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Old 11th December 2009, 00:50   #136
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@Samurai - I wouldn't trust any product that advertises "Excellent vehicle stability while breaking at high speed."

OT - Are these available for Amby's and Padmini's by any chance ?
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Old 11th December 2009, 06:56   #137
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To each his own of course, and my view is that it is not worth the bother and the possible risk/deterioration of handling for the Gypsy front end, in a car in which I sometimes touch 80/90 on good surfaced winding roads. What the car needs is for the rear to be tamed, the front is not a big contributor to the bucking bronco ride of the car. Which can of course be achieved just as well by loading up the rear, but the CFLs may offer a better alternative. Now to wake up the owner and get him to respond!

Last edited by Sawyer : 11th December 2009 at 06:59.
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Old 11th December 2009, 08:19   #138
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Originally Posted by rjstyles69 View Post
Thanks for letting me know Sharath.
You asked for it. I knew you would know your Scorpio doesn't have leaf. Yet, by posting such a question in this thread, you asked for it.

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Originally Posted by rjstyles69 View Post
However I really would like to know what needs to be done to keep this monster on road during those high speed sprints.
Isn't that the eternal question? How to deal with dancing suspension of Scorpio. I have been hearing this question ever since I joined Team-BHP, but never heard any solutions to that. In fact, I was on the receiving end once: https://www.team-bhp.com/forum/90759-post33.html

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@Samurai - I wouldn't trust any product that advertises "Excellent vehicle stability while breaking at high speed."
Being from a product company I can tell you this. Brochures are written by copy righters who are generally not technical. If a word passes through the spell-check, they wouldn't bother further. Also, brochures are not passed back to the engineers for proof-reading before they are given to the customers. Because engineers tend to nit-pick on every line. It is quite common for engineers to find embarassing mistakes in the brochures later. Therefore, don't judge the product to be good or bad by nitpicking on the brochures or websites.

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OT - Are these available for Amby's and Padmini's by any chance ?
I don't know, you better check with the company.

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To each his own of course, and my view is that it is not worth the bother and the possible risk/deterioration of handling for the Gypsy front end, in a car in which I sometimes touch 80/90 on good surfaced winding roads. What the car needs is for the rear to be tamed, the front is not a big contributor to the bucking bronco ride of the car.
Even I am not inclined to use it in the front side. My main problem area is the ride at at the back. So far it hasn't improved much. Today I am giving the jeep for making a new shackle bush.
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Old 11th December 2009, 09:23   #139
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You can find some of them in this thread itself, if you read from the start.
Hi,
Actually I did. Must have missed something.

Except for one graph (which shows that the CLF is softer), did not find anything technical to justify changing over.

My attitude: Would love for it to work, but as of now, I'm cynical. But with an open mind.

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Old 11th December 2009, 10:59   #140
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You asked for it. I knew you would know your Scorpio doesn't have leaf. Yet, by posting such a question in this thread, you asked for it.
Well I admit I never took a peek below to check whats beneath and never even popped a single page in the manual.I was checking the CF leaf springs video with the testing done on the Endy and posted right away.
Honestly I find the diesel's a tad bit cumbersome to understand unlike the petrols.
The million $ question still remains, how to keep this monster on road.
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Old 11th December 2009, 11:12   #141
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The million $ question still remains, how to keep this monster on road.
Having read about the Scorpio handling issues, I always give them a wide berth when I see them running at 120 on the open roads and e ways. Reading this tells me to give them an even wider berth henceforth! I have always wondered how the drivers don't seem to have a care in the world when they race around the way some of them do in it. Lack of imagination combined with blissful ignorance I suspect. I also suspect that the Tata SUVs are not much better.
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Old 11th December 2009, 12:57   #142
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Originally Posted by Sutripta View Post
Hi,
Actually I did. Must have missed something.

Except for one graph (which shows that the CLF is softer), did not find anything technical to justify changing over.
I found one more document, not sure whether it is posted here. I've attached it.

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My attitude: Would love for it to work, but as of now, I'm cynical. But with an open mind.
I didn't go for it blindly. I saw it working on Shahnawaz and Viji's vehicles and they were very impressed with the improvement in ride. Now they are trying out the front leaf, but that hasn't work out well, so far.

It has been two months since this installation. I have not seen any dramatic improvement so far to justify the huge price I paid. With MRP of 20K for the CJ340 rear CF leafs, it has to make dramatic improvement in ride quality. But I am talking pre-maturely since the installation has been far from perfect, for being the guinea pig I have to do quite some experimentation. I did get a small discount in price for being the guinea pig though.

However, there is light at the end of the tunnel. Today I visited a master mechanic in Udupi to resolve the problem in fitting the CF leaf properly. When I went there, the plan was to make a custom shackle bush to relieve the pinching by the shackle plates. However, star_aqua's suggestion of using a grease shackle kit was still lingering in my mind. The Mahindra workshop had ruled out the possibility saying grease tyre shackle kit is not available for bumper end of the leaf springs. Apparently it is not an OE design, so Mahindra workshop won't deviate from it.

Today I brought up the same issue with the master Mechanic. He said it should be possible, but he wanted to see the existing shackle bush before commenting. After all, he has never seen a CF leaf before this. So we jacked up the vehicle, and removed the leaf end and the shackle bush. It was the exact size as the grease type shackle kit. I just wanted to break into a dance right away...

So we quickly went to a local auto shop and bought 4 shackle assembly kit. I stayed around to see one of them being fitted. It fits gloriously, and now the CF leaf is able to move very freely, without any hitch. Then I came back, the Jeep has some work needed to be done, I'll get it back tomorrow evening. Only then I will be able to see the real effect of CF leafs on the ride comfort of my Jeep.

Last edited by Samurai : 11th December 2009 at 13:00.
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Old 11th December 2009, 14:23   #143
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I found one more document, not sure whether it is posted here. I've attached it.
Hi,
Thanks for the attachment. Yes, this graph is reproduced in one of the posts, and is the one I'd referred to.

Let me play the Devil's advocate.

a) I think a softer spring than standard (whether steel or composite) would give the same results as shown in the graph.

b) A monoleaf will be better at filtering out small bump harshness, as it does not have the friction (stiction) of a stack.

c) Until and unless it is a rising rate spring, I don't see how it can offer any improvement, other than that mentioned in point b.

d) The characteristics of light weight, higher elastic limits, much higher fatigue life etc. are difficult to use to advantage in a drop in environment.

To elaborate these one by one.

Light weight: True. But effect on overall vehicle weight is likely to be negligible. There is going to be a more pronounced change in the suspended/ unsuspended mass ratio, in favour of the CLF, but whether it has any significance can only be ascertained by measurements and calculations. Also, if it is significant, damping parameters need to be changed.

Much higher fatigue life: True, if properly made. But how does it affect the point in question i.e. ride and handling.

Ability to withstand much higher deformation without permanent damage/ failure: True, if properly made. This is the tricky part. This is a property which cannot really be exploited easily. It can be used to increase suspension travel. But in a drop in environment, suspension travel will be limited by your bumpstops and shocker length. Also, in a cart sprung system, the spring also locates the axle, and there are other limits to how much travel the axle can have.

Nowhere in the literature is it mentioned that it is a rising rate spring. But it seems to be implied. Which is why I asked if anyone has measured it.

When a vehicle leaves a factory, it is designed/ built for the worst case scenario. In this case maximum load, even overload. If you know that you are not going to operate in that part of the operating region, you can always optimize it for the part you are going to operate in. It is just that I don't think it needs CLFs in this case.

Lots more to add, if need be, but this will do for now, I think.

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Old 11th December 2009, 15:32   #144
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Hi,
What reason does the manufacturer give for not recommending it for front axle use?

Regards
Sutripta
see the g-values on the test page. What i understood- the CFL composite is more flexible.This lack in Lateral stiffness affects handling
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Old 12th December 2009, 07:06   #145
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see the g-values on the test page. What i understood- the CFL composite is more flexible.This lack in Lateral stiffness affects handling
Hi,
The CFL is softer. In the z axis. You can make a softer steel spring also. What happens in a orthogonal direction is another matter altogether. Would like to have the MANUFACTURERS comments.

If anyone has discussed this with the manufacturer, please post.

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Old 12th December 2009, 07:31   #146
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My take on this is that if this is the next best thing since sliced bread where the Gypsy is concerned as some here seem to think, Maruti should incorporate this to tame the rear end, because anything which does this to the extent claimed is a godsend for the vehicle. But Maruti has zero interest in doing anything new for the Gypsy - an aside, I wonder what they plan to do to keep the car emission compliant from April - so maybe some of the other makes may take this up if they see any sense in it.
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Old 12th December 2009, 07:55   #147
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Carry deadweight in your Gypsy! Know a few people who do this.

Sutripta
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Old 12th December 2009, 08:59   #148
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My take on this is that if this is the next best thing since sliced bread where the Gypsy is concerned as some here seem to think, Maruti should incorporate this to tame the rear end, because anything which does this to the extent claimed is a godsend for the vehicle.
I think the gypsy has a beautiful suspension setup and any tweaks will affect the handling



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Carry deadweight in your Gypsy! Know a few people who do this.

Sutripta
Good and smart suggestion - i have done this for highway driving and found the vehicle to handle better!
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Old 16th December 2009, 23:30   #149
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Ok, after 10 weeks of brain-storming with various people, I finally installed the CF leafs the way it should be installed. Since mine was the very first SWB Jeep to get CF leafs, it was not an easy procedure.

Just before CF installation, wrong shocks (from Bolero Pickup) were installed in my Jeep since the Mahindra workshop didn't know the correct part number. After few weeks of super bumpy ride, the workshop replaced the shocks with the right one.

Initially I was told that OE U-clamps and shackles can be used with the CF leafs. But that was not true. After some brain-storming with few guys, I settled for the 6 inch U-clamp instead of the OE 7 inch U-clamp. That fit very well, and the CF leafs got installed.

However, I could barely notice the improvement in ride. In addition, I started getting a grunting sound whenever the Jeep jerked forward or backward. The workshop identified the problem as coming from the shackle which was holding the leaf very tight. Therefore the leafs were not flexing freely. This problem took the longest to solve. I didn't want to try too many things. So I got many ideas from different Jeepers and considered each of them. Finally the grease type shackle kit solved the problem.



OK, there is a big improvement in ride quality. Today my wife took a ride and noticed considerable improvement in ride comfort. So, it works!

It is worth 20K? I am not so sure. It depends on how much you value ride comfort in a Jeep.
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Old 18th December 2009, 07:59   #150
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Hi,
Any chance of measuring the spring rates for the stack, and the CFL for the CJ3B?

Regards
Sutripta
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