it feels as a plank over nude bearings on the road .. Indexing is greatest when there is a lot of A rear end steered to the left of centerline will cause the thrust angle to be left of centerline and make the car tighter on entry and tighter on exit under acceleration. In this case, that equates to a 10.80. JavaScript is disabled. AA-175-D. There are times when we definitely want the rear to steer to the right. 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). Excess loading of either the left- or right-rear tires decreases traction in most cases. 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). 87 Chevy C10 upper control arms. Characteristics of the metric 4-link, one of those four, are the same as discussed under the heading related to asphalt cars. Usually, the right-rear corner of the chassis moves more than the left-rear. LR bracket is 7 from axle tube to center of bottom hole, but still conforms to the 7.5 max length rules. 4. With the trailing arms toed in at the front you can use the J-Bar mounting angle to help steer the rear end through roll. Black & Red PCE 16A Coupler (400Volt, 3P+E Pin Configuration) 16A Lead Coupler with a current rating of 16, a voltage rating of 400 and a 3P+E pin "loose roll steer". Unbolt and remove one upper rear control arm using a " wrench. Let's expand on the other three systems. In the last pass of the night, the Chevelle delivered a 1.629-second 60-foot time on the way to a 7.014 / 99.71 mph pass. Trailing arm bushings come included (part No. This bracket is also built heavy, weighs 7.5lbs (with slugs) to help increase LR rear end weight. 4.0 drop trailing arm brackets slotted to accept offset slugs. Then this NEW trailing arm bracket kit is a must have. Rayburn of Rayburn Race Cars, a driver as well as a car builder, echoed much of what the other buiders had to say. Raise the Rear Panhard Bar Up on both sides. The RR lower most will run level. Metric Chassis Complete A-Arm Assembly $ 99.95; Camaro Chassis A-Arm Shaft Assembly $ 99.95; JOES 24" Pit Steering Wheel $ 199.95; Useful . July 1st. how the shortened bottom link pulls the bottom of the right side 4.0 from axle tube to center of hole. 4. 2- 175-B upper mounts. As a result, loose roll steer is reduced. The upper arms is where many very in opinion. Its on a car that Im helping with. Preload is another tuning tool to counteract body roll rotation. Instead of using some form of track locator or Watts linkage, the trailing arm triangluation keeps the rear end properly located in the car. Rear steer in a circle track race car is a condition caused by suspension movement. excessive if the rear of the chassis lifts a lot during acceleration. Masters added, "Any time we can press air against the sides of the car, we can help the car to turn." The front of the car felt the actual 400-pound rate while the rears "felt" like 200 pound springs. (Sold Individually). The setup is balanced when the LF and LR tire temps are similar. Wayne This is done to add more angle to the lower trailing arms, which adds roll steer to the rear, as the body rolls. A & A Manufacturing makes 95% of their product line in Michigan, including the stock trailing arm mounting kit. 3. Thats not necessarily bad. The company also sells ultra-lightweight rear spring cups (see Rear Spring Cups from A&A Holidays Wish List). To understand how a 4-link can be If both sides are configured to move in opposite directions, then rear steer can be extreme. The right-rear shock shows from 3 to 4 inches or more of travel, depending on the spring rates used. the other illustrations. Tack weld the slugs to secure them to the trailing arm. birdcage path. Following the anti-roll bar, you can use adjustable shock absorbers (front and rear), front suspension limiters, and to a lesser degree, specific coil spring rates to get the car to hook up. reducing loose roll steer. on rough race tracks. It takes less than two hours for an experienced welder to install the kit.. 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. sub frames in these cars move a lot when the car lifts at the front changing the pinion angle.. front sub frame is not tied Required fields are marked *. the race car upon corner entry -especially when both coil-over units are Wayne Owner-operator at Race Products Inc. If it had angle, as it moved up it would lengthen the wheelbase then pass level and start shortening the wheel base as it moves upward. about rear suspensions. 60 offset new reproduction stamping Ford 9 housing with new 3 tubes and GN hub type snouts. Thanks so much! tuning a 4-link, it is important to understand the relationship between Adjustable 73 - 77 . Not only does the condition of rear steer affect the entry and middle handling balance, it affects handling under acceleration due to the thrust angle of the rear end being either right or left of the centerline of the car. I am setting up a GM A body 1972 Monte Carlo. $15.75. Wehrs Modified Valance Support. clamp brackets (since there's no longer any indexing of the movements of the without compromising forward bite. 88 metric lower trailing arm $65.00. suspension by angling the trailing arms upward toward the front of the A downside to using the truck arms is not related to steering characteristics, but due to a narrow spring base when the springs are mounted directly on top of the truck arms, creating a narrow spring base in the rear. Trailing arms must also be running forward at the correct car builder design angle. (Steel). Simply replace the slug with different combination of offset slugs. 1- LZ-13-B lower mounts (pair ) 1- 384-B shock mount (right) 1- 384-C shock mount (left), *LZ-13-B is a laser cut mount that has been welded on the proper angle to fit a GM metric chassis. Heres a look at an adjustable upper trailing arm fitted to a GM G-body. Reply. What is wrong ? For example, in illustration 2A, both the top and the bottom links Can be used on both 9" Ford and quick change rear end tubes. Lower the Rear Panhard Bar on both sides (frame and rear-end attachment). 3 to 4 degrees nose-down is recommended. Notice, in illustration 2D, illustration 2B where the links are level. To ensure the pinion is in the correct location under power, it is typically set nose down in its at-rest (static) position. Those conditions rarely exist on dirt. These tapered profile spring cups are manufactured from high strength steel and are designed to minimize any stretch and bending while still being lightweight. (and tire) are forced towards the race track. Clamp Brackets are used to mount the This Spring Cup is extended to hold the spring while the chassis hikes for Northern Sport Mods and . 2022 Racelogic Street Stock Class Workbook, 1-7 Getting Your Cross Member Where You Want It, 1-14 Camaro Drag Link vs Metric Drag Link. Simply replace the slug with different combination of offset slugs. The condition is referred to as AA-175-B) are constructed from stout 5/8-thick steel. coil-over units directly to the axle housing. The rear axle Maybe a up is a starting point. I would like know what the ic would be on a g body with a 9 inch in the rear with stock suspension. This will make it easier to line up the new control arms when they are installed. Richards added that today, the Z-link or swing-arm suspension can have nearly as much rear steer as the 4-link, without the excessive loading of the left-rear tire. Many teams use varying amounts of rear steer to adjust to constantly changing track conditions, a product of variations in moisture content so common in dirt racing. Dave is the owner of Hammond Motorsports. Welcome to J-AUTO! Some manufacturers have added multiple mounting points on the front and rear chassis mounts. tire loadings. It may not display this or other websites correctly. Dartmouth, Nova Scotia. coil-over units on This produces a motion ratio that causes the spring to move less than the chassis per degree of roll and/or inch of squat. correct any corner entry handling problems caused by With this design, lateral movement of the rear end causes rear steer. You can see how this adjustment works in illustration 2B. you to better understand the 4-link suspension. right side link is from 3 to 5 higher than the left when the chassis . In the past, drivers would set up the car for exit off the corners, throwing the car sideways by breaking the rear tires loose. This promotes forward bite without causing the car to be tight on entry or in the middle of the turns. The four holes for adjusting the lower trailing arm angle are all symmetrical, so when you move the trailing arm up or down it does not change the wheelbase of the car, said Tom Nolff, of T&D Custom Fabrication in Grant, Michigan. These tapered profile spring cups are manufactured from high strength steel and are designed to minimize any stretch and bending while still being lightweight. In more recent years, teams have been setting up the car so that the left side raises up quite a bit. I also have a trz weld in style arb. Insert the bolts to the ends of the control arm Lower the jack from the transmission Tap the bolt into the control arm Raise the rear suspension to simulate ride height Torque the bolt to 95 foot-pounds Torque the bolt near the rear axle to 103 foot . Oct 12, 2013 #2. Picture does NOT represent all jig options. DCA RaceFab : Suspension Rear Trailing Arms - Chassis Exhaust Misc Linkage / Spacers Rear End Suspension Transmission Engine / Fuel Cooling Steering Brakes Shop Solutions racing, sportsman, hobby stock, street stock, chassis, control arm, bushing, spherical, spherical bushing, delrin . Emirates offers flights to Ho Chi Minh City (SGN) and 139 other destinations. The upper arms can be used to set the pinion angle by adjusting both arms in the same direction and by the same amount. The lower links are angled from a top view with the front pivots narrower than the rear pivots. of a 4 link suspension are the link lengths designed into the suspension Most of the Z-link systems utilize a spring mounting system that attaches the coilover spring to the front link. gained by running the trailing arms upward to the front of the race car. The Metric four-link suspension design is a bit different than most other rear suspensions. . birdcage moves forward during chassis roll instead of rearward as in A 4-link Mounts J-Bar to QC rear end 4 3/8 offset from pinion. with the very soft chassis meaning floppy front subframe is 4.5 enough? Mike Kojima says: July 15, 2019 at 4:38 pm . to be loose. As the rear corners of the car move, along with the controlling arms that locate the rear-end fore and aft, each side can move the wheel on that side forward or to the rear. KT-1B) makes removing a GM rear end from a GM Metric chassis much easier. Make small adjustments if you feel a need. You can use cardboard, Keith Masters of MasterSbilt Race Car Chassis said, "The reason chassis builders build 4-bar cars is because of rear steer. The system works well enough on the street, but not so well when it comes to hooking up at the drag strip, especially with big horsepower. Depending on the angles of the trailing arms or bars, each rear wheel can be made to move to the front or rear. 1 diameter x 11 long weight jack bolt. Get the rear end "Free" dont torque down the bolts on the bushings and bind everything up. Cars with 15-inch wheels should have a measurement of 205mm (8.07") in front. length and/or angle difference in the upper and lower links. This Spring Cup is extended to hold the spring while the chassis hikes for Northern Sport Mods and Limited Mods. These arms also use rod ends on each end to prevent binding when under load. Decrease the Angle of the Upper Trailing Arm. I have edelbrock adjustable uppers with non adjustable boxed lowers. Short links( from 3 to 4 shorter than the upper links) generally work It comes with a locking bolt to tighten the bushing. The bar essentially controls weight shift from side to side, preventing the body from rotating on the launch. In order to keep the driveshaft and U-joints operating in a (more or less) straight line when youre on the throttle, the pinion angle has to be correct. The Standard 4-Bar System Additional washer added on end to extended life of bushing in severe conditions. . suspension moves. One theory related to having the attitude of the car sideways involves the use of the aerodynamic aspects of the car. Raise the front LR trailing arm mount. One trick I always used was to drill through the nut and bolt on the arms and use a cotter pin to lock the nut. Mounting them higher will shorten the instant center point too much, causing violent launches for high horsepower cars. cause a gas pedal push. roll steer are overly affected and handling becomes inconsistent. Adjustable rear trailing arms are also available for specific applications. (Sold Individually). shortening the lower links, is a reduction in loose roll steer. His company has experimented with dirt track aero in the past. The instant center is also rather high; the angles of the bars can raise it somewhere above the front wheel spindle. The bushings wore out in the lowers and my left tire got in the wheel tub. So how do you make it work? The technology related to rear steer for asphalt and dirt are somewhat different. 2- 175-C bushing for upper mounts. Under most current rules, there is no adjustment for amounts of rear steer with these systems. Lower the front LR trailing arm mount. From personal experience, theyre great quality. So, teams need to take this rate difference into account. 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. Dirt Late Model cars can be designed with a considerable degree of adjustment for rear steer. Housings havefill and drain plug installed. this important function of the lower links. This year marks the Outside Groove Director of Photographys 51st year of covering auto racing. suspension is to shorten the bottom links. 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. We can relate 1/8-mile e.t. If excessive, loose roll steer can cause a loose Part No. These bars are used to center the wheels in the wheel well and to set the wheelbase from side to side. You are using an out of date browser. Adjust the pinion angle. As you can see, the bar ties the upper and lower trailing arm mounting points together, which spreads the load and helps to prevent mounts from tearing out. It comes with a locking bolt to tighten the bushing. suspension). Wayne Wehrs Body Braces. try to drive underneath the chassis as the rear axle pushes the race car Ask me how I knowL-O-L. Hope that gets you sorted out. We hope the information in this article, combined with your Kit contains: (2) Rear upper control . Add to cart Details. Dave here in Saskatoon been racing a g body for many years now and struggle to get However, indexing can cause the rear suspension to be too harsh Housings have fill and drain plug installed. Brand new Stamped steel, C-channel arms are strong and sturdy Improve the handling of your '78-'88 GM Metric rear suspension by replacing twisted or worn out rear control arms 11" center to center Sold each IMCA Approved. Decrease the Angle of the Upper Trailing Arm. to -mile numbers by multiplying by 1.54. Adaskaveg got his start working for track photographer Lloyd Burnham at Connecticuts Stafford Motor Speedway in 1970. A level panhard bar ( same mounting height on both sides) means force is vectored laterally to the tires. Be aware that trailing arms angled uphill too steeply can hold the mounted 5 downwards to the front, coupled with 17 1/2 top links, Mounting both If the front is diving under braking then add anti-dive to front suspension. But it also had downsides . Description. A good Tack weld these washers to the outer flange of your bushing to create a retainer for the rubber. Hotchkis and Global West make similar control arms for Mustangs and GM A- and G-bodies. ~ index. Here is how each system functions and how they can be adjusted for the "degree" of rear steer. Decrease Upper Control Arm Angle on the Rearend. I like to see a 1" long weld on the top inside of the right side. In simple terms, it keeps the body from roll rotating on the launch. Looking for that edge over everyone else. All we had to do now was work on consistency. AA-621-A fits 3 axle tubes $14.95. This will add Roll Steer as the chassis rolls over in the turn and the LR arm scribes an arc forward and shortens the left side wheel base. Increase Left Rear Spring Rate. Departing from Ho Chi Minh City. On most asphalt 3-link cars, the right-rear trailing arm mostly controls rear steer due to body roll. On the left side, the bottom For cars with spherical bearings (rod ends) or solid rear suspension bushings, most racers use a pinion angle between minus one to minus two degrees (minus is negative angle, or pointing down). The following examples and illustrations should help you to understand For example, you want the top link to be perpendicular to the rear end housing and parallel to the car. Indexing can improve driveability by keeping the race car flat in the I'm new at this how do u do that and does it makr a big difference. 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. You should keep in mind that any loading of the rear tires caused by You can also check to enhance the forward bite. have qa1 adjustable coil over shocks without the coil have a tube welded across the frame at the back to mount the shocks like a ladder bar where the chassis tends to push. When racing on dirt, watch the conditions and be prepared to make changes accordingly, not just to the setup, but also related to rear steer. Use this kit to build your own custom rear end. (USRA/IMCA Stock Car Legal). 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. mounted 15 upwards to the front. 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. stop and go or slick race tracks. If you have a Fox-body or SN95 Mustang, a 1980s GM G-body (Grand National, Malibu, El Camino, etc.) Location. Any of you guys changed any angles on trailing arms etc on a metric to make it faster? Kit includes required Custom length Double Adjustable upper control arms. For most track MAXIMUM Performance right side climbing panhard mount for Ford 9 rear ends. We can see the effect of the Sprint Car wing in the turns-as the cars actually roll left due to the pressure differential developed on the flat wing sides-as the cars go sideways at a high speed. This kit includes two Pull bushings, two steel spools, a rectangular mount tube and side gusset bracket. An anti-roll bar can also be mounted on the rear axle housing. Among Adaskavegs many awards are the 1992 Eastern Motorsport Press Association (EMPA) Ace Lane Photographer of the Year and the 2019 National Motorsports Press Association (NMPA) George Cunningham Writer of the Year. We've Where did I run mine? traveled by the centers of the birdcages during chassis roll. Balance the Front and Rear stiffness. Followed your advice and got a set of adjustable lowers. Notice how this This will give you a lower rear roll center and aide side bite. The car was set up and driven more like an asphalt car and it was fast. links have to be extremely short to minimize loose roll steer. The two most critical factors to the performance As the suspension in a car wraps up, the pinion is driven upward. but there are ways to get that back. clamp brackets to mount the left coil-over unit ahead of the axle . AA-384-B and AA-384-C), made from 3/16-thick steel, sit on the back of the lower trailing arm mounts. On extremely slick race tracks, you The Z-link System 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 . by comparing the different paths drawn on your model. [3] Advantages of Trailing Arm with Camber Links The lower trailing arms can be no lower that 2 3/4" from the "bottom" of the axle tube. I want just for street use, nothing but just Soft Ride. Insane video on the induced rear roll over steer. The live class took place January 22-23, 2022. what wold be the best angles to be at for most foward bite along with handling four all four links ? Part No. handling condition that negates the benefits of the forward bite gained The GM Metric adjustable rear trailing arms will aid in adjusting pinion angle, centering the rear end and adjusting wheel base. birdcages typically move down much less than right side everything is a compromise. correctly. right amount of loose roll steer can help a race car to turn the corner change of 5 can make a noticeable change to handling. This condition may Also pinion angle with stock bushings. But birdcages caused by the upper links. When If you want to insert bushings with a press rather than a mallet, opt for part No. Dirt Rear Steer (Try to bounce the rear of a car with a 4-link rear of the How to find roll centre in anti-dive or anti-squat double wishbone suspension, where upper and lower arms are at angle (side view)? A well designed 4-link provides good forward bite and the proper The 4-bar suspension is highly adjustable and can be made to steer both directions. The only reasons to adjust the upper bars on a triangulated four-link are to set the pinion angle and to center the rear axle side to side in the car. During chassis roll, indexing loads the right rear tire and unloads article to determine the correct link lengths for your application. shocks and springs. NOTE: If installing on a Frankland quick change, the bracket will need to be modified and reinforced to fit. . The bottom of the left side 2-12 Checking to Make Sure Your Rear End is Straight, 3-2 Distributor & Electronics Maintenance, 5-18 Counting Your Rounds & Brake Problems, 6-14 Wrapping Tires & Chemical Treatments, 8-13 How Driving Style Affects Shock Builds, 8-17 Starting Point for Off-the-Shelf Shocks. When one wheel moves more than the other, we have a certain amount of rear steer. 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. 6. Improve the cornering capabilities of your race car with these new rear control arms and bushings from Speedway Motors. When selecting springs for your 4-link, you should Whiteline Rear Trailing Arm Upper Bushing - Holden H Series/Monaro HQ, HJ, HX, HZ/Torana W51514 Finally, Im not exactly sure what you mean by a floppy front subframe. Thanks . and rearward (R.S.) This has been confirmed by studying data from onboard computer systems during testing that show shock travel amounts in the turns. position) instead of forward as in illustrations 2A and 2B. Spring Perchs & Brake Caliper Brackets are now Bolt-On Accessories (not included in Rear End Assembly Price). I am dropping my ride height 2. The bearing allows for smooth movement without the binding a rubber bushing can cause. Metric 4 Link Setup For Dirt steve smith autosports tech tips, the home of the jet mod and jet phantom the championship dirt track modified and stock chassis offering a full inventory of high performance racing parts racing safety equipment racing components and more lf 5 1 2 rf 5 3 4 lr 6 rr 6 1 4 our setup manual is the most in depth mod . When the track goes slick, especially dry slick, rear steer is needed. You should draw the paths to include Hes authored five how-to books and written over 4,500 tech articles that have appeared in sixty different high performance automotive, motorcycle and aviation magazines worldwide. A 200-pound spring in a Z-link car feels more like a 4-link car, where the coilover is mounted to a birdcage with a 100-pound spring installed. Wehrs Modified Valance Support Weld On Clevis. Compare the measurements to specifications. I am going to raise the car next to achieve ideal front lower control arm angle (still to low for that) then corner balance and tweak from there. can tighten overall corner handling by using The track in this case was banked and had a lot of grip. To see if rear steer is an important tuning tool, we turned to some experts. However, keep in mind that chassis roll causes the link angles to 9-5 Upper A-Arm Mounting Points Metric. PEM 9" Grand National Limited Floater Rear End Housing, RE-SSM-5800 is a 58" housing with a 0 pinion angle, stock mounts, and GM Metric caliper mounts. What effect would this have on roll center and other aspects of rear geometry for a road race application? The length of the upper links should be at least 17" . birdcages and mounted to An anti-roll (or anti-sway) bar is most often used to preload a triangulated four-link. Wayne thanks for the input They constantly introduce new products to their lineup. The upper arms on a triangulated four-link are used to center the rear axle housing from side to side; you shift the rear axle housing left or right, depending upon which bar you adjust. you will speed up your learning process by working with a model. Wehrs Bent Suspension Bar Angle Finder. Those cars have multiple holes, allowing the angles of the control links to be altered to produce more or less rear steer. 2-5 Rear Spring Table. My upper a arm is at a 10 degree angle pointing down towards the front. These trailing arms have fluted greasable, graphite/polyurethane bushings, which are superior to the stock rubber bushings. (See illustration 2A.). This is accomplished by causing the right-rear wheel to move back and the left-rear wheel to move forward as the car rolls. These notes are based on the Directorate General of Shipping Syllabus for the three month pre sea course for deck cadets BMS Racecars - Winning's not just a goal it's a tradition! My car had 7Deg of angle it. Long bottom links (equal in length or no more than 1 made to provide such handling, you must first understand a few basics Distance from link mounts to transmission output and 3'rd yoke will dictate mount position. Basically, we've position the bottom links to counteract the