Sticky?: Suspension Theory (extended) - Unofficial Honda FIT Forums


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Old 05-06-2008, 02:48 PM
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Sticky?: Suspension Theory (extended)

(Mods: When I edited the original thread, I apparently went oer the 50k word limit by 25k words. This is what I chopped off in order to cut the other thread's size down. if stickied, please delete this stuff in parentheses)

Part 2

SHOCKS, SPRINGS, COILOVERS


Don’t run the OEM dampers with any lowering springs, Progressive rate springs don’t have a definitive spring rate because as their compressed their rate will increase, although they will be more comfortable than a linear rate spring, which rate will always stay constant.

“For Street use, It really makes very little difference what suspension you buy. If you are looking for a soft ride, pick one with a low spring rate. Dampers, do make a difference here. However ride quality is mostly influenced by Mid to high shaft speed valving (mostly bump). And really good single ajustible dampers, ones that allow you to tweak your cars hanlding the best, Should only adjust low speed rebound.

And this is why what damper you choose for street use doesnt really matter... Because most if not all of these "coilover" companys run Single adjustible dampers that adjust both bump and rebound with the same knob, which is silly for any sort of tuning for handling. AND the dampers the do run adjust mostly in the Mid speed valving range, limiting their usefull ness for any thing other then tweaking your ride quality.”

“Sure “pre-built” coilovers are easier. They are very convient, the car handles better than stock but not as well as it could. With a bit of luck someone else has “tuned” the coilover to your car. Will it be tuned specifically for you, no. They are tuned for a wide variety of customers with many different wants out of a suspension kit. Most of which are street drivers.

If you decide to order individual suspension parts then you can choose exactly what you want for your car, the use of the vechile, and your own driving style. Can a “pre-built” coilover compete with a separate spring shock combination, maybe/maybe not.

If you are only driving you car on the street and you will never see the track or any type of competition then a “pre-built” coilover is probably fine for you. If you want the absolute best out of your car and can take the car there then I would say stay away from most of the “pre-built” coilover kits. Either way it won’t matter if this is a street car you will never get the max out of your suspension on the street, and chances are your car isn’t properly prepared anyway, why is this, you don’t know what adds that last 10th of a second unless your timed.”.

Why am I in such dislike of any of the “pre-built coilovers? Dampers and Valving!!!!

“With all of the items that come with your coilovers the damper is the most expensive part that comes with the kit. A lot of companies promote the # of adjustment "clicks" on their dampers as a feature, with out posting a dynograph of the adjustment range of that damper.... well its time to start questioning why. Because "32 way adjustible" really tells me squat about the damper other then it is suposidly adjustible. It doesnt tell me what gets adjusted, it doesnt tell me the range in which those things get adjusted in. in order to lower costs, they end up using dampers of a more primitive design. you'll notice that most if not all use dampers that adjust both their bump valving and rebound valving with one knob. There's a reason for this, as dampers of this sort are easier to design and manufactur (theres only one set of Valve stacks that need to be turned with the adjuster, Vs ones where you only adjust rebound that have two sets of valve stacks, one that gets alterd by the adjustment knob and one that doesnt). Great for the company as they can sell their "coilovers" for less, bad for tuners because you now have an inferior damper. Also valving adjustment range tends to be very limited with the "cheep" coilovers.

In the whole, why would some one want a single adjustible damper to only adjust Rebound rather then Bump and rebound at the same time... well, that deals more with ride quality and how the car reacts to rough surfaces and impacts. See, bump valving has a much bigger influence on how the car reacts to impacts then rebound... It could be said that stiffer bump valving sort of Fakes a higher spring rate. The problem with that is, since they have the side effect of "faking" a stiffer spring, you are also "faking" a higher suspension frequency.... meaning the car will have less traction over bumps and rough surfaces. With a damper that adjusts bump and rebound at the same time, you end up running in to an issue of "I need stiffer valving to get the car to handle and respond the way I want, but I cant run to high of a bump valving with out making the car unstable in turns that arnt perfectly smooth"

"Low speed Valving deals primairly with Handling, as it influences how quickly weight gets transfered around the chassis.
High speed Valving deals primairly with how the shock reacts to impacts, such as bumps and ruts....
Mid speed Valving deals a bit with both.
then you get in to Bump Valvling Vs Rebound Valving.
Bump Primiaily deals with ride quality.
Rebound Primaily deals with handling."

There you have it this is why “pre-built” coilovers are not ideal for competition. For most these are perfectly fine for daily/street driving, but if you even think you will do any competiton then double think your purchase of a “pre-built” coilover.

SPRING RATES, WHEEL RATES, ROLL COUPLE DISTRIBUTION AND SUSPENSION FREQUENCIES

Spring rates are the force it takes to compress the spring. A linear spring has a set rate. A progressive spring doesn't, it will continue to [rise] in rate as it is compressed. Not so good for competition. Spring rates are eh, its the wheel rate that is the important information to know. The wheel rate will always be less than the spring rate, that is the motion ratio of the suspension, picture it as a lever. The wheel rate is the spring rate at the tires contact patch. Who cares what your wheel rate is, well that is the best way to figure out your roll couple distribution. Roll Couple is the balance of Roll resistance at the front of the car Vs the rear of the car and directly influences the oversteer/understeer balance of the cars Roll couple. Roll couple is adjusted with spring and anti-roll bar rates. All that really is is the difference in stiffness (roll resistacne) front to back. The stiffer end of a vehicle will lose traction first. So if a car’s front suspension is stiffer that the rear, the roll couple distribution will produce understeer because the front end is handling more weight transfer. Chances are your car is heavily biased to the front. This is why the car understeers in most situations.

Let me start with the higher the suspension frequency grip decreases. SO WHAT? Well this frequency is a measure of how many cycles per minute or in a second, the car would go through and bounce up and down on springs alone. This matters greatly to you because the stiffer the suspension is the less contact patch will be touching the ground over rough surfaces, and if the tires in the air your not gaining traction or grip. The more grip your tires can make, the more force your putting into the car so you will need to up the resistance to body roll to keep it at an acceptable level. Race tires need a much stiffer suspension than a street tire. Cause their grip is that much higher and will cause the body to roll, losing camber and reducing grip.
In simpler terms...you want to run the softest springs you can get away with that reduces body roll to an Livable level, and has an appropriate roll couple balance to give you the oversteer/understeer charateristics you want with the most grip your car can achieve.

Tuning a car to be neutral in almost all turns is an impossibility. Also neutral would not be the "fast" way around alot of turns. And you will only find out an ideal setup against the clock not on the street."

SPRINGS
(from turnfast.com)

Springs are primarily responsible for keeping the tire in contact with the road surface over bumps and dips.
In the realm of physics, springs are noted as being efficient machines for storing mechanical energy. When a spring is compressed, the energy required to perform the compression is stored. When the compression force is removed, the spring returns to its original shape. No additional energy input is required. A spring can also be stretched (to a point), and it will return to its original shape. All this depends on the use of effective materials of course.

What does a spring do?
In a car, compression of the suspension spring is caused when the wheel travels across the front side of a raised bump. A portion of the energy used to cause forward motion of the vehicle is redirected causing the wheel to travel up, which compresses the spring. The spring stores the vertical energy, and as the wheel travels down the backside of the bump, the energy stored in the spring pushes the wheel back down. For safety and handling, this has the significant benefit of keeping the tire in contact with the road surface as the tire travels over a bump. A similar process occurs for dips, except that the spring elongates rather than compresses to start with.
Without springs, the wheels would transfer the redirection of the vertical energy into the vehicle chassis and cause the vehicle to bounce off the bumps. This would both be annoyingly uncomfortable to the passengers (a concern to street car manufacturers), and the driver would momentarily lose some or all of the ability to steer, accelerate or brake as traction from the tires would be lost (a safety concern for all, and a maximum performance concern for racing).
With springs, the vehicle body can maintain a relatively linear path (providing comfort for the passengers), while the wheel travels up and down over the bumps (allowing for continuous safe vehicle control, and continued traction for maximum racing performance).
Therefore, the purpose of the spring in an automobile is to isolate the wheel assembly from the body, and allow the tire to maintain contact with the road over surface imperfections.

Spring Stiffness
Relative to its shock absorbing function, the spring must be stiff enough to prevent full compression or elongation in large bumps and potholes. However, it must also be soft enough maintain good contact with the road. The softer the spring the better the road contact over bumpy surfaces. However, the stiffer the spring, the better the resistance to bottoming out on large bumps. Somewhere between these extremes is a range of good spring rates (stiffness) to work for the expected environment.

Wheel Travel & Body Roll
In order to handle bumps and dips, the entire wheel assembly is designed to have a certain amount of vertical travel length from full extension to compression. The rougher the road, the more wheel travel is needed, and the longer the overall spring length needs to be. Factory passenger cars are designed to function well over a broad range of conditions, and the suspension system in particular must be prepared to compensate for potholes, freeway expansion joints, rutted gravel roads, and other less than ideal road surfaces. Therefore, a street car is designed with quite a bit of suspension travel length (think of how far you have to jack up a car's body to get the wheel off the ground--that's about half the wheel travel)). In a high performance sports car (i.e. of the Porsche, Ferrari, Viper, and NSX type), manufacturers assume a more limited range of road surfaces, and design in less wheel travel by a of couple inches. In the typical sports car or sports sedan of the Mustang, Camaro, Eclipse, Integra, and BMW 3 types, the suspension is a little better than the general sedan, but it's really not a great deal different.
In racing, we can assume a certain degree of ideal conditions, or at least more ideal than public roads. In a stock street car, even notoriously "bumpy" race courses feel glass smooth compared to most public roads. In these conditions, the purpose of the spring can be focused to maintain maximum and consistent contact of the tire with the relatively much smoother road surface. Under these conditions, very little wheel assembly travel is required. The spring can be optimized for smaller wheel travel conditions. For example, a CART or Formula 1 race car driven on smooth courses may only have 1/4 to 1/2" of total suspension travel!
How does wheel travel impact handling? Well, just from the CART example given above, we might assume that shorter wheel travel is better. And, of course, it is. Though the wheel assembly travels up and down, it does not do so on a linear path. The wheel assembly is at some point fixed, and the wheel assembly actually travels in an arc. Whether the body stays put, and the wheel travels (through bumps), or the wheel stays put and the body travels (body roll), this has impact on the camber angle of the wheel which changes the tire contact patch shape.
Therefore, for racing conditions, limiting the wheel travel distance is a desirable thing. For street cars, the use of lowering springs (shorter and stiffer) is one method to reduce wheel travel. In extreme cases, it will also be necessary to use shorter shocks.

Roll Stiffness
So far we have used bumps in the road to illustrate how springs behave. Springs are also acted upon by the forces of acceleration, braking, and cornering. The momentum of the vehicle body in cornering, braking, and acceleration transfers into the springs causing compression and elongation. This is an easy to see effect of weight transfer as it results in visible body roll -- both the side-to-side roll we're mostly familiar with during cornering, but also front-to-back roll -- particularly the "nose dive" under hard braking.
Body roll by itself is not necessarily bad. If the four tires remain flat on the road surface with balanced downforce, who cares whether the car body is parallel to the road or not (aerodynamics aside). What body roll does though is change the angles of the suspension components to the wheel assembly (which we call suspension geometry).
This is pretty much the same thing as we discussed above with wheel travel, except this is from the opposite perspective. With the wheel on the fixed plane of a smooth road, the body now travels, and causes the wheel assembly to travel in the arc we described. This changes the camber and tire contact patch particularly of those tires which are unloaded and the suspension elongates.
Aside from bump absorption, the spring also contributes to the roll stiffness of the car--the ability to resist dive under braking, squat during acceleration, and body roll during corning. The anti-roll bars also play a roll in this, and the two combined create the total roll stiffness of the car. Stiffer springs will resist body roll more, reduce change in the suspension geometry, and maintain a more consistent tire patch size.
Note: many people are under the misconception that body roll causes weight transfer. This is not true. See the weight transfer article for details about this.

Spring Stiffness for Racing and Street Use
The spring's roll resistance characteristics helps to resist the forces during dynamic changes, and make the car more stable during the transition. This implies a stiffer spring is needed to minimize the compression and elongation, and therefore minimize the change to the suspension geometry.
However, even purpose-built race cars cannot simply use the stiffest spring available. If we return to the case of having no springs at all (the ultimate in stiffness), even a "smooth" race track would be violently bumpy without some suspension dampening. At some point the spring becomes too stiff for the road surface, and the vehicle will lose traction as it bounces over surface imperfections. The race technician and driver have to find the most effective balance between being soft enough to allow the tire to stay in contact with the road surface over bumps, and being firm enough to control suspension geometry and keep the tire as flat as possible on the road surface.
A driving enthusiast's car which does double duty on the street and the track has a larger window to find compromise in than does a race car. Putting full race springs on your street car may seem the macho thing to do, and though your car should be faster on the track, it will make your life miserable on the street. In fact, it is quite likely to cause damage to other suspension components when you come across that surprise pothole.
Today, after-market springs offer features that not too long ago would have been found only on race cars. The research done in sports car class racing has resulted in several manufacturers producing high performance progressive rate springs for virtually all sport enthusiast cars that allow an acceptable comfort level on the street yet significantly increase handling performance over the stock springs.
Most factory stock springs have a constant or nearly constant factor of stiffness called the spring rate. As the spring is compressed or elongated, the force required to change the spring's length stays the same. The spring rate is linear as the spring goes from full elongation to full compression. This provides greater comfort across minor and major bumps, but does little to minimize body roll under hard cornering.
Progressive rate springs have a softer spring rate during some initial portion of compression or elongation, but then get progressively stiffer as continued force is applied. This is typically accomplished by changing the shape of the spring. This ability to start soft and get firmer with higher compression allows the spring to accommodate typical street bumps with satisfactory comfort. On the track under high braking or cornering forces, the spring's stiffer region comes into effect to reduce the body roll compared to the stock spring. Compared to a full race spring, there is a little more body roll before the spring takes a firm set, but that's the compromise of a dual purpose car.
Most after-market progressive-rate springs start out about 15% firmer than the stock part, and get stiffer from there. Though they offer acceptable bump absorption, they do give the vehicle a noticeably rougher ride, especially with larger bumps where the spring becomes stiffer. However, given the success of these springs, the comfort for performance trade off is considered well worth it by sports car enthusiasts.
In selecting an after-market spring set, you should know how much stiffer than stock it is, whether it is progressive or linear, and how much it will change the car's ride height. If you're concerned about losing too much ride comfort, you should ride in another car as closely prepared to yours as possible. Some people stiffen their suspensions for periodic racing only to discover they really don't care for it the remaining 97% of their driving time.
You should also know what other suspension changes you're going to make to the car including wheel and tire sizes, and talk with a technician experienced with your car type. Certain combinations of springs, shocks and tire sidewall sizes will function better than others. A mechanic from a specialist shop or race team may offer some advice learned from experimentation and testing.

Using Springs to Lower the Car
One other thing related to spring selection is that of vehicle ride height. On the street, the variety of road surfaces, speed bumps, drainage channels, and steep driveways requires the car's lowest point have a certain practical height above the road to avoid damaging the car.
In racing, ride height has significant impact on the vehicle's center of gravity ("CG") which is one of the major influences in a car's weight transfer characteristics. Ideally, the CG should be as close to the ground as possible, and race cars will be lowered as much as allowed by the rules. Open-wheel formula cars are lowered as much as possible without bottoming out while racing which often ends up being 1/2" or less on very smooth tracks.
The most straightforward way to lower the CG is to lower the car, and the most direct way to do that in a street car is with shorter springs. Most street cars can be lowered somewhat from their factory setting, but there are several practical limitations in the design of the suspension system. A realistic compromise needs to be made that considers the clearance needs for the street, and the suspension system of the car.
Extremely low cars ("slammed" in today's vernacular) may look good (or at least look like the racing sedans they seek to imitate), and if done right will handle better on the track, but there are some limitations on the street. Springs which are too short may cause interference problems with other suspension components such as the shocks. Additionally, the suspension geometry (the connection points, and lengths of it parts) are designed with a certain spring length in mind to keep the wheels in proper alignment. A severely lowered car that does not also alter the suspension will cause the wheels to have excessive camber for sure, and will likely also adversely affect the caster and toe. You might think it looks great, but this will severely reduce the handling performance of the car.
You should consult someone experienced with your car type before just buying the spring which seems to lower your car the most. Such a spring may also require a specific matching shock or other suspension changes to actually improve the handling performance.
Speaking of shocks, it is generally necessary to buy stiffer shocks at the same time you change the springs. Springs alone will lower the CG, and will reduce body roll, but neither is the primary function of the spring. For road imperfections, shocks work in conjunction with the spring, and are designed with each other's ratings in mind. Going over bumps, a stiff spring may resist the first compression well, but without sufficient shock capacity, the car will bounce more than it should afterwards which ultimately reduces the car's handling performance. Also, stiffer springs will prematurely fatigue stock shocks. They'll last a while, but will eventually get weaker and decrease the handling performance.
If you can only afford shocks or springs, either keep saving to get both, or start with the shocks. Performance shocks alone which provide firmer bump and rebound control, and greater control over weight transfer rate, will improve handing performance more than stiffer springs alone will.

Another Option: Coil-Over Springs
There is increasing availability of coil-over suspension setups for street cars. The coil-over is a combined assembly of the shock and spring where the spring rests in a height-adjustable base.
Coil-over setups were designed to optimize racing performance, and so several characteristics of coil-overs seem to make them the ultimate choice in suspension modifications.
First, coil-overs allow the car to be lowered more than conventional shock and progressive rate spring upgrades. This of course is a good thing for weight transfer control, but as we mentioned earlier, can cause real comfort and damage-potential problems for a street car.
Secondly, the spring rates are usually much stiffer than even progressive rate springs, and they're usually linear. On the race track, there's no need for a progressive spring rate, and coil-overs with their racing purpose, aren't intended to use them. This also allows the spring to be shorter which is where the greater lowering potential come from.
The main purpose and advantage of the coil-over design is to allow independent ride height adjustability of each corner of the car. This ride height adjustability allows manipulation of the center of gravity of the car. In particular, by manipulating the front to back or side side to side location of the center of gravity, weight transfer can be controlled to influence specific tires on the car. If you can pre-dispose the car to distribute weight transfer a certain way, you can optimize the grip of certain tires and improve the overall speed of the car through corners.
Raising the back of the car puts the CG more forward. Raising the front of the car pushes the CG more rearward. The left or right side could also be independently raised or lowered. With these adjustments, you can reduce the amount of grip lost to specific tires during weight transfer.
For example on a race track with a high percentage of high-speed right turns, you could set the car up to reduce the weight transfer to outside left tire, and increase the weight that remains on the right rear. Compared to the same car with fixed ride heights, the one with the adjustable coil-overs will be able to increase the overall grip through more even wieght distribution during the dynamic load of the right turns.
So, this sounds like an awesome modification to run out and get, right? Well, yes it is -- for racing. Like we say, for the street this is an extreme modification. You may be die hard, and live with the harshness of the ride, but you'll likely have very grumpy passengers.
It is possible to minimize the harshness by using softer springs, or even progressive rate springs for that matter. However, those springs will tend to be longer, will not allow the car to be lowered as much negating some of the advantage. Some people will use stiff springs for the track, then swap to softer springs on the street between events.

Summary
Springs allow the wheel to remain in contact with the road surface over bumps. The bumpier the road surface, the softer the spring needs to be. In a street car, it's not likely you'll be set up to change springs easily, but in selecting an after market spring, you should understand the balance of ride comfort and track performance you want, and identify the spring best suited to that compromise.
Lowering the car with shorter springs will also reduce weight transfer, but excessive lowering (beyond the design range of the other suspension components) will cause other problems that will diminish handling performance, and potential create very unsafe conditions if the suspension bottoms out easily.
Progressive-rate after-market springs are designed to reduce body roll to maintain better tire contact patch during cornering, and reduce weight transfer while sacrificing only a little ride comfort.
A coil-over spring and shock assembly is generally the ultimate set up for racing. The car is lowered significantly, the springs are usually much stiffer for body roll control, and the ride height of each corner of the car is adjustable allowing tuning control over the center of gravity and weight transfer. Coil-overs are an extreme modification for street use, and renders the ride comfort intolerable on the street for most people.
For all changes to the spring stiffness, especially coil-overs, be sure to test drive a car that has a setup similar to what you're looking at. Ride stiffness is a definate try before you buy situation to make sure you can live with it the 97% of the time you're not racing.

SHOCK ABSORBERS / DAMPERS / SHOCKS
(from turnfast.com)

The primary function of a shock absorber is to dampen the oscillation of the spring after the wheel travels over bumps and dips.
If you've read the springs article, you know that the spring's job is to allow the tire to maintain constant contact with the road surface. It is the spring that actually absorbs the shocks of surface roughness.
So, contrary to their popular name in the U.S., the purpose of the "shock absorber" is not to absorb the shock of bumps on the road. That is the job of the springs. The purpose of the shock is actually to dampen the oscillation of the springs. Reflecting this function, those outside the U.S. refer to shocks as dampeners.
We mentioned that a spring retains energy to allow it to return to its original shape after being compressed or stretched. Unfortunately, a spring will not just return to its original shape and stay there. You've probably witnessed yourself that if you compress or bend a spring it will oscillate back and forth in smaller and smaller increments until finally coming to rest. If you have ever seen an old car bounce endlessly after going over a bump, you have seen what springs will do in a car with ineffective shocks. This is not good for safe control of the vehicle, and it's certainly not any good for effective handling while racing.

Oscillation Control
The shock's primary purpose is to control this oscillation. In a passenger car, the designer has the choice of just how fast the shock dampens the spring. If the dampening is immediate, the car will have better weight transfer rate control, but a harsher ride. If the dampening is a little slower allowing perhaps 2 to 3 oscillations, the ride will feel much smoother.
In racing, we want the dampening to be almost immediate. A vehicle's bouncing on the springs creates erratic shifts in the tire contact patches and mechanical downforce on the tires. Both of these conditions reduce the effective grip the tires have. Any bounce in the body of the vehicle must be eliminated quickly to allow full grip to return as fast as possible to the tires.

Shock Stiffness
However, like springs, it is possible to have too stiff a shock. First, if the shocks are stiffer than the springs, the springs will be overpowered, and will not actually fulfill their bump absorbing function.
Secondly, a shock has a major affect on how quickly weight transfer occurs in the dynamic changes of accelerating, braking, and cornering. The stiffer the shock, the faster the weight transfer occurs. This will help the vehicle have very responsive steering, but the transfer can be too fast for the driver.
During cornering in particular, the driver must be able to induce smooth weight transfer and feel the tires reach their maximum grip. If the weight transfer occurs too fast, the driver will not feel the tires approach that peak grip, and will likely overshoot the traction capacity of the tires causing excessive sliding or spins.

Shock Upgrades
When modifying your car, starting with the most awesome race hardware you can buy is not likely the appropriate starting point. Full-race shocks are going to be too stiff for the street, and will likely cause the car to bounce off of bumps. Additionally, you'll probably not have the sensitivity to feel the grip level of the tires when cornering at maximum speed.
To help with the dual purpose street/track car, and to provide some adjustability for tuning handling performance, there are several after-market shocks that are adjustable. A manual (or even electronic) dial allows selection of several settings which are progressively stiffer. These shocks can be turned to their softest setting (they're still going to be stiffer than stock) for a smooth ride on the street, and their firmest for the track to minimize body roll and increase the steering responsiveness. The adjustability also allows finer tuning of handling performance for a given track. As discussed in the weight transfer and the handling tuning sections, adjustable shocks can be used to help adjust out small amounts of oversteer and understeer.
If you can't afford adjustable shocks, don't assume that stiffer is better in a fixed rate shock. Shocks should be selected knowing the springs they will be used with. Too stiff a shock will overpower the spring reducing its effectiveness. If the shock is not adjustable, then matching the shock to the rating of the springs is even more critical. You sould consult a shop experienced in this matching.
Talk with a technician familiar with your car, and find out what shocks offer the best performance for you car's degree of modification. The "killer" shock for someone else's car may not be the best one for yours.

Summary
The shock's purpose is to control the oscillation of the spring's response to bumps and dips. The stiffer the shock, the faster the dampening. The shock also controls the rate of weight transfer. The stiffer the shock is for compression (or "bump" as it is often called), the faster weight transfer occurs which determines how fast the tires will take their "set" in a corner, and the resulting steering responsiveness of the car.
It is possible to have too stiff a shock which will overpower the springs, and results in weight transfer being too fast for the driver's experience and sensitivity to feel when maximum tire grip is achieved in a corner (generally resulting in a lot of spins).
Shocks need to be selected knowing the ratings of the springs.

Good reads:
http://www.carbibles.com/
http://www.aa1car.com/
http://www.autozine.org/technical_sc...ech_index.html

Last edited by cojaro; 10-04-2008 at 02:26 PM.
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Old 05-06-2008, 02:51 PM
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Dear lord thats long. Nice read.
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Old 05-06-2008, 02:54 PM
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Dear lord thats long. Nice read.
Long but worthwhile in the end.
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Old 05-06-2008, 03:06 PM
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goddamn it i cant rep you...rain check!
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Old 05-06-2008, 03:31 PM
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great write up and great read...now i will have to take even more time in getting springs/shocks/coilovers for my car now that i was dropped with this info. for me to think about.
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Old 05-15-2008, 01:11 PM
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bumpity bump bump
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Old 08-15-2008, 09:10 PM
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Nice article. What would you consider to be the most drop with a set of springs; front / rear for a daily driver w/once a month to spare for serious play? How much drop would you consider it would be necessary to reduce the height of bump stops. ~~ Thanks, in advance.
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Old 08-15-2008, 11:32 PM
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Nice article. What would you consider to be the most drop with a set of springs; front / rear for a daily driver w/once a month to spare for serious play? How much drop would you consider it would be necessary to reduce the height of bump stops. ~~ Thanks, in advance.
Keeping in mind we have Fits, the drop from the springs is subjective. What matters most is the F/R spring rate. You don't want the springs to be so stiff that you can't enjoy it as a DD, but you want to have some sort of performance upgrade for the track.

I can't remember which springs have the softest [relatively] spring rate of the top of my head, but you should shop around and read any reviews for all available springs. I think there are at least 7 different lowering/spring kits for the Fit. Stiffer isn't necessarily better, especially if the car's daily driven.
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Old 10-17-2008, 07:07 PM
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definitely a good read.
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Old 10-17-2008, 07:08 PM
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Good shit.
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Old 10-18-2008, 01:38 AM
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Location: Memphis, TN
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Glad you think so ^_^
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Old 02-14-2010, 01:31 PM
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Join Date: Feb 2010
Location: london
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May I suggest the site: SuspensionCalculator to perform all suspension related calculations
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2007, absorber, bumpy, eclipse, fit, honda, racing, raised, reduce, ride, shock, soft, sticky, stiff, suspension, theory

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