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After months of road testing in various road conditions, different temperature and environments, Roadtamer successfully completed the development of mono-tube shock absorber with canister series for TANK300 (Great Wall brand) at the end of 2021. Main features: 1.8-speed compression rebound adjustable; 2.2-inch rise; 3.60mm body and 22mm piston rod; 4.Upgraded Aluminum canister with heat radiation structure; 5.Anodized, CNC machined 6061-T6 billet aluminum; 6.Adopting domestic top-class cold coiled springs, providing more resilience with much longer life. In 2022, Roadtamer will continue to launch this series for more models. Please stay tuned.

By the end of 2021, CFMOTO Z10 project was started mass production. CFMOTO (ZHEJIANG CFMOTO POWER CO,LTD) is the most famous motorcycle and ATV manufacturer in China. This project was set up in May 2020. During 17 months` developing, Roadtamer engineers overcame difficulties, improved processes, optimized coil spring parameter, and supported several customers' on-site testing. The product performance was finally highly praised by customer. This is the first time that Roadtamer entered ATV/UTV markets. Under the strong support of top management, Roadtamer established a CFMOTO production line to meet customer's demand. It is expected that the production capacity will reach 6000 pcs per month. Roadtamer will provide more competitive products with advanced technology to adapt more platforms, and increase more market share with excellent services in the future.

On September 28, 2021, China International Aviation & Aerospace Exhibition (Zhuhai Airshow) was held in Zhuhai, Guangdong. As a well-known brand in the shock absorber industry, Zhejiang Roadtameer Auto Parts Co., LTD will help the development of China's military industry and provide first-class chassis suspension solutions for the military and civil industrial transport equipment. Roadtamer adhering to the spirit of industry to serve the country, with our company's advanced technological achievements, first-class product solutions, all concentrated in Zhuhai Airshow. Our main products including: military truck shock absorber, war industry seat damper, refitted vehicle shock absorber, commercial vehicle chassis shock absorber, cab shock absorber, commercial vehicle seats damper, height adjustable damper, magnetorheological damper, electromagnetic valve control damper, etc. Our products attracted great attention from military suppliers and purchasers.Finally, welcome friends from all around the world come to Roadtamer booth No. H11B1-3 for more comunication. This exhibition is on a larger scale, and our booth attracts technical and procurement personnel from Academy of Chinese weapon science, Chongqing Tiemar China Science and Technology Group, Fangdun Technology and other groups. Roadtamer's technical and sales managers are busy with patient introductions and answers for all.

In order to implement the fire-fighting policy of "prevention first, combination defense and fire fighting", Roadtamer do a good job in the fire-fighting safety, enhance employees' fire-fighting awareness and protect the personal and property safety of the company and employees. Roadtamer carried out a fire drill on September 1 to ensure the fire safety of the enterprise. In the practical exercise stage, the firefighters explained how to use the fire extinguisher correctly and the precautions during use, and then everyone enthusiastically went to the battle to personally experience the "fire extinguishing". Through this drill, the emergency response ability of employees after a fire is improved, the proficiency of employees in the use of fire-fighting equipment is ensured, the fire safety awareness of employees is enhanced, and the fire safety of the our factory is improved.

On July 13th, we held the conclusion meeting of "Roadtamer Industrial Interconnection Project". Our Chairman Chen Bijun and Chairman Li Dong of Realtime Internet attended the meeting, which marked the official launch of the industrial Internet platform in Roadtamer. At the meeting, under the personal demonstration and explanation of Li Dong of Realtime Internet, all relevant departments understood the operation principle and rendering effect of the whole system platform. For the questions raised by the staff of each department, the team Litai Interconnection has made detailed answers. In the process of project launch, the company leadership attaches great importance to and actively cooperate with various departments, in force too interconnected technical personnel with the assistance of in accordance with the "overall planning and step-by-step implementation, easy to difficult, step by step after the first" principle. After the prophase research, data preparation, process, system test, simulation run, personnel training, such as phase, industrial platform into trial operation stage. Data-driven intelligent manufacturing The launch of the industrial Internet platform not only realized the information and integration of the production process data of Roadtamer, but also provided an effective way for the company to further realize the standardization of management and digitization of manufacturing, marking an important step for the company to "build a digital factory" goal.

Coilover shocks or coilovers are probably one of the hottest suspension components on the market today, but what is a coilover shock, how do they work, and what is the benefit to using them? To start, the idea of a coilover shock is pretty simple. A coil spring (or two or more as in dual-rate or triple-rate coilovers) is mounted through various methods to a shock or strut. The coil spring(s) support the weight of the vehicle and compress or extend as the vehicle goes over bumps. The shock dampens the action of the shock by controlling fluid movement, and this is usually where things get a bit more complicated. Within the shock's body, a piston rides on the shock shaft, moving up and down as the shock compresses and extends. On either side of this piston is a fluid, or shock oil. The compression and extension (rebound) of the shock is controlled by how much fluid can move through or sometimes around this piston. The rates of this fluid movement through the piston is controlled mainly by shims that control the valving. All these parts and exactly how they do their job can get complicated. So for now we will glaze over the finer details of shock valving to focus on the larger picture of how a coilover shock does what it does in general. We'll also talk about how it is set up, how it works, and why folks want them on their 4x4s. Coilovers Are Tunable The main benefit of an aftermarket coilover shock is they are rebuildable and tunable. By that we mean the end user can choose the shock travel length, choose from a wide variety of spring rates, and adjust the valving or how the shock dampens compression and extension (rebound). All these parts can be fine-tuned to do their job exactly as you want them to. That beats the pants off standard shocks and springs, which are generally aimed at some hypothetical middle-of-the-road version of your 4x4. That middle-of-the-road tune is not one for relatively light-weight or heavily loaded vehicles, but one somewhere in the middle. Not one for aggressive drivers or overly calm ones, but a hypothetical average driver. That works well for general suspension performance, but if you want to get the most out of how your suspension works for comfort on-road and off- you need to fine-tune it. That tuning isn't necessarily easy, but it's only possible if your shocks are tunable or rebuildable. To learn more, a lot more we recommend checking out the tech info on AccuTune Offroad. Coil Spring Rates Coil rates, or how much weight each coil spring can hold, is one of the easier things to tune on a coilover shock. Coil rate is usually measured in pounds per square inch and is determined by the wire diameter, how it's coiled (coil size), and a few other parameters. To get you in the ballpark, you need to know the amount of travel your shocks have and the corner weights of your 4x4. Corner weights can be estimated with existing coils, or you can get a front and rear vehicle weight at a truck stop with a scale and then divide that weight by two. You will also need to subtract the unsprung weight, namely the weight of the axle, wheels, tires, shocks (to get the sprung weight). Alternatively, a high-end fabrication shop or race shop should have scales that can give you very accurate corner weights (which can vary side to side). Once you have weight info and some parameters on how your suspension is set up (links, A-arms, trailing arms, etc. ), you can use an online calculator to get an estimate of coil rates, and a shock tuner or shock manufacturer should be able to get an idea of a good place to start with valving. Changing coil rates is as easy as unloading the shock, removing at least the lower-end spring retailer, and changing springs. The springs of course cost money but aren't too expensive relative to the full cost of coilover shocks. Some shock retailers and installers like AccuTune Offroad will calculate spring rates and valving for you when you buy coilovers from them or have them rebuild your shocks. SPONSORED CONTENT Capable Off-Road Tires that are Quiet and Durable? By Falken Tire Dual- Or Triple-Rate Coilovers Many coilover shocks have two (or more) coils on the body of the shock. These two coils ideally have different coil rates. The two coils push on each other via a coil slider, with the lighter coil compressing (on top) faster than the harder coil (on the bottom). That allows the suspension to be relatively soft until the softer coil reaches some level of compression. At this point the slider between the two coils stops at the dual-rate nut, and the shock jumps to the higher coil rate of the heavier coil spring. This point is adjusted by adjusting the dual-rate nuts that are threaded onto the body of the shock. Dual-rate springs help prevent hard bottoming and prevent a harsh ride, as the lower rate rides soft and the higher rate slows the suspension as the compression ramps up. Triple-rate coilovers are reserved for lighter-weight rigs where there is negative spring pre-load and the springs can be fully extended before the shock is fully extended. In this case a very light weight "tender" coil spring keeps the other springs from moving around when unloaded. Spring Preload Spring preload is set by lowering the adjusters on the top of the coilover shock to put the springs under a load without weight on the shock. Preload is set with the shock unloaded. Then the preload nut is tightened down until it touches the coil, holding it in place. That is the zero-preload setting. Preload is then added by tightening the preload nut down, compressing the spring. If you tighten the preload nut 1 inch and the spring is a 200-pound/inch spring, you've preloaded it 200 pounds. If you loosen the preload nut, then you have negative preload, which usually isn't a good idea except in some circumstances. Preload can affect the ride height of the vehicle to a small extent but isn't the main way that ride height is adjusted. If you need to add lots of preload to get the ride height you want, then you need higher-rate coils. If preload lifts the vehicle more than you want, you have springs with too high of a coil rate. If your shock tops out harshly, that could be because you have too much spring preload, and if the spring floats on the shock when unloaded, you don't have enough spring preload or require a spring tender coil. Damping As said, the damping properties of your shocks are set by valving of the piston. Generally, coilover shocks should have some dampening tuning to fine-tune the ride, but tuning the dampening is a bit more complicated than the other tuning we are talking about here. Like with spring rates, shock valving can be estimated based on your suspension setup and corner weights, but to quote a friend of ours, if your shock valving on a custom rig hasn't been tuned at least once, it isn't right. Chances are if your shock valving is off, you will need to learn a lot more about how shock valving works, or you'll have to bring in an expert like AccuTune Offroad to rebuild your shocks. For revalving, the shocks will need to be fully disassembled. Changes might be made to valving or coil rate based on how the vehicle works and what has worked for similar vehicles in the past. Keep in mind that each vehicle is different; very rarely will two custom-built rigs share the same exact spring rate and shock valving. Tuning is based on personal preference, vehicle weight, and driving style. This does become a bit easier on commonly built vehicles that use the basic OEM suspension design, but even in that situation, vehicle weight can fluctuate greatly. Gas Charging Coilover shocks come in at least three flavors of gas charging. First, emulsion shocks, where the oil is directly charged with nitrogen, the two are in the same chamber and can mix. Second, an IFP, or internal floating piston, where a floating piston (not the piston on the shaft) separates the oil from the nitrogen charge. And last, a remote-reservoir shock, where the remote reservoir has a floating piston that separates the shock oil from the nitrogen charge. Emulsion shocks are the least expensive and have the least amount of nitrogen, which requires higher pressures. Higher pressures mean more heat, and more heat is bad for a shock and performance. Also, the nitrogen and oil will mix, and both will pass through the piston, making damping inconsistent. IFP shocks are slightly more expensive but usually require a longer body for packaging the floating piston and nitrogen, again at a higher pressure. Emulsion and IFP shocks are usually not rebuildable. Remote reservoirs (and piggyback reservoir shocks) are more expensive, usually rebuildable, and generally work better off-road. They run cooler because there is more oil to absorb heat, and pressures can be lower because there is more space for the nitrogen in the reservoir. The main body of the shock in a remote-reservoir shock has only oil in it, with the reservoir containing both oil and the nitrogen (again separated by a floating piston). The amount of pressure added by the nitrogen also impacts how the shock works. Too much may cause a harsh ride (effectively adding spring rate), and too little may cause the seals to not seat properly (allowing leaks). Generally, the nitrogen pressure is set by the manufacturer. Anatomy Of A Coilover Shock Body: This seems obvious, but the body of most coilover shocks is the main part and is often threaded for adjusters. Shock shaft: This is the hard metal rod that moves in and out of the shock body. Shock shaft bumper: This is a rubber bumper that's designed to prevent damage to the shock if the shock compresses fully. You want the bump stops to prevent this from happening to completely avoid damage to the shock. Piston and valving: This is the part of the shock attached to the shock shaft that fits inside the body of the shock and controls fluid movement via valving. How these parts do exactly what they do is outside the scope of this article-it's complicated. But it is tunable for many of the larger remote-reservoir coilover shocks. Coils: These are the springs that support the weight, available in different spring rates usually in 50-pound/inch increments. Preload nut: This nut, or pair of nuts, sets the spring preload and fine-tunes ride height when the correct spring-rate springs are installed. Note that the preload is not the distance between the preload nut and the top of the shock, but rather the distance from zero-preload (nut snugged on the coils) to your preload setting, generally an inch or two below the zero-preload point. Dual rate nut: This nut, or pair of nuts, sets the stop point for the lower spring-rate spring on a dual-rate coilover. At this point the shock switches to a firmer spring rate, slowing compression. Sliders: The main slider is a plastic tube with a shoulder that holds the two coil springs together and slides over the body of the shock to play a role in the dual-rate function. Remote Reservoirs: A remotely placed reservoir for the oil, a floating piston, and the shocks' nitrogen charge. Compression adjuster: Some remote-reservoir coilover shocks have a compression adjuster available for fine-tuning the ride of the shocks. These generally don't work well for coarse adjustment on shocks that are not properly valved from the start.

The management of Roadtamer visited LITAl, the industrial digital benchmarking company. Mr.Lee, who is the president Lof Litai, introduced their line. Mr.Lee introduced "LITAI ManuGene" industrial Internet platform: using mobile phones to arrange production plans, realizing equipment monitoring on computers, quick feedback on abnormal production, displaying digital map on electronic plans, Kanban, etc. These core functions bring significant changes in management mode. The function of industrial Internet is to connect the upstream and downstream of the industrial chain vertically, connect the manufacturing industry and manufacturing service industry horizontally, complete transactions and Finance on the cloud, manage manufaturing and logistics under the cloud, and finally build an industrial complex. Roadtamer has introduced CSES-ERP system full module management. The next step is to build diqital product lines for high-levell customers, such as Daimler, MAN and Vibracoustic etc., to realize the whole process control in the production. Learning from this visiting, we have understood the innovation of digitalization and intellectualization that brought to the enterprise management mode. The future construction of the factory wil be transformed to manufacturing with diqitalization and Internet plus, and realize a new generation of intelligent manufacturing.

Roadtamer has introduces the Manugence ® Industrial Internet Platform (MG Platform). MG platform uses many advanced information technologies such as Industrial Internet of Things, Big data and Artificial Intelligence to realize data collection&statistic online, modeling and analysis, application development, resource scheduling, monitoring and management. Roadtamer will carry out digital production line in stages, such as arranging the production plan by mobile phone, monitoring the equipment on the computer, fast response on abnormal production, electronic Kanban, mobile phone work dispatching etc. Based on this line, we can achieve the whole process of production monitoring, fast decision-making, cost reduction and efficiency improvement. A new generation of intelligent manufacturing with Digital and "Internet plus" will be achieved in Roadtamer in the near future!

The United States developed the air suspension system during World War II specifically for heavy aircraft. The original purpose of air suspension was to save weight with a compact construction. Back then, air suspension systems were also used in other aircraft and some heavy trucks to achieve a self-leveling suspension. This would ultimately result in a vehicle with an axle height independent of the weight of a vehicle's cargo. Ultimately, the air suspension system offers several benefits and drawbacks for drivers who rely on larger trucks and vehicles to carry heavy loads. What Is an Air Suspension System? An air suspension system is a style of vehicle suspension that's powered by an electric pump or compressor that pumps air into flexible bellows that are typically made out of a textile-reinforced type of rubber. Additionally, Pro Car Mechanics describes air suspension as a replacement to the leaf suspension or coil spring system with airbags composed of polyurethane and rubber. A compressor inflates the bags to a certain pressure in order to behave like springs. Air suspension also differs from hydropneumatic suspension because it uses pressurized air instead of pressurized liquid. What's the Purpose of an Air Suspension System? In most cases, air suspension is used to achieve a smooth and constant driving quality, but in some instances, sports suspensions feature an air suspension system too. Similarly, air suspension replaces a conventional steel spring suspension in heavier vehicle applications, like trucks, tractor-trailers, passenger buses, and even passenger trains. Air suspension has also become popular in low-riding trucks like this gorgeous 1982 Dodge D200 Camper Special. What Is Electronically Controlled Air Suspension? According to the company now known as Dunlop Systems and Components, at the start of the 1990s, Dunlop developed and installed the Electronic Controlled Air Suspension (ECAS) system on the 1993 Range Rover Classic and again on the Range Rover P38A. The United Kingdom-based company developed the ECAS to include several key features: Vulcanized, heavy-duty rubber air springs at each of the vehicle's wheels An air compressor in the vehicle's trunk or under the hood of the vehicle A storage tank for compressed air, which allows you to store air at around an average of 150 PSI Valve blocks which direct air to the four springs from the storage reservoir through a set of solenoids, valves, and o-rings ECAS computer that communicates between the vehicle's main computer to calculate where to direct air pressure Air pipes connecting from the storage tank to the air springs that channel the flow of air throughout the suspension system A desiccant-filled drier canister to keep the internal recesses of the system dry The electronically controlled air suspension also features height sensors that are based on sensing resistance in contact with the terrain on all four of the vehicle's corners to provide height reference for all corners. Additionally, further advancements are beginning to feature some Electronic Control Units (ECUs) that are able to fit under the vehicle's floorboard, making air suspension more widely featured in everyday driving. The Benefits and Drawbacks of Air Suspension Systems According to Future Marketing Insights, the total value of the air suspension market at the end of 2017 was around $4.3 million. So whether it's a manual or electronic air suspension system, the benefits can greatly improve the ride of the vehicle. Take a look of some of the benefits of air suspension: More driver comfort due to the reduction in noise, harshness, and vibration on the road that can cause driver discomfort and fatigue Less wear and tear on the suspension system due to reduced harshness and vibration of heavy-duty driving Trailers last longer with air suspension because the system components don't take on as much vibration Air suspension reduces the tendency of short wheelbase trucks to bounce over rougher roads and terrain when the vehicle is empty Air suspension improves the ride height based on the load weight and a vehicle's speed Higher corner speeds due to air suspension being better suited to the surface of the road Air suspension increases the transport capabilities of trucks and trailers by providing a better grip that levels the entire suspension. An air suspension system can also be adjusted for feel, so drivers can choose between a softer feel for highway cruising or a harder ride for improved handling on more demanding roads. In the case of hauling heavy loads, air suspension offers more consistency and keeps all wheels even. The air suspension system keeps trucks level from side to side, especially in cases where cargo is difficult to level. This results in reduced body roll when turning corners and curves. Even with the benefits of an air suspension system, Driving Tests New Zealand suggests several drawbacks. Some of these disadvantages that so and so reports include: The initial costs of purchasing and installing an air suspension system - air suspension can also sometimes reach three times the cost in repairs as a leaf suspension system over 10 years' time Fuel overheads for running compressors for occasionally pumping air to the correct pressure Fuel efficiency can suffer from the heavier weight of air suspension over the weight of leaf suspension An air suspension system's vulnerability to air leaks can result in malfunctions Some of the drawbacks of air suspension systems are because of some of the mechanical issues they can be vulnerable to. Several of the common issues with air suspension systems that can require repair include: Rust or moisture damage from the inside that can lead to the air struts or bags to malfunction Failure of the air suspension tubing connecting the air struts or bags to the air system Air fitting failure resulting from initial fitting or infrequent use Compressor burn out due to air leaks in the springs or air struts from the compressor constantly engaging to maintain the proper air pressure Even with these common mechanical problems, the benefits can far outweigh the drawbacks.

More automotive manufacturers today are opting for the use of the continuously variable damping system called Continuous Damping Control (CDC) in their vehicles. It permanently monitors [influencing" factors, such as the road condition, load, vehicle body acceleration and driver`s actions. ByAndrew MarkelonMar 17, 2017 More automotive manufacturers today are opting for the use of the continuously variable damping system called Continuous Damping Control (CDC) in their vehicles. It permanently monitors [influencing" factors, such as the road condition, load, vehicle body acceleration and driver`s actions. The vehicle sensors register all of the changes. From this input, the control unit determines the optimal damping requirements. The proportional valve adapts the damping force in milliseconds for every wheel. This means better ride comfort and dynamics, less rolling and pitching motion and a shorter braking distance due to better road contact. These are advantages that are increasingly used in bus, coach, truck and agricultural machinery applications. Self-Diagnosis If there is an electrical or mechanical fault, the CDC damper must be checked just like a conventional damper and replaced if necessary. Even when you have to replace CDC dampers, no additional work on the electrics is required. In order to remove the CDC dampers, you only have to disconnect the plug from the wiring harness of the proportional damper valve and reconnect it during installation. The CDC system is capable of performing a self-diagnosis, but it recognizes only electrical faults, not mechanical malfunctions. In the case of a fault, the CDC control lamp on the dashboard lights up. To narrow down the problem, a diagnosis unit is required, which can be used to read out and delete the error memory. Depending on the vehicle, it is also possible to compare the target/actual values in order to check the sensors of the CDC system. CDC dampers must always be replaced in pairs. To guarantee full functionality, the add-on parts - impact stops, protection tubes and suspension strut mounts - must also be checked for wear before assembling the dampers. Every time the dampers are replaced, the service kit consisting of the protection tube and impact stop must also be exchanged. Stressless Installation Tension or strain on the dampers can be avoided by tightening the lower fastening screws only when the vehicle is standing on its wheels. After that, the wheel geometry is measured and readjusted, if necessary. After every CDC damper change that is carried out per axle, the system functions need to be checked. When the ignition is switched on, the CDC control lamp must go out after approximately 10 seconds. The CDC damper system will now be ready for use.

When pulling together all the components for a kit car, a buyer has to make myriad decisions on the quality versus the price of each part. This is the only way to build a car that has the owner/builder's stamp on it, restricted, perhaps, by part availability and price versus the overall impact that part will have on the finished project. This process holds true with regard to shock absorbers--it is a choice made depending on price, quality, and what you want it to accomplish vis-a-vis what you want your car to do. For the last five years, the shock absorber has grabbed the headlines as the hottest way to tune a car's suspension. From all the attention the shock is getting, you would think that it is the most important part on the car when it comes to handling. It is not. Our English friends call a shock absorber a dampener, which may be a better name, because its job is to dampen the oscillation of the spring. The spring controls and absorbs road shock and vehicle weight transfer, not the shocks. The spring controls the up and down movement of the tire as it goes over undulations in the road. The spring also controls the movement of body roll or weight transfer as the car makes transitions from left to right turns and from front to rear braking and acceleration. The shock absorber controls the speed that weight is transferred in a car, not the amount of weight transferred. It also controls how quickly the wheel settles back on the road after hitting a pothole. Hydraulic Pressure A shock uses hydraulic pressure to dampen the oscillation of the spring in a controlled and timely manner. The shock resists the spring's movement by forcing oil through a series of valves, orifices, and blow-off plates in the shock's piston. How much and at what velocity the oil is allowed to pass through the piston and valves determines the dampening characteristics of the shock. SPONSORED CONTENT Four Wires to EFI! The Easiest Way to Add EFI and Ignition Control... By Holley Performance A shock absorber must dampen the movement of the wheel and the chassis at different speeds. When driving a vehicle on a smooth stretch of pavement, there is very little up-and-down movement of the wheel. Therefore, the piston inside the shock has very little velocity or movement. As the speed of the car increases and potholes or speed bumps are encountered, the piston shaft must move quicker. Shock manufacturers must develop shocks that have the correct valving to handle both extremes of shock travel. Every shock made is a compromise between ride comfort and performance. Some shocks are valved for more comfort and offer a Cadillac ride. Other shocks have firmer valving and give a more performance feel. Valving Characteristics A shock absorber uses different valves and springs to adjust the dampening force of that particular shock. There are three types of valving characteristics that dictate how the shock will perform. They are progressive, linear, and digressive. Progressive shocks start out soft and get stiffer quickly as the shaft speed increases. Linear shocks uniformly increase stiffness as the piston speed increases. It is similar to the progressive valving but does not make dramatic changes at higher speeds. Digressive is just the opposite of progressive. It starts out stiff, then it tapers off. A progressively valved shock generally will produce a better ride quality, because the shock is softer at slower piston speeds. A digressive shock offers a harsher ride because it is stiffer at slower speeds. The advantage to a digressively valved shock is vehicle control. It offers more stability because it takes a lot of the body roll out of the car, which enhances the corning ability of the vehicle. Linear valving is predictable. It starts off soft and gradually gets stiffer as the piston speed increases. The ride quality and car control will be average. Several of the shock absorber manufacturers offer adjustable shocks. The customer can adjust the rebound and compression dampening qualities on a double-adjustable shock. While on a single-adjustable shock, normally just the rebound is adjustable. An adjustable shock offers a number of benefits. First, if the spring sages or loses rate, the shock's compression can be increased to add stiffness to the ride and make up for lost spring rate. Secondly, if you install stiffer springs, there is no need to buy a new shock. The rebound dampening ability of the existing adjustable shock can be tuned to control the extra energy of the new spring. As the spring rate goes up, you need more rebound dampening to control the greater capability of the higher rate spring. The third reason for adjustable shocks is the ability to tune the suspension. You can change the ride and performance characteristics of the vehicle by turning the adjustor on the shock. Remember the spring rate is the most important thing in changing a suspension's handling characteristics. The shock is a fine-tuning tool. Mono- vs. Twin-Tube There are three different types of shock absorbers: mono-tube, high-pressure gas; twin-tube, low-pressure gas; and straight-hydraulic, twin-tube. Each has advantages and disadvantages. It is impossible to say that one design is the best in all applications. A properly valved mono-tube shock will work as well as a properly valved twin-tube shock. The bottom line is the spring does not know what style shock is controlling it. Another area of personal preference is the use of coilover shocks. The major advantage to coilovers is the ability to easily change the car's ride height. With larger 5 1/2 -inch springs, you must use spacers or buy different-size springs to vary the ride height. Never cut a spring to lower the car. It will change the spring rate to an unknown value and complicates the tuning procedure. Because of its small size and lighter weight, a coilover may be a benefit for high-performance vehicles. You also have a better choice of spring rates available with a coilover. With big 5 1/2-inch springs, generally the spring rates are in 50- and 100-pound increments. The spring increments for coilovers are generally 25 pounds. Coilover shocks are available in twin-tube and mono-tube designs. Stock Shocks Before talking about changing out the stock absorbers that came with your kit, it would be prudent to examine what some of the top builders include with their cars. Shell Valley primarily uses its own patented shock absorber called the "Silver Bullet." They CNC the outer billet aluminum housing and insert a Monroe gas shock absorber. They picked a little stiffer shock to match the performance they wanted in the car. The ride height is adjustable, but the valving is not adjustable. Rich Anderson, the owner of Shell Valley, told us, "We can make our own shock cheaper than can we can buy a coilover. It is a lower-cost alternative to some of the adjustable shocks and still gives us the performance we wanted. If someone wants another alterative, we supply an Aldan coilover shock with the adjustable valving on the bearing end. It is adjustable for compression only. The Aldan shock link matched our shock link and the spring we use works on that shock. We use the same shock on all our kits because the chassis is basically the same. We either just lengthen or lower the middle of the frame." For tuning and ride purposes, Shell Valley has different spring packages available. They are all 10-inch springs. In the front, you can have 350-, 450- or 550-pound springs depending on the size of your engine. In the rear, it will be either a 250- or 300-pound spring. The weight difference between a big-block and a small-block will dictate the basic spring package. If you are going to run on a road course and be turning hard, you want a stiffer spring. For the Cadillac ride, you will want the softer spring. At Factory 5, they use Pro shocks on their spec racers and are now switching over to Bilstein shocks on the street cars. Pro is a very good, inexpensive racing shock used primarily in circle track racing, so you know they are durable. Jim Schenck, head engineer at Factory 5 Racing, said they switched to Bilstein because, "They are the best mono-tube shock we could get at a reasonable price. The Bilstein mono-tube shock is on the same level as a Koni or other high-end shock. A big thing with our kit is the price. It is one of our selling points. If we can offer better parts for the same price, we are going to do it. I have driven the car with the Bilstein shocks and there is a handling improvement without a detriment in ride quality. The Bilstein shock is not adjustable. They are making a shock specifically for us. We didn't want to change the geometry of our suspension and they didn't really have anything that fit our car that was compact enough in size to fit into the chassis and had enough travel." Three Spring Rates Schenck said, "We use different spring rates based on engine choice and whether it is a street car or a spec car. The standard front spring for a small-block is 450 pounds, for the big-block it is 500 pounds, and the spec racer is a 600-pound spring in the front. We don't change the valving of the shock for the small-block or big-block, but we do change both rebound and compression for the spec racer. "We didn't go with an adjustable shock because of the cost. Most people use the spring rates we offer and wouldn't be able to tune the shock to the springs and get a combination that works well. For most people, it is easier for us to do the work for them rather than have them figure out what adjustments to put on the shock. We work with shock companies and compare shocks back-to-back in order to see what valving works the best." Gary Stowe, technical director at Street Beasts, told us, "Like a lot of the other manufacturers, our kits are relatively generic in the sense that they are engineered to use readily available OEM parts. If a customer chooses to use a version of the Mustang II front suspension or an 8.8-inch Ford rearend out of a Mustang, our shocks and springs are pretty much equivalent to a heavy-duty or upgraded OEM suspension component. "For the person who wants to build a Pro Street car out of one of our kits, we developed some very specific suspension packages. We use a special frontend and an Alston Fab 9 housing for the rearend that we finish in-house that will accept up to a 20-inch-wide rear tire. It is a narrowed rearend in a four-link setup with Carrera coilover shocks. With those specific packages, I have been working very closely with Ben Abernathy at Carrera. We have developed with them some very specific-length and special-valving shocks for our application." As with most kit car companies, Street Beasts changes its spring and shock package depending on the engine combination used. A smaller block in their '34 coupe would use a 425- or 450-pound-per-inch spring, while a big-block would use a 525- or 550-pounder. The shock is subject to 200 pounds of extra weight over the front axle because of the big-block engine. How To Koni Shocks are known worldwide for their racing double-adjustable shocks. They also make high-performance single-adjustable shocks for street use. Koni Sales Manager Lee Grimes told us how someone would go about upgrading the shocks on his car. He said, "It is really quite easy. The first thing we will ask is how he uses the car. Is it a daily driver, a Sunday car, a cruise car, or is it a lapping day car? Cobras and other kits are getting more popular for going out on racetracks. The next question is: What is his budget and is he looking for a coilover or non-coilover shock? From that point, we talk about dimensional requirements. If he already has a car on the road, he can use the front and rear dampeners he is using as a point of reference. We ask him to take some measurements on the car. We will find out what the attachment points are. "Are they spherical bearings, rubber eyes, or pin-style mounts? We will have them take a measurement of the shock on the car from the lower mount to the upper mount at static ride height. Then we will check his current shock and see where it is in relationship to its maximum extension and compression. For example, if the car sits at 16 inches of static ride height, then we want to make sure that is about the middle of the overall stroke range. If the shock's stroke turns out to be 22 inches extended and 15 inches compressed, obviously he is almost bottomed out. We suggest a shock length that puts your static ride height needs toward the middle of the shock's overall range. Then once we have something that will physically bolt to the car and be in the right stroke ballpark, we will talk about what spring rates he running. Then we can select the valving for his use." Everything Koni makes is either single- or double-adjustable. We asked Grimes if a kit car builder needs an adjustable shock when most probably won't crawl under the car and play with the adjustment. He responded, "I disagree a little bit. You have a guy who has a Manx dune buggy. Yes, he is going to be in a budget range and not going to be adjusting his shocks. On the other hand, there are a number of Cobras and other cars that go to the track. For these guys, an adjustable shock is important." An adjustable shock could be a benefit if your car serves a dual purpose of being a weekend plaything and a twice-a-year race car. Being able to stiffen the shocks for the on-track days and soften it for daily use would be valuable. New Idea Edelbrock has come up with a different way to valve their Performer IAS (Inertia Active System) shock absorber. Their shock engineer Dave Shirley explained how it works. "This is the first shock that differentiates the wheel motion and chassis motion on rebound. We have come up with a way to break up the two different motions. You can extend the shock two ways. The wheel can go down and the chassis can go up. That is two very different requirements. When the chassis is going up, you have 4,000 or 5,000 pounds trying to pull up in a slow motion. You need lots of dampening load. When the wheel wants to go down, you have a 100-pound item trying to accelerate 10 times the speed of the chassis. We have a shock that can tell the difference. As the wheel pulls on the shock, it opens up some bypasses, get softer, and allows the wheel to move at the speed the wheel wants to move. Because we can do that, we can increase the dampening to control chassis motion. The shock is firmer and defaults soft if it hits wheel motion. I am talking about rebound only, forget about compression. At slow speeds, the inertia valve will stay closed. At higher wheel speeds the valve will open to make a softer shock. "A conventional shock has a valve stack on rebound and a valve stack on compression. We have a valve stack on compression, and on rebound, we have two valve stacks and a means to bypass one of them. The inertia valve is opening and closing ports allowing the oil to free-flow as the wheel accelerates down." The Right Shock You know you have enough rebound dampening in a performance street vehicle when the car goes through one complete suspension cycle and settles. For instance, when you hit a bump, the shock compresses, then extends, then comes back to ride height. That is one cycle. If the car continues to bounce or goes through another cycle, you need to add more rebound dampening to the shock. Most street rods or kit cars are over-sprung. All the manufacturers are building more rebound than compression dampening into their shocks, because as the spring compresses, it gets stiffer. The shock does not or cannot control that movement effectively. It is more important to control all of the compressed energy as the spring rebounds. The theory is to let the spring do the compression work and let the shock take care of the transition from bump to rebound. Tech expert Pat LaValle at QA1 told us, "Shocks are often sprung incorrectly because 90 percent of the street rod builders have never taken the time to get the car on scales to figure out weight and where the car's weight bias is. Is it 60 percent up front when you think it is 40 percent? You need to spring correctly front-to-back and use a four-corner scale to be accurate. Choosing a shock depends on which valving you'd like and which use you have designated. Is your car being shocked for road racing or the street. It is best to consult your shock guy or the manufacturer's tech line." It's your car, your shock, your usage, and your choice...but that's part of the fun of the project, isn't it?