR front suspension stuff including K member and Arms etc. for years and years. Despite the horror stories I have heard, I have personally only had one failure and it was the front sway bar/rad support that failed. A new improved part was developed and sent to me free by BMR. Everything else has been perfect....so far.
The 302s control arms are what most will recommend and are definitely suitable for this purpose, I just happen to have the BMR stuff and so far so good with it. I did punch the tall ball joints into them as the higher front roll center allows you to run a softer front spring which should improve bite from a lower roll center/higher spring package. Be aware though that a proper bump steer job will have to be performed with the tall ball joints.
 

Grant 302

basic and well known psychic
This is what I love about TMO. Technical questions can get posted and have several replies and no incorrect responses. :)

In my head, the tall ball joint + bumpsteer kit are akin or equivalent to a 'dropped spindle'. IOW, you can run essentially the same front end geometry, but 1/2" lower, if you change nothing else.

That said, I like this post the best:
I would recommend holding off on the taller ball joints for now. Install the coil overs and don't lower the front end of the car to the point that the front control arms are pointed up toward the spindle. This will keep your suspension geometry somewhat in tact. The added mechanical grip of the coil overs along with the wider tires could solve your issue. Driving technique plays a factor here as well. You want to limit the changes you do at one time to limit the required trouble shooting to correct an issue after the fact.
Here is a good read http://www.s197forum.com/threads/time-to-replace-ball-joints.96978/

Without other specific ride height/geometry/tire/spring setup info, I wouldn't recommend making the change for a street or dual purpose car. At least not yet. Since the OP is already changing to front coilovers, I'd just do that first, there will probably be enough to sort out after it's all (coilovers + bars) installed.

What springs are on the car now, and what rate springs are on the coilovers? What changes are planned for the front ride height?
 
5,152
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Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
This is what I love about TMO. Technical questions can get posted and have several replies and no incorrect responses. :)

In my head, the tall ball joint + bumpsteer kit are akin or equivalent to a 'dropped spindle'. IOW, you can run essentially the same front end geometry, but 1/2" lower, if you change nothing else.

That said, I like this post the best:


Without other specific ride height/geometry/tire/spring setup info, I wouldn't recommend making the change for a street or dual purpose car. At least not yet. Since the OP is already changing to front coilovers, I'd just do that first, there will probably be enough to sort out after it's all (coilovers + bars) installed.

What springs are on the car now, and what rate springs are on the coilovers? What changes are planned for the front ride height?
Agreed, and of all the myriad or folks who have installed the tall ball joints and bumpsteer kits...or just bump steer kits in general, I haven't met ONE who has set the bump properly.
Just as a reminder, here are the ACTUAL results I personally measured while doing mine.
First with the parts just thrown on and second with the bump corrected using an actual bump steer gauge-not just a guess by looking at the control arm angle and winging the adjustment.

This is what you get when you guess:
.240 out in only 2 1/2" of travel...that's 1/4" of an inch!


This is what you get when you do it properly:
.018 out in a full 3" of travel...that's only .006 per inch.


Which do you think would be more a stable/predictable car to drive?

As I always say, if you aren't going to do it right, don't do it at all.
The only possible result will be making it worse.
You may not realise it, but it definitely won't be right, unless you do it right.
My recommendation: Skip the tall ball joints and bump kit.

Okay, off my soapbox.
 
This is great! Thanks for all the input....very valid points. I bought the coilovers from a member and he thinks the front spring rate is 450 and the rears 225. Cortex chose the rates according to the previous owners needs which was a street/track car. I will be 90% track so I am not concerned about noise or harshness as much. Right now I am running the Ford P springs with no other changes. I will change the front bar to a 35mm adjustable and get shorter adj end links. As I mentioned with my previous post I just want to maximize front grip knowing that I have a rear bias. As for bump steer I planned on having Phoenix do the adjustment so I would hope they know how it's done right.
 

Grant 302

basic and well known psychic
If you're going to run at the P spring or higher geometry, then I don't think you need the balljoints/bumpsteer. Lower than that, and I'd consider it. What size street/track tires are you planning on using? Do you plan on changing ride height or camber settings at the track?

As far as all the bushings and NVH, I say start changing them out.
 
Will run 18x11 square with 305 slicks on track. Stock rubber on the street. I will have camber maxed out at the track....right now I get 2.7 but switching to MM plates that are pre-assembled with the coilovers. I honestly can't say I am that familiar with adjusting ride height, when to adjust, what level front to rear. This is the first coilover set-up I have ever run.
 

Grant 302

basic and well known psychic
If you're going to be running short slicks like 645s, then I think starting with the P spring front height or a bit higher would be a good starting point. Take fender arch or frame rail measurements at all four corners before you switch hardware. I'd go a little lower in the back, but it depends what LCA brackets you have and what adjustment point you plan to use.

I generally use a 2 position street/track approach for camber. 0º toe for the street with moderate camber like 1.5º to 1.8º and about 1/16" to 3/32" out total for the track with camber at max negative.
 

TymeSlayer

Tramps like us, Baby we were born to run...
3,765
2,666
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Brighton, Colorado
Have the BMR A-Arms, A-ARM support, K-member and radiator support up front as well and I like the weight savings. Haven't had any issues with any of my BMR stuff, including all the goodies in the rear.
 
A replacement K-member is on my budget "wish list" and then long tube headers will be right behind. I figure since you make the room you may as well take advantage of it
 

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