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Old 20th April 2010, 18:30   #31
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Originally Posted by mooza View Post
On the other hand, stiffer shocks, of the stock length itself (Bilsteins B6, for example), may have prevented the bottoming related to shortened coils. It would have been interesting to see the results of the combination of the shortened 12.5 inch springs with stiffer shocks. May be you could try this on your 4th Scorpio, when it comes
Mooza a quick review of the bilsteins would actually be a thoughtful idea. Definitely would help quite a few owners on the forum.
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Old 20th April 2010, 19:52   #32
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@rjstyles69 and other friends, I have so far logged around 2000 kms with the Bilsteins B6 shocks, on my leaf spring Scorpio. I have posted my experience in the thread below :

http://www.team-bhp.com/forum/modifi...pension-2.html (Upgrade options for Scorpio's suspension ?)

I will be glad to answer any specific questions regarding the mod
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Old 20th April 2010, 22:42   #33
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Hey Immortal, I think he's done it only for the rear so alignment should be OK there (solid axle) but its going to have a squatted stance.
Immortal? Who? And Why?

Sutripta
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Old 20th April 2010, 22:59   #34
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Originally Posted by hps aulakh View Post
@ everyone who been thinking that this experiment was undertaken without going in the tech details and being a novice.I happen to be a vintage & classic car collector for the past 15 years with a collection of about 32 cars and been a dealer for mahindra and escorts for about 23 years ,so i know the way their R&D dept. functions.
Not being too much of a critic, i fail to understand the purpose of this thread.

What has restoration of a Vintage and a classic car got to do with reducing the body roll of a Scorpio.

When Mahindra's cant stop the rocking cradle in all these years. You tried, but various other issues cropped up, there is no possibility in your experiment being successful.

What we can conclude here....?

What mooza says has lot of logic.

Last edited by PAVAN KADAM : 20th April 2010 at 23:01.
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Old 21st April 2010, 01:28   #35
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Here you go. Original msg below
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Originally Posted by Sutripta View Post
Immortal? Who? And Why?

Sutripta
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Originally Posted by ImmortalZ View Post
Cut the coil springs eh? Nice idea. Did you ever pause to think about the consequences?

Now your dampers have lost 2.5inches of travel. Your spring rates have changed. Your ride height has changed.

Your shocks will blow soon, your handling will be in the pits and your tire life will shorten heavily because the geometry has changed (camber will be off, toe and caster need to be checked to be sure) and your vehicle has lost some if not all off roadability and God knows what happens when you bottom out your suspension. The dampers, springs, stock sway/anti-roll bars (if any) are all matched together. If you're doing something as crude as cutting off coils (are stock springs linear or progressive?), you've just ruined the suspension setup.

What you should've actually done is researched rear sway bars. Or gotten the Bilstein suspension kit for the Scorpio.
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Old 21st April 2010, 22:19   #36
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Quote:
Originally Posted by Mpower View Post
Here you go. Original msg below
Oops. Read in more than warranted.

Sutripta
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Old 29th June 2010, 01:51   #37
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I understand that hps aulakh has changed his car but I still thought this was worth discussing.

Quote:
Basically your shock piston is working as a jounce stop and once to hit a huge bump it will destroy the shock. What you need is a smaller shock or move the shock top mount further up or move the bottom mount further down so that the piston travel is correct.
@Mpower: I have to disagree with you here. Here are my reasons. Only the spring length has been changed. The position of the axle in full jounce/compression is limited by the bump stop plate. The linkage geometry has not been changed. Therefore, irrespective of the spring rate, the final position of the axle in full jounce position is not altered. And the damper should already be designed taking into account the full jounce position. Therefore this alteration should not make the damper bottom out.

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The negative point was that as the shocker length was reduced from 14 inches to 12.5 inches it used to bottom on a jump. As no 13 inch shocker was available in the market i had to replace the cut coil springs.
As I said earlier the final position of the axle when the spring is fully compressed has not changed. Therefore, irrespective of the initial length of the spring and damper, the final lengths in full compression are still the same because they are limited by bump stops that determine their final position. So it means that your shock will not bottom out, unless of course it wasn't designed properly (i.e. taking into account the full jounce position) in the first place. So in my opinion, the idea of putting shorter dampers is redundant.

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The shockers used to bottom only in a big pothole or on real bad roads.
How did you find this out? Some kind of audible sound? What I say is happening is that the total load bearing capacity of your rear springs has reduced (and there is lesser travel too) which makes it bottom out more often. Hence, the axle is frequently hitting the bump stop hard which is creating the sound.

Otherwise, by cutting off a coil, the spring has become stiffer, not softer. It's also reduced the ride height at the rear and hence the centre of gravity a bit too (and the car should have a permanent tilt to the rear now compared to in stock condition), so you're left with a car that rolls less in corners. But yes, that change in spring stiffness has a whole host of associated impacts. Just reverse the process, put new stock springs at the rear. Problem solved, that's of course assuming that the dampers are not very old and still have life in them. And I forgot, I think the Scorpio springs are in fact conical (a small angle), so cutting off a coil at the top or bottom will have different impacts.
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Old 29th June 2010, 08:15   #38
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Originally Posted by Motorholic View Post

1. What I say is happening is that the total load bearing capacity of your rear springs has reduced

2. Otherwise, by cutting off a coil, the spring has become stiffer,

3. Just reverse the process, put new stock springs at the rear. Problem solved

1. Load bearing capacity of a spring does not get affected by cutting off coils, since each coil element sees the full load.

2. Yes, I do agree the spring does get stiffer when you cut off coils.

I do not know if Hps aulakh had changed the bump stop settings as well, to accomodate the reduced spring length, though this would have been risky, considering the risk of reduced wheel clearances with respect to the underbody. Maybe he can answer this. Assuming he didn't, your analysis on the bottoming out looks correct

3. It looks like Hps aulakh undid this mod anyway before selling his vehicle, going by one of his earlier posts (post no. 20) !

Last edited by mooza : 29th June 2010 at 08:19.
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Old 25th July 2010, 16:10   #39
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Since this thread was about cutting off coils and then reversing the mod by replacing it with stock springs, I thought I will link up this interesting and related thread here, which I missed all these days :

http://www.team-bhp.com/forum/techni...lower-car.html (How to lower a car...?)

Post no. 4 in the above thread looks to be a better option than cutting off coils, since the mod can be reversed easily if required. But I wonder if these spring clamps are available here in India, and whether the clamps will hamper the performance of the springs, in their present design.
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Old 26th July 2010, 21:48   #40
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i will definitely not recommend this clamp on a SUV like scorpio or any daily drive for that matter.
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Old 7th August 2010, 20:37   #41
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It seems a lot of you guys are not liking cut springs on cars!

In the UK it is fairly common practice as a budget modification. As people have said the spring rate increases and if the bump stops are left original you shouldn't bottom the shocks out.

The comments regarding it altering the alignment geometry are correct. You have to consider though that any change to the ride height will effect toe, castor and camber angles. This is true though both for cut springs and lowering kits manufactured specifically for an application. Any change to ride height will require an alignment check and ajustment. Care must also be taken to ensure that they are cut evenly as a pair. The corner weighting will be changed but as long as its changed evenly it is not usually an issue.

Cut springs will pass the yearly MOT test in the UK, as long as they do not dislocate from their perches when the vechile is jacked up. many get around this by drilling holes in the spring mounts and using metal cable ties to secure at the top and bottom.

I've included a couple of pages taken from Herb Adams book, Chassis Engineering that covers the maths involved for cut springs and how to calculate the new spring rate if anyone is interested in reading it.

I have run with cut springs on several cars over the years and while it is in no way as good as a set of dedicated coilovers it is often a big improvement over stock set up and it costs nothing to do.

I rate it as a means to lower ride height, reduce body roll and stiffen springs when you have a tight budget
Attached Thumbnails
I reduced the body roll in my Scorpio!-cut-springs-003.jpg  

I reduced the body roll in my Scorpio!-cut-springs-004.jpg  

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Old 8th August 2010, 14:51   #42
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Thanks a lot, doughnutter, for sharing this information on this thread !

Any quick tips / methods to stiffen the rear leaf springs ? The only way it is done here in most places is to add a leaf to the existing leaves, or re-arch them (I do not know if re-arching increase the stiffness to a great deal, though). Adjustable distance between the shackle / pivots to shorten the effective length of springs, perhaps ?

Cheers, Mooza
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Old 8th August 2010, 15:13   #43
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It is rare for people to increase the stiffness of springs in my experience, not to say it doesn't happen though!

The main times I have encountered leaf springs have been working on historic rally cars such as Mk1 and 2 Escorts (theres a picture of a mk 2 in my introduction thread). We usually lowered the cars by removing a leaf or fitting lowering blocks.

I am however looking to increase the stiffness of the leaf springs in my Transit car transporter and the most logical option appears to be to go for some bigger springs from a tipper truck in the same model range. These are a little larger than the stock ones and also have an extra leaf in them.

I'd say your best bet would be to look for some stronger leafs from a similar car in the range or add another leaf.

I havn't looked into the options of moving pivot points around for my application as it is so much easier to just swap over to the commonly available parts.

Hope this helps
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Old 8th August 2010, 17:27   #44
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Originally Posted by doughnutter View Post
I havn't looked into the options of moving pivot points around for my application as it is so much easier to just swap over to the commonly available parts.
Hope this helps
Thanks doughnutter.

I was actually thinking of the idea of having optional multiple pivot points readily available on leaf spring vehicles, so that the changeover between stiff and soft spring rates could be accomplished easily by just selecting the required pivot positions, thereby making the effective spring lengths easily selectable based on our ride and handling preferences.

For now, as you suggested, I am thinking of adding a leaf to stiffen my sagging leaf springs, which touch the bump stops more frequently than I need, on load
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