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Old 27th May 2009, 20:17   #31
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Originally Posted by doomsday View Post
Isn't 50% stiffer a lot, for road use? As you said, given the undulations even our best roads have, I've had some hairy experiences with stiffer springs where the car tends to take off at triple digit speeds. I don't know what kind of spring rates those lowering Eibachs come with, but I would rather stay away from all that and work with stock springs.
Well, 50% stiffer on spring rate is not a huge change considering the fact that most aftermarket coilovers are between 400% and 700% stiffer. It is almost a necessity if the owner wants the ride height to be lower by more than an inch or so from OEM.


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I guess it's time to get stiffened shocks then. Should I work with my current worn out shocks or buy new ones and stiffen them?
Buy good aftermarket shocks like Koni or Bilstein. There is a lot more to dampers than just stiffening, and I would trust only the big names to do it right and not cut corners on materials and tuning.


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Strut brace at the front, as recommended by most of you.
If it helps to be a little more clear: STRUT BRACE IS USELESS, unless it is necessitated by higher spring rates.

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Originally Posted by pranavt View Post
Tyres will come a little later I guess, as long as it's the final step in this whole game.
You didn't really read my post, did you? Tires are the first thing you need.
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Old 27th May 2009, 20:28   #32
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Tires will max out sooner? Can you elaborate why with a technical explanation?
Actually its the completely opposite.
Definitely. I'll give an example I have observed and experienced myself, dunno if its tech enough. There was this stock sprung OHC, shod with some 195 Potenzas- not great tires by any means but decent for a stock car, used for some 7-8k odd kilometers. With the stock suspension, at speeds above 150+, the car used to feel like a boat, nose diving sharply under braking and with the car dancing across the tarmac, bobbing up and down when encountered with a mid-corner undulation in a mid-speed corner with killer understeer to boot.

Now this guy went out and got some suspension work done by a rally guy, the setup was excellent, even if a little stiff for daily duties. So again, back on the same roads with the upgraded suspension, but the same rubber- done some 1500 odd km more, still in decent shape. The car felt much more stable and inspired a whole lot more confidence. But a new problem surfaced, the tyres used to give way very quickly. At around the same speeds a gentle squeeze of the brake pedal used to lock 'em, albiet with none of the drama associated with the earlier stock setup. They just locked, with the car going dead straight- since the setup was stiff overall, there was comparatively lower nose-dive and roll in corner. The thing used to slide instead, often ending up in a four-wheel slide which had to be corrected before it got out of hand.

In short, the stiffened setup cut out the drama- but whenever it ensued, it was with little or no warning. So we got him some AD-07s and he is happy ever after. The braking has improved phenomenally, it really feels like the car has undergone a brake upgrade. It hasn't- it is just using the stock setup to its optimal limits- limits that were not explored because of the rubber giving way before the brakes did and the suspension that ran out way before the tyres or brakes did. Now one needs to see the way the speedo needle retards when the brakes are squeezed. This guy went on to say that he would never buy any other rubber.

Hope that suffices. I don't have any data to back all this up its just experience- even though I believe in data more than gut feel.
Next time though, if someone I know is going through these mods from square one, I'll remind myself to log the progress after each stage.

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My comment on Konis was in general. D2 and Hotbits are nowhere in the same league as Koni, Bilsetein, Sachs and Tokico.
Definitely. Not by a long shot...

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Originally Posted by ananthkamath View Post
Well, 50% stiffer on spring rate is not a huge change considering the fact that most aftermarket coilovers are between 400% and 700% stiffer. It is almost a necessity if the owner wants the ride height to be lower by more than an inch or so from OEM.
Yeah those 32-way adjustable stuff is crazy, I haven't checked the specs really but I guess what you said could be in the correct ball park. This example I drove was with lowering springs and STOCK shocks which means stock damping for a higher-rated spring (I assume). It didn't quite feel right. Suppose I want to go stiffer in lower increments- like you said 50%. How do I go about it? Work with the OEM spring (you know where we are going) or is there anything else we can do?

Last edited by doomsday : 27th May 2009 at 20:46.
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Old 27th May 2009, 20:51   #33
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Sorry mods, ran out of the time limit so please merge this post.

@ananth- In addition to above, will a 50% stiffer spring rate call for a damping adjustment? Or does a healthy stock shock has the leeway of working with this increase in the spring rate? Are there any other variables? And obviously this is for the street, with varied road surfaces, bumps and cambers if not worse- common characterstics of Indian tarmac.

Last edited by doomsday : 27th May 2009 at 20:54.
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Old 28th May 2009, 01:16   #34
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Originally Posted by doomsday View Post
It hasn't- it is just using the stock setup to its optimal limits- limits that were not explored because of the rubber giving way before the brakes did and the suspension that ran out way before the tyres or brakes did. Now one needs to see the way the speedo needle retards when the brakes are squeezed. This guy went on to say that he would never buy any other rubber.

Hope that suffices. I don't have any data to back all this up its just experience- even though I believe in data more than gut feel.
Next time though, if someone I know is going through these mods from square one, I'll remind myself to log the progress after each stage.?
If you are saying that putting stiffer shocks will make the brakes lock up sooner, then technically it doesnt add up. Stiffer shocks will reduce brake dive which means the rears are not unloaded like before (and fronts are not overloaded) which means the front should bite harder.
I think what is happening is that the stiffer shocks is making him drive a lot more aggresively and you are carrying a lot more speeds and explioting the limits with more confidence causing all the drama with the tires.
Bottomline is that once you fix the weakest link it will expose the next weakest link.

No doubt the AD-07 is a hi-performance tire and you are going to pick up a ton of grip with it. But for Pranav's purpose and budget which is hi speed touring the GSD should suffice.
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Old 28th May 2009, 02:58   #35
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Originally Posted by doomsday View Post
This example I drove was with lowering springs and STOCK shocks which means stock damping for a higher-rated spring (I assume). It didn't quite feel right.
OEM shocks are compromised for a better ride. Very little, if any, attention is paid to the operating range which matters the most for handling. In addition, the construction of OEM shocks are such that it cannot really handle low speed road inputs (not talking about vehicle speed here) with any kind of finesse. The damping forces generated are just not enough to optimize handling while still maintaining a decent ride.

This results in a shock which is quite a bit underdamped for even the stock springs. So using anything stiffer is out of the question.

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Originally Posted by doomsday View Post
Suppose I want to go stiffer in lower increments- like you said 50%. How do I go about it? Work with the OEM spring (you know where we are going) or is there anything else we can do?
For less than 50% rate increase, cutting the OEM springs is an option but its hard to achieve the rate you want combined with the correct spring preload. Hard to say without looking at the actual numbers.
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Old 28th May 2009, 13:18   #36
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Originally Posted by Mpower View Post
Bottomline is that once you fix the weakest link it will expose the next weakest link.
Very true. Well said. That is the reason the entire setup should be looked at as a whole- not bits of it.

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Originally Posted by ananthkamath View Post

This results in a shock which is quite a bit underdamped for even the stock springs. So using anything stiffer is out of the question.

For less than 50% rate increase, cutting the OEM springs is an option but its hard to achieve the rate you want combined with the correct spring preload. Hard to say without looking at the actual numbers.
Hmm. I thought that resorting to the ghetto option of cut springs wasn't a good idea- as one usually never knows where it'll end up. If executed by someone who knows what he is doing, maybe yes.
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Old 28th May 2009, 17:15   #37
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So I emailed N1 performance in Mumbai. They only have Pedders heavy duty performance coil springs (30% stiffening of suspension) for the OHC. Contacted Methods who didn't reply back. Same with KS Motorsport. Any recommendations on people who'd actually like to do business through email?
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Old 28th May 2009, 17:23   #38
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Originally Posted by doomsday View Post
Now this guy went out and got some suspension work done by a rally guy, the setup was excellent, even if a little stiff for daily duties. So again, back on the same roads with the upgraded suspension, but the same rubber- done some 1500 odd km more, still in decent shape. The car felt much more stable and inspired a whole lot more confidence.
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Originally Posted by pranavt View Post
So I emailed N1 performance in Mumbai. They only have Pedders heavy duty performance coil springs (30% stiffening of suspension) for the OHC. Contacted Methods who didn't reply back. Same with KS Motorsport. Any recommendations on people who'd actually like to do business through email?
I remember Tejas brought this up once before. Check with him and FordRocam. Else check out the rally guy that doomsday talks about. Else D2, Hotbits etc although I haven't seen any reviews yet.
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Old 28th May 2009, 18:01   #39
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Emailed Fahad Kutty, let's see what he replies back with.
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Old 31st May 2009, 23:06   #40
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Nice thread. I have done a lot of research on this. Very busy now and leaving town for a week then. Will post details when i get back.

Go with what doomsday and ananth are saying though. Right on the money.
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Old 1st June 2009, 13:18   #41
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Originally Posted by ankitahuja View Post
I am enjoying every bit of conversation on this thread.

What do you guys feel about a 1998 Type 1 OHC with 195/50/R15 tyres. Running stiffened shocks and stock springs with a strut brace up front.

Are there any specific ways to get your balancing and alignment done in order to enhance the handling in any way?
Thats the same set-up i am running on my OHC(you would know obviously!!!) minus the strut brace and a 55profile tyre. With this set-up low-speeds below 100kmph handling has improved quite a bit but as you reach 130-140kmph on the high-way that floaty feels creeps back in. That planted feel is just not there.....SIGH!!! How i miss my Ikon when it comes to handling and low-end grunt!!

IMHO the OHC's springs are too soft and with the stiffened dampers springs need to be stiffened too. Autopsyche suggested Eibach springs and i think they should complement the stiffened dampers.
Chassis flex also needs to be controlled by strut braces.

Unless you have alloys/wheels with offset way different than the stock set-up allignment does not need extra attention than regular.

@ TO ALL
With lowering springs, with a drop in height of about 1 to 1.5 inches, dont we need to adjust the camber? Till what extent of lowering the height can the stock camber be adjusted?
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Old 1st June 2009, 13:21   #42
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Originally Posted by pranavt View Post
So I emailed N1 performance in Mumbai. They only have Pedders heavy duty performance coil springs (30% stiffening of suspension) for the OHC. Contacted Methods who didn't reply back. Same with KS Motorsport. Any recommendations on people who'd actually like to do business through email?
Hey Pranav,
Did N1 respond by email? cause I had mailed them asking for the suspensions quote but No reply!!
How much did they quote for the Pedders springs? And did they quote for the struts also?

Was looking out for performance ones with a reasonable budget.

Thanks
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Old 1st June 2009, 19:21   #43
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Originally Posted by abhik View Post
@ TO ALL
With lowering springs, with a drop in height of about 1 to 1.5 inches, dont we need to adjust the camber? Till what extent of lowering the height can the stock camber be adjusted?
There is no Camber adjustment on an OHC.
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Old 2nd June 2009, 00:16   #44
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Originally Posted by abhik View Post
IMHO the OHC's springs are too soft and with the stiffened dampers springs need to be stiffened too. Autopsyche suggested Eibach springs and i think they should complement the stiffened dampers.

This is all conjecture. opinion means zero until someone goes and measures the spring rates (not that hard to do) of the stock springs.

Then, someone like me or Mpower who does vehicle dynamics everyday for a living, can do some simple calcs and tell everyone whether they are stiff enough or not.

Who here is willing to do this instead of blindly paying money to someone? I'm sure either MPower or myself will be glad to give some direction to anyone who's willing to do some ground work by themselves before blindly buying parts that may or may not work.


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Originally Posted by abhik View Post
Chassis flex also needs to be controlled by strut braces.
Let me reiterate again, strut brace is BS that has been fed to people by magazines and other vested interests for years and years. The reason is that most strut braces do not feed loads into a stiffer part of the body. They just move the compliance from one part of the body to another.


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Unless you have alloys/wheels with offset way different than the stock set-up allignment does not need extra attention than regular.
Can you explain how wheel offset influences alignment?

Last edited by Mpower : 2nd June 2009 at 06:05.
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Old 2nd June 2009, 01:23   #45
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Originally Posted by Sunilb View Post
Hey Pranav,
Did N1 respond by email? cause I had mailed them asking for the suspensions quote but No reply!!
How much did they quote for the Pedders springs? And did they quote for the struts also?

Was looking out for performance ones with a reasonable budget.

Thanks
16740 + Installation charges for the Pedders "heavy duty performance" coil springs.

Emailed Methods again who replied back with Four Seasons' (Mumbai) number for Eibach lowering springs. I'll be calling up tomorrow. Will post prices of the same.
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