[vivekjayasheel]

I recently came across a thread by another member on here who had done some things to his NGCS to improve articulation. I thought that would be a great idea for a sticky post. Others can chip in too with their thoughts. It would be great to have all the information in one place. The Search function takes up the highest amount of bandwidth...

[dhanushs]

• Thar CRDe rear leaf springs.
• Fewer front leaf springs
• Shock Absorbers with more travel.
• Longer shackles and longer leaf perch will raise the body, and prevent interference of tyre and body

These are few things that you can do in stock form to make the Army version MM550 NCCS articulate more.

Further mods, may be going for coil spring, etc..

[GTO]

A recommended read : Related Thread

[sreejeshmp]

This is the max you can get from this set up .

Thar CRDe rear leaf springs.
Fewer front leaf springs (How much ? )
Longer shackles

This set up works well for me , and the credits goes to Sudarshan & Pratheesh.
- Sreejesh

[SPIKE ARRESTOR]

Originally Posted by sreejeshmp

Fewer front leaf springs (How much ? )
Longer shackles

Longer shackles - how long ?

This set up works well for me , and the credits goes to Sudarshan & Pratheesh.
- Sreejesh

Thanks Sreejesh, it is your generosity that you give credits. I have seen many so called "Jeepers" here who do not have this courtesy, despite offering them help when they are in need, that is why I have stopped giving free lunches these days. Being the one who prompted you to get a NGCS, I am happy to see you happy with your decision.

IMHO, the most credit must go to YOU, as you are the one who did all the trials and came out with an optimal solution. It is the execution that matters. I also think sometimes, you and Sudarshan , both are working in the wrong field (professionally), things mechanical come naturally to you (unlike those copy, compile, paste fellows) !

With your outcome, I know what my Jeep would look like.

Spike

[commander]

A perfect thread for the perfect time.

I have just completed a SPOA set up for my commander (pre ngcs) chassis and have been driving it for the last couple of days. Overall the jeep is stable on the highways and gives a consistent handling even on broken surfaces. One of the mods that I have added is a balancer rod to the rear leaf sets. What I have noticed is that:

* with the rear balancer rod driving on broken roads the rear jumps more. Without it its feels better on bad roads.
* the plus side is that the jeep is more stable at speeds around 60 on the turns which are mildly broken.

I hope you guys can help me understand better and if its an advisible thing to do. Sorry if its OT here. Will update my thread with details once my system is running.

[ex670c]

Originally Posted by commander

A perfect thread for the perfect time.

I have just completed a SPOA set up for my commander (pre ngcs) chassis and have been driving it for the last couple of days. Overall the jeep is stable on the highways and gives a consistent handling even on broken surfaces. One of the mods that I have added is a balancer rod to the rear leaf sets. What I have noticed is that:

* with the rear balancer rod driving on broken roads the rear jumps more. Without it its feels better on bad roads.
* the plus side is that the jeep is more stable at speeds around 60 on the turns which are mildly broken.

I hope you guys can help me understand better and if its an advisible thing to do. Sorry if its OT here. Will update my thread with details once my system is running.

Hi Palani,

The Rear Anti-Roll bar is a great addition.

To improve wheel travel with the anti-roll bar (Balance Rod) Please look in to the following.

1) Measure the Ground to front bumper height & Rear Bumper Height.
2) Remove the Anti-Roll Bar Linkage to the Leaf Spring Clamping Plate.
3) Again Measure the Ground to front bumper height & Rear Bumper Height.
4) Is there a difference?
5) Normally most anti-roll bars make the suspension squat down a few cms (inches). This in turn does not allow the suspension to travel its full range up or down.
6) You can make new Linkages with the above calculations and fit the anti- roll bar. ( This set up will be better off-road, and a moderate improvement on-road)

Do consider a Traction Bar to counter Axle Wrap in a SPOA setup.

Regards,

Arka

[Sudarshan]

Arka Ji you are confusing me .

What i believe is the anti roll / anti sway bar is for better road manners

But , for offroading it restricts the articulation.

Commander's vehicle seems to be converted to SPOA for better offroad manners (may be for good ramp angle). Now, How the addition of the said anti roll bar is going to be good for off roads ? I am missing something.

Sudarshan

PS. Interesting read >>
http://en.wikipedia.org/wiki/Sway_bar

[commander]

Originally Posted by ex670c

Hi Palani,

Do consider a Traction Bar to counter Axle Wrap in a SPOA setup.

Regards,

Arka

Hi Arka sir,
Just fell into a bit of an issue before i could do the traction bar. Hope to get it sorted by this weekend and will update soon. Will try to post some pics of the wheel travel and articulation if possible too.

Thanks.

[ex670c]

Originally Posted by Sudarshan

Arka Ji you are confusing me .

What i believe is the anti roll / anti sway bar is for better road manners

But , for offroading it restricts the articulation.

Commander's vehicle seems to be converted to SPOA for better offroad manners (may be for good ramp angle). Now, How the addition of the said anti roll bar is going to be good for off roads ? I am missing something.

http://en.wikipedia.org/wiki/Sway_bar

Hi Sudarshanji,

My understanding is the Anti-Roll bar in a SPOA vehicle can be used to restrict the articulation.

In JEEPs with a C-Section Chassis, the Chassis Flexes with the Suspension, this causes a very unpredictable behaviour in SPOA vehicles.

This is further aggravated, by the fact the relocation of the Axle and wheels in SPOA, changes the way leaf springs are supposed to function.

The Compression/Jounce and Rebound characteristics, change, this forces the chassis to flex more and when it cannot the vehicle tips or rolls, coupled with a 4-5" higher Centre of Gravity.

An Off-road specific -Anti-Roll Bar/Sway Bar will be useful.

http://www.youtube.com/watch?v=VvOCtXtGUHQ

http://www.youtube.com/watch?v=t3N73TJc7xU

Regards,

Arka

[ringoism]

Originally Posted by ex670c

Hi Palani,

The Rear Anti-Roll bar is a great addition.

To improve wheel travel with the anti-roll bar (Balance Rod) Please look in to the following.

5) Normally most anti-roll bars make the suspension squat down a few cms (inches). This in turn does not allow the suspension to travel its full range up or down.

Arka

Well, you can take the following as a compliment, Arka - in that, until now, everything I've seen you write / reply was AFAIK completely correct. Your knowledge of Jeeps is incredible and I've personally benefited numerous times while perusing so many threads you've contributed to.

But let me assure you and anyone else reading that anti-roll bars do NOT (and cannot) make any suspension squat down, or up, or any other direction. There is absolutely no possibility, from a technical or practical standpoint, of such a thing happening. What anti-roll bars (or "sway bars") DO is exactly what the name suggests, and as Commander rightly understood - they prevent roll / sway / A.K.A. articulation.

On road-going high-performance vehicles, you want the vehicle to remain flat as possible to enhance control and limit body roll / weight transfer towards the outside of the turn. In such a scenario, each end of a sway bar acts as a lever, with the length of bar in between transmitting this leverage via torsional force to the lever on the opposite side, so that it moves in the same direction; thus when body weight shifts to the outside of a turn (for example, to the right side on a hard left turn), suspension height remains similar from side to side, because as the right-side springs deflect and the suspension moves upward, the left side springs will be forced to do approximately the same. Exactly how similar the height is forced to remain depends on the weight / speed of the vehicle, the radius of the turn, and of course, the DIAMETER of the bar (larger diameter = more torsional force on opposite side lever = more similar amount of movement = less lean / flatter body through a corner, while smaller bar = less torsional force acting on opposite lever = more difference in suspension deflection from side to side = more body roll.

Commander rightly observed the typical effects of adding one: it will seem "choppier" in rough turns (or even on a rough straight at low speed). Perfectly logical - think it through: You have a fairly compliant suspension, and hit a low spot in the pavement on the right side. The right side sway-bar "lever" is forced suddenly downward as that wheel drops into that low spot, thereby transmitting a torsional force through the bar to the left side, which is also forced downward - except, there's no depression in the pavement on the right side!!!! So what happens? The left side suspension moves down, but it's on a flat road; since the suspension cannot move DOWN on the left (it's up against immovable pavement!), instead the chassis / body are forced UPWARDS - so the body pitches to the right! Have this happen on a hundred little ripples on a rough high-speed turn at speed, and of course, the ride will feel a little choppier with many tiny side-to-side movements in the body - but you'll still corner a lot flatter (less body roll), since the suspension is being forced to remain at an essentially similar level from side to side.

For a high-performance off-road vehicle, you kind on want the opposite of what you want on-road. You're not taking turns at high speeds, so body-roll in that sense is not an issue. And much of the time, you're faced with situations where one side of the vehicle is traversing terrain totally different from the other side, and since you want each tire to be doing as much as possible towards moving the vehicle forward, you actually do NOT want the suspension on one side to be affecting the other side at all (ideally). Thus an anti-roll bar is generally going to be counter-productive, since "affecting the other side" is exactly what it's designed to do.

I've heard of one high-end SUV (Land-Rover, I think) that had anti-roll bars that could automatically disconnect at the touch of a button, for times when one ventured off-road. Since most of these high-end sorts spend 90+ % of their time on-road, this is a valuable feature.

For the rest of us with low-end, low-tech Jeeps, etc, best thing is to apply and size anti-roll bars corresponding to intended use. If we do only OTR, then omit them entirely, and gain considerably better articulation. If we drive a mix of off/on road, keep a front one of moderate size (which is exactly what the factory has done, knowing that most customers drive a mix), and you'll get fairly acceptable (though necessarily compromised) performance for either. If we're mainly on-road, then size up the front one (Bolero 1-ton Pik-up for NGCS-width axles, etc), and maybe even add a rear one from a Safari or whatever. The vehicle will be a lot more stable in turns at speed.

Being that I owned only road-going high-performance vehicles before moving to India and buying the 4x4 Marshal, and that I built-up / modified many of them, and also competed in slalom-racing events, I've had quite a lot of experience with anti-roll bars and the effects of adding them / increasing their diameters (even using polyurethane bushes vs. rubber on mounts / end-links), etc.

Hope this wasn't all too opaque... this is really what they do / don't do. Check wikipedia or whatever if you want a second opinion.

-Eric

[sreejeshmp]

improvement in articulation.

[jeepbug]

I got longer shackles and poly urethane bushes I feel now the body roll is more evident and vehicle is less stable in the fast turns


Sent from my iPhone using Team-BHP

[ringoism]

Our Marshal (NGCS) is a little short on articulation, so found this interesting. In our case, too many springs in the packs up front (rears reduced already, but re-arching didn't hold up very well, I suppose some re-heat-treating is required). Exactly how long (bolt-to-bolt center) are your shackles as pictured?

Little OT, but out of curiosity, what are those tires fitted in the photos? Look like the export MRF units I saw somewhere (but how to source them on the subcontinent???) How's the performance?

Originally Posted by sreejeshmp

Attachment 1133273


This is the max you can get from this set up .

Thar CRDe rear leaf springs.
Fewer front leaf springs (How much ? )
Longer shackles

This set up works well for me , and the credits goes to Sudarshan & Pratheesh.
- Sreejesh

[lifeoffroad]

Originally Posted by sreejeshmp

Attachment 1226352
improvement in articulation.

Hi Sreejeshmp,

My apologies for bumping an old thread but I love what you have done with your NGCS MM550 in terms of Articulation and would love to get some guidance from you to try and get mine behave a bit better in this regards.

Mine is a 2004 550 with a SZ2600. I currently have bolero leaf springs and some longer shackles.

Here are my questions for you:

Would Boomerang Shackles help?
What leafs would be better for articulation?

Anything else you may recommend?


Thanks in Advance.

Regards,
L.o.R