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Old 1st April 2011, 19:55   #1
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Default Coil Spring Adjusters : VFM Fix for the Honda Civic's (lousy) soft rear suspension?

The Civic's handling has a dual-personality; drive alone or with one passenger in the front, and the handling is satisfactory. The front end is sharp, and the rear sufficiently planted for a family sedan. The dynamics, brilliant steering, slick gearshift and high-revving engine can be thoroughly entertaining on long drives. BUT load the rear up with 2 or 3 passengers, and the Civic's derrière goes for a toss! With 4 or 5 onboard, the front is still sharp, but the soft rear is bouncing all over the place. And worse still, easily bottoms out in the middle of a corner, leading to completely unpredictable behaviour. You'd think that the front & rear belong to different cars!

As many of you know, I'm going to be getting a performance suspension for sure, within the next 10,000 kms or so. However, not everyone wants to spend 40K on an after-market suspension and I'm hoping this thread helps those of you suffering from ultra-soft rear suspensions (including, but not limited to Civics) with a cheap solution.

The last straw was THIS (taken two weekends back on a highway trip, with full load of people and luggage):
Coil Spring Adjusters : VFM Fix for the Honda Civic's (lousy) soft rear suspension?-19032011637.jpg

I'd heard about coil spring adjusters a short while back, and was willing to try, especially since it's a cheap mod widely used by Forum'ers across the globe. Cost = Rs. 4,000 - 4,500 for a set of 4, and 1/2 of that for only the rear (including installation charges). Thanks to Jaggu & Psycho for sharing their comments & criticisms on the Mod. This part is very popular in the UK, especially amongst station wagons without self-levelling rear suspensions. In fact, the manufacturer of this part (Auto-Runner) accepts that his is a copy of UK products, and doesn't take any credit for innovation. Auto-Runner has apparently been used in the Raid de Himalaya and on the Chennai track.

Most people install coil spring adjusters on all 4 ends. Reason I installed coil spring adjusters only at the rear? I'm extremely happy with the Civic's front!! It's only the rear that I have a complaint with. NOTE : If you have the face-lift Civic with a fresh, stiffer rear, you probably don't need this as much as the older Civics running suspensions with over 20,000 kms on them.

You can install coil-spring adjusters at the top of the spring (working at all times), in the middle (effective under mild to full load) or at the bottom (comes into play only under full load). I chose to install it at the top, as per Psycho's advice.

What you'll like:

• The rear suspension doesn’t make “thud thud” noises when going over large bumps anymore.

• The rear end bounciness is 80 - 90% gone; the back feels a lot more planted. Nearly Octavia-like. The excessive vertical movement from the back (over imperfect patches of tarmac) is nearly eliminated.

• About 12 - 15 mm of clearance gained with 3 people on the backseat. All cars "sit" with 3 on the backseat; my Civic now seems to sit as much as most other sedans. It's not abnormally low anymore (take off position) like other stock Civics.

• I was told that this mod would make the ride stiffer. However, after driving for 40 odd kms, I don't feel any noticeable deterioration in ride quality. This is probably because I've installed the Autorunner only at the back.

• 15 minutes to install. 15 minutes to uninstall. Completely reversible.

• Claimed by manufacturer : Bottoming out reduced. I'll know more after the next weekend trip, when us Mumbai Mods are heading out for a 400 km drive on one of my favourite driving roads.

What you won't like:

• Increase in tyre wear. Manufacturer claims 5% (thus, we can safely presume 10%).

• Those who get it installed at the front, as well as the rear suspension, will surely feel a stiffer ride. For Civics, I only recommend a rear end install.

• Little information on long-term effectiveness & reliability. Guess we'll find out on this forum.

• Stress on the rest of the spring increases. While it's claimed that OEM springs are over-engineered enough to handle the additional stress, we'll only know after logging on the kms.

• One bloke on a UK forum said that the coil spring adjuster may "slip out" of the spring under hard conditions (I presume, when the spring is stretched out). However, I have yet to find a report of the same happening.

• Cannot be used for leaf-spring rear suspensions (Most home-grown UVs and some older cars).

• Wheel alignment required right after installation.

The claimed life of this part is 5 years / 50,000 kms. That's about the time when you would need to overhaul your OEM suspension.

Following pictures taken with a full tank of fuel and about 22 kilos of audio equipment in the trunk. My car is also 4+ years old, hence the original suspension will inevitably develop some sag. While a 1 inch Auto-Runner seems to work perfectly for me, carefully choose the right size for yourself.

0 People Stock:
Coil Spring Adjusters : VFM Fix for the Honda Civic's (lousy) soft rear suspension?-0-people-stock-sam_0002.jpg

0 People with Mod: Feels nice to drive a Civic that isn't droopy anymore. Compare front & rear wheel arches in both pictures. While it's not that evident from the pics, my Civic used to "sit" from the back, even when parked with no one onboard.
Coil Spring Adjusters : VFM Fix for the Honda Civic's (lousy) soft rear suspension?-0-people-mod-sam_0033.jpg

3 people on back seat + Stock setup: Notice how the wheel arch goes over the tyre.
Coil Spring Adjusters : VFM Fix for the Honda Civic's (lousy) soft rear suspension?-3-people-stock-sam_0003.jpg

3 people on back seat + Modification installed. Zoom into the pic and you'll be able to see the tyre's full circle. About half an inch higher (12 - 15 mm increase). That much more ground clearance under load too!
Coil Spring Adjusters : VFM Fix for the Honda Civic's (lousy) soft rear suspension?-3-people-mod-sam_0034.jpg

The main two problems with the Civic are poor low-end torque and the soft-rear. Either solved now. I'm getting her tuned close to just how I want. Link to my other three mods:

1. Performance exhaust (Honda Civic Dyno Run no.2 - With performance exhaust)

2. Typhoon Intake (Honda Civic Dyno Run no.3 - With K&N Typhoon air intake)

3. ICE Install

*Update after 180 kms drive on 8th April, 2011

Quote:
Originally Posted by GTO View Post
Report after 180 kms on the highway with 5 onboard + a trunk full of luggage

- With full occupancy onboard (5 + fully loaded trunk), the Civic did not scrape over speed breakers; this was a revelation. Even the poorly designed toll naka speed-breakers were dismissed off without complaint.

- The car is bottoming out a LOT less. Before, the suspension used to easily bottom out on road dips & ups at any speed over 50 kph. I would say the bottoming out is 60 - 70% less than before. Even the rear end bounciness is far better controlled.

- Unfortunately, it's NOT improved the full-load handling at all. Feels about the same (no advantage), and there is no perceptible difference in grip, nor any perceptible decrease in body roll (still rolls the same as it did before with 5 onboard).
*Update after 180 kms drive on 11th April, 2011

Quote:
Originally Posted by GTO View Post
Update after a 180 kms drive with ONLY driver + 2 passengers:

- Plan for performance suspension back on . This Mod does absolutely nothing to the dynamics or grip levels. Car behaved just as it does on a ghat section that I'm very familiar with. Understeer on the limit included.

- Big area of improvement : No mid-corner bottoming out (severe problem with stock Civics). Because of this improvement alone, I'm sticking with Auto Runner (until I get her a set of Koni FSDs).

- Scraping problem over speed-breakers nearly eliminated, and I'm talking with 5 passengers + fully loaded trunk. The only one breaker where I really hit the bottom is at the end of the trip, where I was distracted & didn't slow down for an XL size bump.

Last edited by GTO : 13th April 2011 at 09:59. Reason: Adding updates from last weekends drive
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Old 1st April 2011, 19:58   #2
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Default Re: VFM Fix for the Honda Civic's (lousy) soft rear suspension?

Installation

The 1 inch tall Auto-Runner used on my Civic. The rubber feels very high in quality. Claimed that it can compress to as little as 5 mm when required (under stressful conditions):
Coil Spring Adjusters : VFM Fix for the Honda Civic's (lousy) soft rear suspension?-00.jpg

Coil Spring Adjusters : VFM Fix for the Honda Civic's (lousy) soft rear suspension?-01.jpg

Stock suspension:
Coil Spring Adjusters : VFM Fix for the Honda Civic's (lousy) soft rear suspension?-03.jpg

Measuring the spring circumference:
Coil Spring Adjusters : VFM Fix for the Honda Civic's (lousy) soft rear suspension?-04.jpg

Matching the same on the coil spring adjuster:
Coil Spring Adjusters : VFM Fix for the Honda Civic's (lousy) soft rear suspension?-05.jpg

And cutting to fit:
Coil Spring Adjusters : VFM Fix for the Honda Civic's (lousy) soft rear suspension?-06.jpg

Spraying regular soap water prior to installation:
Coil Spring Adjusters : VFM Fix for the Honda Civic's (lousy) soft rear suspension?-07.jpg

Insert, and then slide it up:
Coil Spring Adjusters : VFM Fix for the Honda Civic's (lousy) soft rear suspension?-08.jpg

Installed:
Coil Spring Adjusters : VFM Fix for the Honda Civic's (lousy) soft rear suspension?-09.jpg

Last edited by GTO : 2nd April 2011 at 14:23.
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Old 2nd April 2011, 14:35   #3
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Default Re: Coil Spring Adjusters : VFM Fix for the Honda Civic's (lousy) soft rear suspensio

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Old 2nd April 2011, 15:03   #4
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Default Re: Coil Spring Adjusters : VFM Fix for the Honda Civic's (lousy) soft rear suspensio

Rush a really innovative and cost effective way to increase the GC using the coil spring adjuster. What is the guarantee that this wouldn't pop out from the spring ?
I know you already mentioned that in the 1st post, but then on our Indian roads would this thing really stay put ? I guess only time will tell if this would actually prove to be a cost effective mod.

The quality of the product looks great though.
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Old 2nd April 2011, 15:04   #5
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Default Re: Coil Spring Adjusters : VFM Fix for the Honda Civic's (lousy) soft rear suspensio

A mod without (major) modifications ! I wish something like this was availble for the Ikon .. but the Ikon does not have a coil spring. I have this problem in the Ikon when the boot is loaded and there's 2 people in the back. The corner/edge of the rear tyres are got scarred during my last trip.

Last edited by condor : 2nd April 2011 at 15:07.
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Old 2nd April 2011, 15:56   #6
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Default Re: Coil Spring Adjusters : VFM Fix for the Honda Civic's (lousy) soft rear suspensio

While driving around in Pune, have not faced any bottoming out issue on public roads but once in a while at some parking lots.

But on our highway trips we have had some bottoming issues, and it happened twice on our Goa visit 2 days ago.

So this option will definately be looked into.

Thanks for the detailed posts on the product as well as the installation.
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Old 2nd April 2011, 16:23   #7
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Default Re: Coil Spring Adjusters : VFM Fix for the Honda Civic's (lousy) soft rear suspensio

Quote:
Originally Posted by rjstyles69 View Post
What is the guarantee that this wouldn't pop out from the spring ?
Not heard or read a single instance of the same (though many expressed a doubt).

Quote:
The corner/edge of the rear tyres are got scarred during my last trip.
Wider tyres?

Quote:
Originally Posted by mdsaab View Post
But on our highway trips we have had some bottoming issues, and it happened twice on our Goa visit 2 days ago.
Also because, when you are on the highway, there is more load at the rear (seat and boot)?
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Old 2nd April 2011, 16:45   #8
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Default Re: Coil Spring Adjusters : VFM Fix for the Honda Civic's (lousy) soft rear suspensio

Quote:
Originally Posted by GTO View Post
Also because, when you are on the highway, there is more load at the rear (seat and boot)?
Absolutely, but many a times we pack lightly and sometimes we don't pack at all(spontaneous getaways). But Goa as most places around India have these horribly designed speed breakers, somewhere or the other, and recently they have been quite successful at finding us. i just wince before going over them knowing fully i am going to hear a THUD! it takes the HIGH out of highway runs.

Do we order these adjusters online or are they available at stores in Mumbai and Pune? Would like to fit them, to get the HIGH back on our highway drives. Also regarding fitting them, can Honda install them? or do we need a specialist?

Also could you please reccomend how to choose the size we would need? 1 inch did the trick for you.
For your info ~
We travel light most of the times,
My wife at the back - Daughter in the car seat next to her.
Me in the front ~ driving ofcourse.
Rarely do we take a front passenger with us, but if needed for calculations then please include.

Last edited by mdsaab : 2nd April 2011 at 16:52.
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Old 2nd April 2011, 16:55   #9
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Default Re: Coil Spring Adjusters : VFM Fix for the Honda Civic's (lousy) soft rear suspensio

Hi,
Effectively increasing the spring rate by making one coil less operative (as opposed to cutting off a coil and using spacers). But reversible, which is a huge advantage. Should make the handling sportier.

IMHO the floating feeling from the back is better handled by changes in damping than in springing.

If the original spring is not rising rate, should position make a difference?

From my experience of polymer products made here, I would change it every year, at most every two.

Anyway, cheap enough to discard, reversible. What more can one ask for.

Regards
Sutripta
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Old 2nd April 2011, 17:09   #10
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Default Re: Coil Spring Adjusters : VFM Fix for the Honda Civic's (lousy) soft rear suspensio

Thanks for the heads-up, Rush.

A simple yet interesting modification, in effect converting the coil into a dual-rate spring because of the compressibility of the material. A single coil in this case (and if need be, even 2 or 3 coils) is being made stiffer by interposing the rubber material in between. Also acts partly as a bump stop, preventing the spring coils from compressing completely. Totally dependent on the quality of rubber used in the construction of the material. Maybe 50,000 km is too much, but as you mentioned, time will tell - even bump stops wear out on a heavily loaded car in less than 50,000 km.

Different from using a spacer to preload the springs, and would not stiffen up ride quality in unloaded condition (which using a spacer to preload the springs does). Nor would it raise ride height to a large extent in unloaded condition, the trick being to choose the right width of material, corresponding to the space between each coil.

I wonder why tyre wear should be an issue with using this (unless we are talking about extra wear just because of running extra load), and why wheel alignment should be affected (requiring wheel alignment soon after installation). It doesn't alter the camber or thrust angles of the rear wheels/tyres, nor changes any other suspension geometry in unloaded condition. In fact, it would reduce negative camber under full load by preventing full deflection of the rear independent suspension. Maybe, just maybe, turns at racing speed can wear out tyre shoulders a bit more because the treads don't remain as flat with the road when this gizmo is installed.

In case of coil-sprung vehicles with non-independent rear suspensions (live axles), even this won't be a factor (camber angle doesn't change with load).
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Old 2nd April 2011, 17:12   #11
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Default Re: Coil Spring Adjusters : VFM Fix for the Honda Civic's (lousy) soft rear suspensio

Nice so within one week you ordered and fitted it also eh As i said i dont think this mod will be a big issue, as sutripta said its taking one coil off the equation, effectively that much GC will be saved. Let us see how this mod works out in the long run, my only worry is the additional strain on the spring, but shouldn't be a big one.
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Old 2nd April 2011, 17:22   #12
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Default Re: Coil Spring Adjusters : VFM Fix for the Honda Civic's (lousy) soft rear suspensio

Hi SS,
For the 'spacer' not to come out with the spring at full stretch, the free height of the 'spacer' will have to be quite a bit more than the intercoil distance at full stretch. Thus under nominal loaded condition, it will act as a substantial preload. The car will ride slightly higher. Which can/ will change suspension geometry. Also, I think the instruction leaflet doesn't distinguish between front and rear!

@Jaggu: One coil is not taken out of the equation, it is made 'stronger'. Or look at it another way. As if you cut of a coil, and replace it with a 'stronger' coil.

Regards
Sutripta

Last edited by Sutripta : 2nd April 2011 at 17:28.
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Old 2nd April 2011, 17:53   #13
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Default Re: Coil Spring Adjusters : VFM Fix for the Honda Civic's (lousy) soft rear suspensio

Quote:
Originally Posted by Sutripta View Post
For the 'spacer' not to come out with the spring at full stretch, the free height of the 'spacer' will have to be quite a bit more than the intercoil distance at full stretch. Thus under nominal loaded condition, it will act as a substantial preload. The car will ride slightly higher. Which can/ will change suspension geometry.
I presume the install happens without removing the coil assembly from the car, but after jacking up the body only - allowing the spring to be at full stretch without vehicle load on it (but a little pre-compressed as the original fitment would be). In this condition the only parameter that can change is the camber angle. Now, the 'spacer'/device is being inserted by hand, using simple soap to lubricate while it is being inserted - it might compress the rubber to some extent, but how much would it push the coils apart? IMO not much (maybe a couple of mm if at all). Also, preload should involve compressing the coils rather than pulling them apart - correct me on this.

Once the vehicle load comes back on the spring, the camber returns to almost original specifications. With one or two passengers in the rear seat, the original camber angle would have been restored. Another question is, does the Civic rear suspension have a rear camber adjuster, or does it involve using shims to achieve results? And what was the change in suspension geometry noticed, when wheel alignment was checked after installing the device? Rush, could you enlighten us on this please?

Quote:
Originally Posted by Sutripta View Post
@Jaggu: One coil is not taken out of the equation, it is made 'stronger'. Or look at it another way. As if you cut of a coil, and replace it with a 'stronger' coil.
In effect converting it into a dual-rate coil spring (rather than a rising-rate coil), is that right?
Quote:
Originally Posted by Sutripta View Post
If the original spring is not rising rate, should position make a difference?
I agree - it shouldn't make a difference.

OT: I mistook the fellow's shoes for some kind of suspension component at first glance!
http://www.team-bhp.com/forum/attach...pension-06.jpg

Last edited by SS-Traveller : 2nd April 2011 at 17:59.
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Old 2nd April 2011, 18:18   #14
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Default Re: Coil Spring Adjusters : VFM Fix for the Honda Civic's (lousy) soft rear suspensio

One doubt, does it have a stopper or something to keep it in place and prevent slipping down the coil?
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Old 2nd April 2011, 18:21   #15
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Default Re: Coil Spring Adjusters : VFM Fix for the Honda Civic's (lousy) soft rear suspensio

Quote:
Originally Posted by SS-Traveller View Post
I presume the install happens without removing the coil assembly from the car, but after jacking up the body only - allowing the spring to be at full stretch without vehicle load on it (but a little pre-compressed as the original fitment would be). In this condition the only parameter that can change is the camber angle.
Should depend on suspension setup. What about semitrailing arms. But you are right in that the major change is in camber.

Now, the 'spacer'/device is being inserted by hand, using simple soap to lubricate while it is being inserted - it might compress the rubber to some extent, but how much would it push the coils apart? IMO not much (maybe a couple of mm if at all).
I'm sure they'd use some sort of leverage. More than just finger squeezing.

Also, preload should involve compressing the coils rather than pulling them apart - correct me on this.
Preloading the rubber strip.

In effect converting it into a dual-rate coil spring (rather than a rising-rate coil), is that right?
Don't think so.
Maybe the warnings about tyre wear and suspension geometry were put in by the legal department!

Regards
Sutripta
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