How to Build 4-Link Bars
Feb 06, · In this video i setup a Upper triangulated four link kit on the Jeep Wrangler TJ. I used the Barnes 4WD 4 link kit for this long arm suspension build. I. Download a 4-LInk Calculator. The first step in either building a 4-link suspension or troubleshooting an existing suspension is to download one of these Triaged calculators created by Dan Barcroft and plug in the dimensions and weights it asks for.
One of the most common questions we get about suspension setup and tuning is how 4-link geometry affects the performance and handling of a vehicle. In this article we'll cover what we consider to be the three most important elements: anti-squat, anti-dive, and roll center. When building a 4-link suspension, the lengths of the links, their positioning, and the angles at which they are mounted, will all determine how the suspension affects the vehicle chassis under acceleration, braking, and cornering.
While a chassis with too much body roll can easily be improved with the addition of a properly tuned sway bar, undesirable rear squat and front nose dive characteristics can only be fixed be changing the 4-link geometry. These unwanted characteristics are caused by incorrect 4-link geometry and they can only be improved by changing that geometry. Don't Over-Think It: There are many thick how to make waterproof bag, expensive software, and hundred-page internet forums out 4c4 on the subject of 4-link geometry and it is very easy to get lost and frustrated.
You are not building a Formula 1 racecar so don't expect to be plotting the movement of your suspension under every posible situation. The best advice we can give is to not over-think it, as long as you are familiar with the basic concepts of anti-squat, anti-dive, and roll center, and the axles move nice and smooth when you cylce the suspension, you will be in great shape. The first step in either building a 4-link suspension or troubleshooting an existing suspension is to download one of these 44 calculators created by Dan Barcroft and plug in the dimensions and weights it asks for.
While they may look complicated, they are actually very easy to learn by just entering numbers and watching the outputs and graphics change. Anti-squat in a linked suspension system determines how the rear end of a vehicle moves under acceleration or upon the rear axle contacting an obstacle at speed.
The anti-squat value is determined by the vertical angle of lino rear links as they relate to the front axle position and the center of gravity of the vehicle. These characteristics are sispension for drag what is the vehicle id number and heavy acceleration applications because the forces that push the rear end up also push the rear tires down for more traction.
At speed, however, when the rear tires impact an object, that immediate increase in traction will cause the power applied to the rear axle to raise the chassis up at the same time as the suspension is trying to compress and absorb the impact. These characteristics are desired for desert racing to absorb rough terrain at speed because the impact forces are transferred directly to the rear suspension. Under hard acceleration, however, some of the power applied to the rear axle is used to compress the rear suspension which lifts up on the tires and robs traction and power.
These characteristics make the vehicle neutral and keep the power and suspension dynamics independent. Anti-dive geometry in a linked suspension system determines how the front end of a vehicle moves under braking and acceleration. The anti-dive value is determined by the vertical angle of the front links as they relate to the rear axle position and the center of gravity of the vehicle. Under hard hkw, high anti-dive geometry will cause the suspension to compress, thus keeping the front end down and under tension which is desired for steep hill climbs.
As a trade-off, a suspension system with a high anti-dive setup with be less able to absorb rough terrain under hard braking as is required by rally cars and short course trucks. Under acceleration, a low anti-dive geometry will cause the front end to lift and the suspension suspendion extend which also shifts weight to the rear of the vehicle. These characteristics are great for aggressive driving on hard packed dirt tracks and hill climb racing.
Many mud-drag racing vehicles use low anti-dive geometry to shift weight to the rear axle under acceleration and extend the front suspension to better absorb the terrain. Supension, vehicle's with low anti-dive suspension geometry may how to keep an aries man in love excessive 4c4 under hard braking. The roll axis and roll center of a vehicle's suspension system determin how much body roll or sway the vehicle will experience when cornering.
The roll axis is the imaginary line drawn between the two points made where the lower links would eventually connect and suspensiin the upper links would eventually connect. In the case of a suspension with 4c4 links the roll axis line is simply going to be parallel with the parallel links. The point along the roll axis that is directly above the axle center line is the roll center. The distance between the roll center and vehicle's center of gravity becomes the leverage factor for body roll.
In other words, the further above the roll center the vehicle's center of gravity is, the more body roll the vehicle will experience during a turn. The closer the roll center is to the center of gravity, the less body roll the vehicle will experience and, in theory, if the roll center is on the center of gravity line, the vehicle would have no body roll. One additional note about the roll center is that while the center of gravity of the vehicle always remains the same in relation to the chassis, the roll center and roll axis how to build 4x4 4 link suspension move as the suspension cycles.
For most applications this change in roll axis is not worth considering and the calculations should be done at ride height.
For racing applications, however, watching the roll axis as the suspension compresses entering a hard turn may be worthwhile. Finally, unlike anti-squat and anti-dive that can only be tuned by adjusting the 4-link geometry, a vehicle with too much body roll can easily be improved by installing a properly tuned sway bar without negatively impacting ride quality or suspension performance. Crawlpedia is proudly supported by Filthy Motorsports ro, a specialty off-road racing and 4x4 parts shop in Boulder, Colorado.
Want to see your banners and links on Crawlpedia? It's easy, affordable and very effective, just contact us to get started! To find the street legal laws for your state including maximum suspension lift heights and tire size rules visit LiftLaws. Filthy Motorsports Crawlpedia is proudly supported by Filthy Motorsportsa specialty off-road racing and 4x4 parts shop in Boulder, Colorado.
Advertise Here! Street Legal Laws To find the street legal laws for your state including maximum suspension lift heights and tire size rules visit LiftLaws.
Parallel 4 Link Rear Suspension System
Jul 06, · Barnes 4wd should have the custom off-road parts you need to fabricate a four link system on most 4x4 vehicles. Additional Off-road Parts If you’d rather put together your own 4-link suspension system, you can customize your selection of Shock Brackets, Tabs, and Towers, DOM Tubing, and all of the other necessary heavy-duty suspension parts. ” total threaded length ” minimum threaded into tube ” thick jam nut” is the maximum thread sticking out from the jam nut allowed, and still have” threaded inside the tube”/” is the middle of the adjustment range. Here you can see the finished 4-link bar with the rod end adjusted to the middle of the allowable stick out. Aug 17, · -Lastly build strong brackets, especially at the chassis and convergence of the tri link or wishbone. That will give you a good start. This is by no means the be all end oll of building a link suspension I probably left out a ton of stuff. Look at a lot of different suspensions and you will .
A newer style that works well as an all-around type of suspension and also does great on the track. This is a 4 link suspension with all 4 links running parallel to each other.
This kind of suspension always has some kind of panhard bar to keep the axle centered. The parallel 4 link is designed to keep the rear axle centered, and to keep the pinion angle from changing keep the axle from rotating.
It works especially well under hard acceleration at the drags or hard cornering at the track. Check out Tuning 4 Link Rear Suspensions for the Drag Strip Advantages : This style of suspension works well for an everyday driver and also works well on the track. This type of suspension can also be made to have adustable anti-squat geometry for the drag strip and the long Panhard rod really controls the rear axle's side to side movement to help in hard cornering.
Disadvantages : 4 links designed for the drag strip don't work well on a road course, and may not ride well on the street. Extreme cornering can lead to some roll bind, due to it's geometry. Changing out the bushings to Heim joints or urethane bushings will usually cure it though. Another disadvantage if you are going to swap in a parallel 4 link is difficulty and cost. You will also need to have some welding and fabrication skills. Well, you don't really You can lower it a little bit with lowered springs, but if you lower it too much you will change the angle of the 4 links.
This can affect how the suspension handles. If you want to lower it a lot for ride height, you will have to raise the mounting points where the 4 links attach to the frame. Some people do use this system for an air bag suspension so they can drop the frame on the ground. However, at ride height you still need the 4 links at the correct angles. Ok, so how do I lower my ride with a parallel 4 link system?