Your email address will not be published. Thanks so much! It comes with a locking bolt to tighten the bushing. If you have a Fox-body or SN95 Mustang, a 1980s GM G-body (Grand National, Malibu, El Camino, etc.) $15.75. Matt, But since left side Adjust the length of the control arms as needed to achieve the desired pinion angle. very stiff. Add a good weld-on ARB out back. Anytime you are acting thru an angle, this force is diminished and is not as effective as it could be. NOTE: If installing on a Frankland quick change, the bracket will need to be modified and reinforced to fit. You should draw the paths to include Wehrs Body Bolt Panel Inserts. Leaf-Spring Systems - The leaf-spring rear suspension system locates the rear-end fore and aft, as well as laterally using the leafs. Advance Design Trucks seem to be using rear ends with widths ranging from 58"- 62". Adjustable trailing arms will allow you to set the static pinion angle. Or if you wish to keep your Edelbrock uppers, then just purchase a set of adjustable lowers (again, I prefer the double adjustable configurations theyre easy to tune in the car). Add to cart Details. ance with altitude u p to the equilibrium line. change. $149.99; 149 - Reward points. Because there is very little slip of the tires on asphalt, the range of useable rear steer is very small. Another component that promotes rear steer is when the rear trailing arms are angled from a top view, with the front mount closer to the centerline than the rear mounts. shortened bottom link. Youll find that an instant location similar to stock is actually close to optimum, provided you dont jack the body way up in the air. This saves wear and tear on your U-joints while . Wayne thanks for the input Soft springs, a left chassis-mounted track bar, and easy-up shocks on the left side all promote the body roll that produces rear steer to the right. Justin is the owner of High Roller Race Cars. This will give you a lower rear roll center and aide side bite. That saved the factory some money. Again the height of the mounts are critical as to the resultant force transmitted. AA-621-D is a clamp-on spring cup, fitting 3 tubing $24.95. These arms are longer then stock to help lessen pinion angle changing during suspension travel. springs). article to determine the correct link lengths for your application. Copyright Racelogic Chassis School 2023. The amount of rear steer due to body roll is regulated by the height of the front mounts of the arms, which are always mounted lower than the rear point of rotation (the axle). My lower trailing arm is level. forward (See illustration 1). (on a clamp bracket) generally tightens corner handling. Conversely anti-dive is used to describe how much a chassis nose dives under braking. One disadvantage is pointed out by Masters. One fix is to position the links so that the LR bracket is 6.75 from axle tube to center of bottom hole. The rear semi-trailing arm suspension is an independent rear suspension system similar to the pure trailing arm suspension, with the primary difference being that the bushing axis (or instant axis) runs at an angle in all X, Y, and Z directions. links have to be extremely short to minimize loose roll steer. All we had to do now was work on consistency. 1/2" on RF (5 degree angle of Upper A-Frame mounting bolts), 1/4" on LF, front higher than back, average bolt height the same as before. The upper trailing arm mounts (part No. Instead of using some form of track locator or Watts linkage, the trailing arm triangluation keeps the rear end properly located in the car. If you dont do anythinig else. the bottom of the birdcage now moves rearward (until the link reaches a level Any of you guys changed any angles on trailing arms etc on a metric to make it faster? It uses four links, as the name implies, that are not parallel to the centerline of the car. A racer himself, he was the winner of the Street Stock Nationals in 2019. Use this kit to build your own custom rear end. The sideways attitude of the car does two things: 1) it helps to slow the car down on entry much like an air brake on a Lear jet, allowing deeper entry and 2) it may also help to produce a left-side, lateral force that resists the opposite centrifugal force that tries to take the car to the fence. 2,224. 3 to 4 degrees nose-down is recommended. These conditions call for a driving line that is more straight ahead. made to provide such handling, you must first understand a few basics (more on this later). right, the left rear tire can become loaded more quickly than the right This induces less rear steer when the car squats on exit. There are a few similarities, but many differences in how we evaluate and use rear steer for each group. That gray-colored bar that goes up from the forward trailing arm mount is an aftermarket mounting brace that ties the upper and lower mounting points together. Rayburn builds the swing-arm type of rear suspension. Heres a look at an adjustable upper trailing arm fitted to a GM G-body. suspension). gained by running the trailing arms upward to the front of the race car. A smooth entry provides a faster exit. link lengths and angles and how the relationship affects roll steer and However, A 4-link When you add more horsepower, bigger and stickier tires, and start pushing the car, then the flex in these arms becomes even more apparent. note the left rear tire moves to the front in body roll. For example, you want the top link to be perpendicular to the rear end housing and parallel to the car. Keep in mind that trailing arm angles can become excessive if the rear of the chassis lifts a lot during acceleration. Wehrs Bent Suspension Tubes 5/8"-18 Thread. You can evaluate the roll steer characteristics of different set-ups When using trailing arm angles to help your setup it pays to truly understand the movements at each section of the corner as well as think about any drawbacks that rear steer or understeer might create. With adjustable trailing arms (rather than the factory originals), you can adjust the pinion angle by simply changing the length of the upper trailing arm. . This clamp on trailing arm mount is for the GM metric chassis lower bars. 2.50 from axle tube to center of hole. C.J. During chassis roll, trailing arm/s mounted upwards will cause the right shorter than the upper links) work best for fast tracks or on any track and parallel to each other). #2. pat the angle of the trailing arm wont really effect anything that much. Heres a better look at a trailing arm mounting brace. Wehrs Body Braces. Up To 50% Off Prices EveryDay! everything is a compromise. As the rear end rocks back under acceleration the angle in the arms are trying to lift the chassis in front and therefore pushes down on the rearend housing in the back. Oct 12, 2013 #2. If the car has OEM style rubber suspension bushings, a pinion angle of minus three to minus four degrees is more appropriate. To make it work, Id be inclined to either use spherical bearing upper and lower rear trailing (control) arms or at least a set with Delrin bushings. abbreviation Loss of t h e final ontogenetic stages during the a b l a t i o n m o r a i n e An uneven pile or continuous . You should keep in mind that any loading of the rear tires caused by Any angle up hill to the right rear will cause upward force on both tires and unload both tires. clamp brackets are used in front of the axle, axle wrap-up during Simply replace the slug with different combination of offset slugs. Trailing arm bushings come included (part No. Usually, the right-rear corner of the chassis moves more than the left-rear. 2- 175-C bushing for upper mounts. In Stock . AA-175-C). We do not necessarily need to know the exact amounts of rear steer our cars are subjected to, but we do need to have a solid understanding of what produces rear steer and what effect rear steer has on the handling in our cars. of the This was encouraging. Since then, hes been a columnist, writer, and photographer, in racing and in mainstream media, for several outlets, including the Journal Inquirer, Boston Herald, Stock Car Racing, and Speedway Illustrated. The company offers a wide array of quality chassis components at reasonable prices. front of the The stock trailing arm mounting kit (part No. race car. Followed your advice and got a set of adjustable lowers. To see if rear steer is an important tuning tool, we turned to some experts. Custom Part is Non-Returnable and Non-Refundable. 4. One of the reasons a car will test fast in practice, qualifying, and maybe the heat races, but then be out to lunch when the track changes come feature time, is a result of improper rear steer. illustration 2A. The Standard 4-Bar System birdcages and mounted to The Asphalt 3-Link - The 3-link rear suspension system has two trailing arms mounted near the rear tires, and one third link mounted atop the rear differential that controls rear end wrap-up. (Steel). Undo the two bolts that hold the subframe support arm: the rear of the arm bolts to the front of the rear subframe, and the front of the arm bolts to the trailing arm bracket. coil-over units on The A & A Manufacturing stock trailing arm mounting kit (part No. are used to help control loose steer. what wold be the best angles to be at for most foward bite along with handling four all four links ? This caliper mount brackets is built to fit the small GM metric calipers. It helps prevent the mounting points from tearing out when the suspension is shocked during a starting line launch. With so much movement, we can plan out our rear steer just about any way we need it. Other teams may just stick with a fixed location for the mounts in the rear end and adjust handling with other means. If we mount the left-side trailing arm lower than the right-side trailing arm, then as the rear end rotates under acceleration due to the pull bar extending, the left-rear wheel will move rearward more so than the right-rear wheel, causing rear steer to the left to a small degree. Mounting both Wayne The layout, lengths, and angles of the upper A-Arm work together with Lower Control Arm to encompass what engineers refer to as an Instant Center. (USRA/IMCA Stock Car Legal). Im converting a Pro-Challenge car for road racing, ad Id like to get rid of the Panhard bar, and go to triangulated upper links. These new Superior 28 or 31-spline axles feature screw in studs in a 55 wheel bolt pattern, , thick heavy duty bearing retainer plates, and tapered wheel bearings pressed on. On asphalt, do not make large changes to components that influence rear steer. Wehrs Modified Valance Support Weld On Clevis. Owner-operator at Race Products Inc. suspension. the bottom of the Some manufacturers have added multiple mounting points on the front and rear chassis mounts. AA-621-C is an offset spring cup, which sits 2-1/2 off center of a 3 axle tube $14.95. A trick way to produce rear steer only under acceleration is by staggering the height of the two trailing arms in the 3-link system when using a pull bar, upper-third link. Under the right conditions, rear steer can be beneficial and enhance performance. Excess loading of either the left- or right-rear tires decreases traction in most cases. Notice, in illustration 2D, Another option are the double adjustable UMI upper and lowers available at Summit Racing (Part Number 402717-B or 402717-R). . Made out of 1/2 thick steel to gain extra LR weight. Jul 23, 2001. * upper control arm angled down from ball joint to pivot at 1.4 degrees. If you are racing on a rough track or up against the cushion you will need these bushing washers to help hold the rubber from pushing out the end of the bushing housing. Designed for the Wissota street stocks, these trailing arm brackets have the lowest mounting hole position possible. KT-1A). We can have too much weight end up on the left-rear tire and lose traction and/or cause the car to push off the corners because of all of the forward thrust is concentrated in the left-rear tire. When one wheel moves more than the other, we have a certain amount of rear steer. Typically, indexing causes the coil-over mounts, if located on the Semi-trailing arm suspension, handling and stability performance, non-linear vehicle model, Bees algorithm Date received: 17 November 2011; accepted: 3 February 2012 Introduction am out of adjustment on the uppers so will be installing a set of adjustable lowers KT-1B) sells for $96.00. Since drive line angles can change if you adjust your ride height, your pinion angle may need to be adjusted. by running the trailing arms upward towards the front. When Suspension Type Camber Angle; FWD: Multilink Trailing Arm Twist Beam: 1.0 1.0 1.0 RWD: Multilink Trailing Arm Swing Arm: 1.0 1.0 1.3 AWD: Multilink Double Wishbone Trailing Arm: 1.0 1.0 1.0 4WD: Multilink Double Wishbone Trailing Arm: 0.5 0.5 0.5 (during acceleration) is quickened and forward bite is enhanced. That can work for a mild street or bracket car, but will make a high-horsepower car react violently at launch. movements of the about rear suspensions. . Street Stock. These stamped metric style control arms are great replacements for twisted or worn out rear upper arms on your GM G-Body. starting point for both links is 15 upwards (to the front). 2). Specialize in complete bushing overhauls and suspension upgrades to enhance the driving experience for your Mazda RX-7, Mazda RX-8, and Classic Mazdas (R100, RX-2, RX-3) but are more than capable of servicing all cars with the same care and attention to detail. . The rear semi-trailing arm suspension combines the advantages of the trailing arm and double-pivot swing axle suspension principles, without the . After subframe support arm is out of the way, unscrew the . right side positioned ahead of the axle and attached to A drag race style anti-roll bar is a key ingredient to making your triangulated four-link work. 4AN To for 8mm X 1.0 Metric Straight Adapter Vibrant. Some will say run them as low to the rearend housing as you can. Lower the front LR trailing arm mount. These tapered profile spring cups are manufactured from high strength steel and are designed to minimize any stretch and bending while still being lightweight. I am settling 1100 hp LS Irwin turbocharged in it. of a 4 link suspension are the link lengths designed into the suspension $64.00. The Truck-Arm System - The truck-arm system has been adapted from the design for a 1964 Chevy truck, and is used on many Late Model Stock cars, as well as the three premier divisions of NASCAR (Craftsman Trucks, Busch, and Winston Cup). with the very soft chassis meaning floppy front subframe is 4.5 enough? During chassis roll, indexing loads the right rear tire and unloads The lower links are angled from a top view with the front pivots narrower than the rear pivots. birdcages, to rotate against the shocks and springs during These trailing arms will improve handling of the rear suspension by replacing either twisted or worn out OE control arms. Rear steer amounts-due to the Panhard bar angle-are regulated by the angle. Bad shocks (and/or messed up valving) can be the culprit. Perfect for the guys that already have or Extreme or Xtrmer Drop brackets. He will be showing the latest tools to enhance your chassis set up. Spring Perchs & Brake Caliper Brackets are now Bolt-On Accessories (not included in Rear End Housing Price). how the shortened bottom link pulls the bottom of the right side Those cars have multiple holes, allowing the angles of the control links to be altered to produce more or less rear steer. - Trailing Arm Brackets - Bushings in Upper Mounts - Brake Caliper Mounts (GM Metric) .