Max. Flex vs. Useful Flex and The Anti-rock - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep Wrangler Forums > TJ Wrangler Technical Forum > Max. Flex vs. Useful Flex and The Anti-rock

Introducing MONSTALINER™ UV Permanent DIY Roll On Bed LineWe have Engo 10k Synthetic IN STOCK!!! Hurry while supplieJeep speedometer gears at rockridge4wd

Reply
Unread 01-21-2005, 02:41 PM   #1
lupinsea
Registered User
2001 TJ Wrangler 
 
Join Date: Jun 2004
Location: Kenmore, WA
Posts: 3,586
Max. Flex vs. Useful Flex and The Anti-rock

Maximum Articulation, Useful Flex,
and the Curri Anti-rock

By Lupinsea



Image from rockcrawler.com with Anti-rock installed


Often in discussions and various threads here on Jeepforum.com there are quesions of a good swaybar disconnect system or methods to develop the maximum flexibility out of the TJ's suspension system. Invariably, someone in these threads will mention the Anti-rock offroad swaybar which is then followed by questions about what is it, how does it work, and which develops "more flex." This post is an attempt to explain the idea that there is a difference between "Maximum Articulation" and "Useful Flex" as it pertains to offroad situations and how this relates to the Anti-rock and typical quick-disconnect systems.

I will tell you right off the bat that you will develop more "maximum flex" with any of the quick disconnets than you will with the Anti-rock. But how useful will that maximum flex be? Bear with me . . .

Maximum Articulation
There are some Jeepers that hold the contention that all flex is not created equal. That there is "maximum flex" and there is "useful flex." Maximum flex or articulation is just what it sounds like. Just how much you can completely flex out your particular suspension setup. Max flex will give great RTI numbers and really great pix of Jeeps with tires high in the air and people will say "holy snot, look at that." The quick disconnects are great with developing maximum flex since they completely disconnect the swaybar from the axle.


Impressive, but how much effective force is on
the tire if the spring unseats from the perch?

Sometimes you'll see pictures of Jeeps so flexed out that the springs actually have no load on them and in fact may drop down from the upper spring perch. This is were we get into the idea of "useful flex." When a tire can droop so much that the spring unseats there isn't much weight on the tire. Without the weight there won't be much taction from the drooped tire. In this situation one has to ask what is the practical difference between this and having a tire lifted in the air from a traction stand point?

Useful Flex
So the idea of "useful flex" is introduced. And that is the point at which you can flex out and still get power down to the ground with enough traction. Unfortunately, this is much more difficult to pinpoint because it will depend on many factors such as ground surface conditions, tires, traction aiding devices, specific suspension setup, load distribution, and perhaps other factors. John Currie, who's won many rock-crawling competitions and has a good reputation with the community for thoughtful designs and solutions, approaches the flex issue from the "useful flex" stand point with the Anti-rock.

Anti-rock
The Anti-rock is an anti-swaybar specifically design for off-road driving and offroad conditions. Currie carefully engineered the swaybar to balance flexibility with chassis control. It works with the rear swaybar and keeps both front and rear swaybars connected at all times to evenly distribute forces between the front and rear axles aiding traction by keeping the weight on the tires. While much softer than the stock bar the Anti-rock also helps control body sway and lean off-road making side-slope and off-camber situations much less trecherous to negotiate.

I was surprised at the difference in off-road ride after the Anti-rock installation. The Tj felt like it just melted over the terrain. When I'd approach holes, ruts, and drop offs I would expect the TJ to shift and sway toward the depression. Not so. The tire would drop into the hole in a controled way and the chassis remained surprisingly level, balanced between front and rear axles. And the traction difference is noticable, too, especially since I have open diff's at each end. I met guys on the trail who said "oh you'll definitely need a locker to get up that hill, if you have problems, just wait for us." But the TJ would just scramble right up with no hint of any traction problems.


Image from rockcrawler.com showing the Anti-rock in action.

Besides the handling benefits there is also the ease of use. Once the Anti-rock is set up you just leave it alone. The only reason to stop at the trail head is to air-down tires. . . otherwise just roll onto the trail and roll off. No pulling pins or tying the swaybar out of the way. Likewise, when you're coming off the trail you don't have to get under a muddy Jeep and hook things back up in the rain and muck or whatever you just wheeled through. No rocking the Jeep back and forth to line-up pin holes or anything. It simply works very transparently and you forget it's on there.


Click to enlarge: The Anti-rock
installed on author's BB lifted TJ.
No pins to realign or discos
to fuss with

Despite the added control, the Anti-rock does allow a surprising amount of articulation. In one rockcrawler.com article the author quantifies the difference between fully disconnecting the swaybar and running the Anti-rock:
  • 33.25" fully disconnected (20* RTI = 1050)
  • 32.00" loosest Anti-rock setting (20* RTI = 1011)
  • 31.25" firmest Anti-rock setting (20* RTI = 987)
As you can see, the "maximum articulation" is developed by fully disco'ing the swaybar but the Anti-rock still allows for significant flex while providing the handling benefits. Even at the firmest setting the you only give up 6% of your total flex for all the benefit. And at the looses setting? Less than 4%

The Anti-rock isn't cheap at nearly $300. However, if anyone is considering the $100 JKS or Teraflex quick discos then they owe it to themselves to look into the Anti-rock. Honestly, after runnning with this mod for the last 6 months I would highly recommend it to anyone as it's one of my favorite mods. Especially since you can keep it with your TJ if you upgrade suspension systems and axles.

Additional Resources

Review & Install on a 2" BB Lifted TJ
General Anti-rock Review & Install Pictures
Another Installation Review
Even Stu Olsen Installed One
Rockcrawler.com Reviews the Anti-rock Before/after articulation measurements at end of article

.


__________________
- Jay
lupinsea is offline   Reply With Quote Quick reply to this message
Unread 01-21-2005, 02:49 PM   #2
bigjohnwhodatis
Registered User
 
Join Date: Nov 2003
Location: The Nasty 'Nati
Posts: 328
Great write-up! My only concern with the AR is the on-road handling, how is it?
__________________
2" RE BB/Tera 3" Front Coils
1"BL/MML
33x12.5 Dunlop Radial Mud Rovers
Warn M8000
Jeeperman Rock Sliders
Big dreams and a little wallet
bigjohnwhodatis is offline   Reply With Quote Quick reply to this message
Unread 01-21-2005, 03:46 PM   #3
AudioGuru
Registered User
 
Join Date: Apr 2003
Location: || <--This close to being banned.
Posts: 783
Great write up, and I agree that an Anti-Rock is superior to quick disconnects.

However, the next time you see a TJ flexed so far that a spring is loose, have the driver stop and you go try to lift the drooping tire. Preferably do this with a hook and a hanging scale, so that you can see how much force is being exerted downward by that tire. You'll be surprised. Remember since both springs are inboard of the tires, by having the right front tire stuffed, the right spring will push down on the left front tire, even though the left spring isn't exerting any downward force.

But yes, anti-rocks are sweet and quite a bit more pricy than a disco system.
__________________
[URL=http://www.villagephotos.com/pubbrowse.asp?selected=826692][B]Electric Hardtop Hoist[/B][/URL]
[URL=http://www.clifford.com/matrix/responder/default.asp][B]Clifford Matrix[/B][/URL]

[COLOR=White]Don't lie. God said so.[/COLOR]
AudioGuru is offline   Reply With Quote Quick reply to this message
Unread 01-21-2005, 07:09 PM   #4
Jerry Bransford
Administrator
 
Jerry Bransford's Avatar
2004 TJ Wrangler 
 
Join Date: Jan 2003
Location: Escondido, California, California
Posts: 60,632
I asked Jay (Lupinsea) to post the above information here that he had written earlier in another thread so I could make it a 'sticky'. Thank you very much Jay for taking the time to make such a well written contribution to the Forum. I hope everyone enjoys it and can put his nicely written information to good use.
__________________
Getting Savvy...

Coolest offroad magazine ever! CRAWL Magazine

When you have a choice, buy American.
Jerry Bransford is offline   Reply With Quote Quick reply to this message
Unread 01-22-2005, 06:36 PM   #5
NetJunkie
Registered User
 
Join Date: Feb 2004
Posts: 370
For those looking at the Anti-Rock also check out the Sway-Loc from www.offroadonly.com. It costs more, but utilizes two seperate sway bars for onroad and offroad.
NetJunkie is offline   Reply With Quote Quick reply to this message
Unread 01-27-2005, 03:10 PM   #6
Jerry Bransford
Administrator
 
Jerry Bransford's Avatar
2004 TJ Wrangler 
 
Join Date: Jan 2003
Location: Escondido, California, California
Posts: 60,632
Quote:
Originally Posted by NetJunkie
For those looking at the Anti-Rock also check out the Sway-Loc from www.offroadonly.com. It costs more, but utilizes two seperate sway bars for onroad and offroad.
Yeah that looks to be a really good device, lots of my technically astute buddies are really impressed with it. The Sway-Loc work like an Antirock offroad but it adds a second street setting that has the stiffness of the OE antiswaybar. Heck I might even try to figure out how to sell my Antirock and get one of those for my own Jeep.
__________________
Getting Savvy...

Coolest offroad magazine ever! CRAWL Magazine

When you have a choice, buy American.
Jerry Bransford is offline   Reply With Quote Quick reply to this message
Unread 01-27-2005, 03:28 PM   #7
redrockyj
Registered User
 
Join Date: Apr 2004
Location: SLC, Utah
Posts: 104
how much for your antirock jerry? if you do decide to sell it i might be able to buy it off you when my next paycheck comes around as long as its in decent condition.
redrockyj is offline   Reply With Quote Quick reply to this message
Unread 01-30-2005, 09:43 PM   #8
ErikJordan
Pimp Hand
 
ErikJordan's Avatar
1995 YJ Wrangler 
 
Join Date: Apr 2002
Location: Lakewood CA
Posts: 5,088
the sway-loc is a fantastic design. the ability to switch back and forth from the anti-rock looseness to the rigidity of the street driving mode is a fantastic concept. from what i understand, and have seen, there are a few minor bugs to work oit on it, but when they are resolved, this will be a must have for off roading tj drivers
__________________
___________________________________________


What is all of this talk of Savvily designed products?
ErikJordan is offline   Reply With Quote Quick reply to this message
Unread 02-10-2005, 11:57 PM   #9
slimP
Senior Member
1999 TJ Wrangler 
 
Join Date: Apr 2002
Location: Louisiana
Posts: 676
Great write-up, thanks
__________________
--==('99 Tj Sport - In progress)==--
--==(Blue Jeep Club Member #11)==--
--==(Pride, Heritage, Tradition - The American Legend - JEEP)==--
slimP is offline   Reply With Quote Quick reply to this message
Unread 05-08-2005, 11:56 PM   #10
?????
Registered User
 
Join Date: May 2005
Posts: 126
I'll add my 2 cents.

The antirock will 'slightly' limit an RTI score, but in a real world situation, it does not limit flex at all. With the antirock installed I still max out my OME LT shocks, but it offers more resistance throughout the travel and makes it much more stable.

To test it out, I once disconnected the bottom mount of my shock and flexed through a rut with diagonally opposing tires drooping. With the antirock installed on the loosest setting my OME LT shock was completely maxed out and then had atleast 6" between the bottom of the shock, and the shock mount on the axle. Even at that I was still limited by the size of the rut, I believe it could have drooped another 6" before the antirock arm and link would have been straight.
????? is offline   Reply With Quote Quick reply to this message
Unread 08-10-2005, 09:47 PM   #11
RedSyphon
Registered User
 
Join Date: Jun 2005
Location: Gainesville, FL
Posts: 115
does anyone out there know the performance decreese/compromise for a DD that the Currie anti-rock would cause?

Atm I take corners like a mad man Even scare my friends who drive lower riding cars for the hell of it.

But in ther VERY near future (in fact the lift is already on teh truck ) I will be getting a OME 2.5" w/ a 1" MML & BL.

So I realize I am going to have to take the corners easier as is, altho I am still looking for the option to swerv around say... a crazy suicidal armadillo stuned in my lights

Thanks
RedSyphon is offline   Reply With Quote Quick reply to this message
Unread 08-10-2005, 10:31 PM   #12
wil badger
Registered User
 
Join Date: May 2005
Location: Utah
Posts: 2,895
as much as i don't like the company have any of you seen this

TeraFlex S/T swaybar
__________________
One Built XJ
wil badger is offline   Reply With Quote Quick reply to this message
Unread 08-11-2005, 07:08 AM   #13
RedSyphon
Registered User
 
Join Date: Jun 2005
Location: Gainesville, FL
Posts: 115
hmmm, i wonder how well it lasts..
seems almost TOO simple to me...
just being abelt o twist a knob and be off that is
RedSyphon is offline   Reply With Quote Quick reply to this message
Unread 08-17-2005, 09:10 AM   #14
NetJunkie
Registered User
 
Join Date: Feb 2004
Posts: 370
Quote:
Originally Posted by wil badger
as much as i don't like the company have any of you seen this

TeraFlex S/T swaybar
The Tera system is a fancy disconnect. It's not like a SwayLoc in that you have an off-road bar. You are either connected or not with it.
__________________
'04 Rubicon | Nth Degree 4.5" LA | ORO SwayLoc | ORO U-Turn Steering | 33x12.5x15 MTRs | 15x8 Streetlock Rims | AEV Rockers | ARB Winch Bumper | Warn XD9000i | Offroad-Technology Rear Bumper
NetJunkie is offline   Reply With Quote Quick reply to this message
Unread 08-17-2005, 09:43 AM   #15
wil badger
Registered User
 
Join Date: May 2005
Location: Utah
Posts: 2,895
never said it was .just putting it out there .one more to have discos with out having to get under the truck to do it.i wouldn't use it.i just take my swaybars off and throw them in the trash
__________________
One Built XJ
wil badger is offline   Reply With Quote Quick reply to this message
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.
Note: All free e-mails have been banned due to mis-use. (Yahoo, Gmail, Hotmail, etc.)
Don't have a non-free e-mail address? Click here for a solution: Manual Account Creation
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.


Thread Tools


Suggested Threads





Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.