metric chassis trailing arm angles

As the left side of the car travels up, the front of both of the trailing arms are angled upwards so that the left-rear tire tries to drive up under the chassis, loading the left-rear tire considerably. The front of the car felt the actual 400-pound rate while the rears "felt" like 200 pound springs. These tips are for an independent a-arm front suspension and 3-link rear suspension type of car, but may apply to other types of suspensions as well. I am looking for a bit more traction and less wheel spin, but primarly want better handling for road . birdcages during chassis roll. AA-621-C is an offset spring cup, which sits 2-1/2 off center of a 3 axle tube $14.95. AA-175-D. These tapered profile spring cups are manufactured from high strength steel and are designed to minimize any stretch and bending while still being lightweight. Dartmouth, Nova Scotia. Tubular arms are constructed of 1 1/4" diameter .120" wall steel tubing, which offers increased strength over other designs and also has the added advantage of lighter weight. (and tire) are forced towards the race track. the bottom of the Wehrs Modular Non-Adjustable T-Bar. . suspension. 2- 175-B upper mounts. A & A Manufacturing makes a similar trailing arm mounting kit for racers using Ford 9 rear ends in GM Metric chassis (part No. West Coast Metric - Suspension Parts, Front & Rear. Bushings in Upper Mounts Designed for stock cars with a 7.5 max trailing arm length. sensitive to adjustments. The two most critical factors to the performance The reason rear steer aero might be important comes on dry, slick surfaces, where the tires do not grip well. Lower the front LR trailing arm mount. Heres a better look at a trailing arm mounting brace. A rear end that is steered to the right of centerline causes the thrust angle to be pointed to the right of centerline and makes the car loose on entry and loose on exit under acceleration. 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. Typically, indexing causes the coil-over mounts, if located on the If not, no amount of adjustment will get the thing down the track properly. 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. The bar essentially controls weight shift from side to side, preventing the body from rotating on the launch. At the nose, Id do the same (spherical bearings or Delrin bushings). I am setting up a GM A body 1972 Monte Carlo. correct any corner entry handling problems caused by If you want to insert bushings with a press rather than a mallet, opt for part No. All driving train actually repalced with Moog components.. Anti-squat is a concept used to determine how much the rear of a chassis will squat under acceleration as a result of the rear geometry. Has boxed lowers, adjustable uppers , stock springs and shock. Remove only one control arm at a time. This has been confirmed by studying data from onboard computer systems during testing that show shock travel amounts in the turns. Dave's Tip - "You should always tack weld them in place. birdcage moves forward during chassis roll instead of rearward as in or something like an early Chevelle or a GTO, it has a triangulated four-link rear suspension.This type of suspension has coil springs and upper and lower trailing arms (also called control arms).The upper arms are angled to form the triangle that gives the suspension its name. We stated earlier that trailing arms mounted upwards to the front of The GM Metric adjustable rear trailing arms will aid in adjusting pinion angle, centering the rear end and adjusting wheel base. to be loose. I was looking for more info on stock rear 4 link trailing arm angles. 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. I'm new at this how do u do that and does it makr a big difference. is at ride height. We can reduce loose roll steer by lowering the bottom links at the clamp brackets are used in front of the axle, axle wrap-up during Decrease the Pre-Load on the Stabilizer Bar. The roll of the chassis and the movement of the Panhard bar are the two components that influence the amount of steer in these systems. Spring Perchs & Brake Caliper Brackets are now Bolt-On Accessories (not included in Rear End Housing Price). Dirt Rear Steer here a simple Q as hope life for you: owning an base malibu sedan 81 and had changed coils (some, new and used), and new gabriel stock shocks, Im banging my head on the paviment as this car has absolute no suspension. shocks and springs. I hear of 305 cid stockers running in the high 1.40s far less hp I have adjustable qa1 shocks For most track The technology related to rear steer for asphalt and dirt are somewhat different. Raise the Rear Panhard Bar Up on both sides. 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. Rayburn of Rayburn Race Cars, a driver as well as a car builder, echoed much of what the other buiders had to say. Dual internal gusseting provides strongest rear end in the industry. We never need our suspension to steer the rear end to the right of centerline on asphalt. Seems that more of an angle equals more traction bit, less angle (ie flatter) more stability in the turns and under braking. Tuning With Rear Steer taken off The popularity of the 4-link suspension is due primarily to its 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). 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. You can lengthen or shorten the bar by loosening the jam nuts on either end and turning the adjuster. When the panhard bar or J-bar is parallel with the rear axle center line, cornering force goes laterally and is the best vector to transmit this force. Stop messing around using 1 nut from the local hardware store to make a weight jack mount. To help understand the Instant Center you can visualize a triangle (Fig. It takes less than two hours for an experienced welder to install the kit.. US $239.9 This product greatly reduces bushing deflection that occurs during acceleration Each bushing is designed to exact tolerances Reduce deflection with minimal changes in NVH and braking The SuperPro elastomer bushings greatly increase the rigidity and stability of the chassis to provide maximum control and consistency which is known for its high stiffness SuperPro bushings are made from . On extremely slick race tracks, you 2. The Standard 4-Bar System Specifically designed to increase LR drive off the corner and corner entry adjustability with multiple hole adjustments on the RR. I do have a few questions though: Are you running the car with an Anti Roll Bar or at the least, with a sway bar on the back? Has gone 1.29 60 ft on spray, has 28 10.5 et street tires on it also. acceleration causes the rear axle & chassis to separate. In racing, we have the maximum amount of traction from a pair of equally loaded tires on the same axle. Assembly includes: 2.5 MAXIMUM GN hubs, hub bearings, seals, brake rotor, drive flange, axles and all hardware necessary. Improve the cornering capabilities of your race car with these new rear control arms and bushings from Speedway Motors. Trailing Arm Brackets If you look at a modern dirt Late Model, the sides are made up of big, flat panels similar to the sides of a Sprint Car wing. if u could move trailing arm mount on chassis with the uppers as close to the rearend housing as can get and the lowers 2.5 away from housing. 1-15 How Important is it to Bump the Left Front? Some forward bite may be lost when Third and fourth generation Camaros and Firebirds with torque arm suspensions also have a long instant center and are known to hook up on pretty much anything. 2- 175-C bushing for upper mounts. on rough race tracks. Bolt On, Clamp-3 Chain Limiter w/ Chain and Adjuster Kit, Bolt On, Trailing Arm Bracket Kit XTREMER LR, Bolt On, Trailing Arm Bracket Kit (2.5 SINGLE HOLE), Bolt On, Trailing Arm Bracket Kit (2.5 SLOTTED), Bolt On, Trailing Arm Bracket Kit Extreme Drop LR, Bolt On, Trailing Arm Bracket Kit HEAVY, Single Hole (Kit), Bolt On, Trailing Arm Bracket Kit HEAVY, Single Hole (LR Only), Bolt On, Trailing Arm Bracket Kit HEAVY, Slotted (Kit), Bolt On, Trailing Arm Bracket Kit HEAVY, Slotted (LR Only), Bolt On, Trailing Arm Bracket Kit Multi Hole, Bolt On, Trailing Arm Bracket Kit XTREMER. Used on millions of cars - BMW, Mercedes, Ford and even Rolls Royce - semi-trailing arm rear suspension had some huge advantages. A link length change of 1" or a link angle The live class took place January 22-23, 2022. 3. 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. It comes with a locking bolt to tighten the bushing. 6. forward (See illustration 1). Under the wrong conditions, it can ruin your handling. We usually need to position the angle of the trailing arm so that the front mount is higher than the rear mount by roughly one third of the distance that the front mount will move down during cornering. Housings havefill and drain plug installed. of the The problem with some trailing arms made for Mustangs and GMs A- and G-bodies is they tend to create a very short (further from the engine) instant center by changing the angle of the bars. * puts the roll center 3.3 inches off the ground. Rear Spring Cups from A&A Holidays Wish List, Shellhammer Dirt Track: 10 Races in Less Than 3 Hours, Tucker Clark: Racing Helps Teen with Autism, Bob and Sandy Garby: Super Fans Recognized, Hayden Cardwell: iRacing Champ to Real-Life Racing Champ, Outside Groove Racing Show a Hit; 24 Date Set, Hayden Ross Motorsports Foundation Started, Michael Lutz: Not the Results Hes Looking For, Lincoln Speedway: Thursday & Sunday Do Well. during acceleration (due to the axle thrust effect). Picture does NOT represent all jig options. Wayne Scraba is a diehard car guy and regular contributor to OnAllCylinders. Now available value added Metric Rear Control Arm . short bottom link arrangement of illustration 2D on the right side. the indexing and the link angle changes during roll or bump. Wehrs Body Braces. If you run the frame side of the J-bar is higher . everything is a compromise. The setup is balanced when the LF and LR tire temps are similar. links have to be extremely short to minimize loose roll steer. Consequently, it may be necessary to increase rear spring rate Here is how each system functions and how they can be adjusted for the "degree" of rear steer. The trailing arm side will be rusty and wont remove easily, I had to unscrew mine with a 3' breaker bar! preceding paragraphs should help you understand why. Housings have fill and drain plug installed. the race car enhance forward bite by using axle thrust to quicken the Metric Chassis Complete A-Arm Assembly $ 99.95; Camaro Chassis A-Arm Shaft Assembly $ 99.95; JOES 24" Pit Steering . BMS Racecars - Winning's not just a goal it's a tradition! by running the trailing arms upward towards the front. Mike Kojima says: July 15, 2019 at 4:38 pm . Unbolt and remove one upper rear control arm using a " wrench. 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. If you have a Fox-body or SN95 Mustang, a 1980s GM G-body (Grand National, Malibu, El Camino, etc.) On a Late Model, this air pressure difference may help keep the car on the track by virtue of having the car go through the air at an angle, causing both a high pressure on the leading (right) side and a lower pressure on the trailing (left) side. Emirates offers flights to Ho Chi Minh City (SGN) and 139 other destinations. The key to correctly AC A/C Compressor for Honda Civic L4 1.6L 1.5L 1994-2000 & CR-V 2.0L 97-01. $15.75. REAR SUSPENSION: The following is a general list of rear ends and their dimensions to help narrow the search for a possible candidate to replace the torque tube rear end or just get a better set of gears for highway driving. During chassis roll, indexing loads the right rear tire and unloads Large 1 NPT fill plug installed for easy filling or connecting to fill tank. Thats not necessarily bad. He will be showing the latest tools to enhance your chassis set up. 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. This is your problem, (sprung v. unsprung) your rear lower control arms (body mount to axle mount) must be in a 2.0-3.0 degrees (max) downward slope to the rear axle. My car had 7Deg of angle it. 4-link, or use the design parameters mentioned in this article, to help at least 3" of rebound movement for the left Spring Perchs & Brake Caliper Brackets are now Bolt-On Accessories (not included in Rear End Assembly Price). In dirt racing, it may be advantageous to incorporate a large amount of rear steer under certain conditions. Asphalt stock cars have four predominant rear suspension systems and all of them produce some amount of rear steer. Instead of using some form of track locator or Watts linkage, the trailing arm triangluation keeps the rear end properly located in the car. There are four types of rear suspensions used in most dirt cars that are significant to study regarding rear steer. 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. Also, how old are the shocks and have you ever had the valving checked? 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. extremely short links change their angles radically whenever the Welcome Guest. There are three items to address: shocks, anti-roll bar, and adjustable trailing arms. The condition is referred to as 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. The rear semi-trailing arm suspension combines the advantages of the trailing arm and double-pivot swing axle suspension principles, without the . A racer himself, he was the winner of the Street Stock Nationals in 2019. reducing loose roll steer. LR bracket is 7 from axle tube to center of bottom hole, but still conforms to the 7.5 max length rules. You should draw the paths to include 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). Can I convert a combustion engine car to a hybrid car? This produces a motion ratio that causes the spring to move less than the chassis per degree of roll and/or inch of squat. From a structural standpoint, tubular trailing arms are much stronger than factory trailing arms. it feels as a plank over nude bearings on the road .. KT-1B) makes removing a GM rear end from a GM Metric chassis much easier. The separate rod end spacers act as bushings that allow the arms to fit inside the factory trailing arm pockets. clamp brackets and ahead of the axle can improve forward bite on Adjust the length of the control arms as needed to achieve the desired pinion angle. Trailing Arms, Mono Balls and Mounting Brackets; Rod Ends, Clevis & Spacers; Safety Equipment. Decrease the Angle of the Upper Trailing Arm. A & A Manufacturing makes a similar trailing arm mounting kit for racers using Ford 9 rear ends in GM Metric chassis (part No. I had 17 Deg of angle in my car, down in front and up in back. Copyright Racelogic Chassis School 2023. Long bottom links (equal in length or no more than 1 Outside Groove Note of Transparency: A&A Manufacturing paid for the production of this article. Location. Most often, the factory trailing arms are simply a stamped metal arm. The side bite trade off is a big one. 1 diameter x 11 long weight jack bolt. Jul 23, 2001. When selecting springs for your 4-link, you should JavaScript is disabled. Pinion angle is measured between the pinion gear flange and the driveshaft. 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. birdcage forward during chassis roll more than the longer links in REAR - On each side of the vehicle, measure the distance (2) from the center of the outboard trailing arm-to-body mounting bolt (1) to the floor or alignment rack/lift runway surface. CTS Upper Metric Trailing Arm Mounts for Ford 9 inch housings. (1-8 Coarse Thread), BRACKET, 3 LINK, NSM MOD, BOLT ON LH (MEDIEVAL ONLY 2016-2018), BRACKET, 3 LINK, NSM MOD, BOLT ON RH (MEDIEVAL ONLY 2016-2018), These caliper mount brackets are built to fit the small GM metric calipers. designing and tuning a 4 link is to understand the significance of these It comes with a locking bolt to tighten the bushing. AA-175-D. If the link angles become more upward on the left than on the For more than 50 years, A & A Manufacturing has worked closely with racers and chassis fabricators. 9-5 Upper A-Arm Mounting Points Metric. I also have a trz weld in style arb. Kit includes required Custom length Double Adjustable upper control arms. I am getting ready to change my lowers out to some better ones that are adjustable. Clamp brackets are sometimes used on short, slick tracks to improve This configuration is common in General Motors cars built in and around . or something like an early Chevelle or a GTO, it has a triangulated four-link rear suspension. Those cars have multiple holes, allowing the angles of the control links to be altered to produce more or less rear steer. you will speed up your learning process by working with a model. When the rear links are too short forward bite and Use this kit to build your own custom rear end. Another method used to reduce the loose roll steer of a 4-link So how do you make it work? document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); This site uses Akismet to reduce spam. The lower links are angled from a top view with the front pivots narrower than the rear pivots. The front locating points must be in the stock locations. In a high horsepower car, engine torque tends to rotate the car so the right rear tire has more bite. To really add over steer at the rear end housing you can mount the front pivot point of the RR trailing arm towards the center of the car. try to drive underneath the chassis as the rear axle pushes the race car . just ordered the adjustable lowers In short With so much movement, we can plan out our rear steer just about any way we need it. It may not display this or other websites correctly. shortening the lower links, is a reduction in loose roll steer. 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. You can play with all of these a little to work on plunge/roll steer. Learn how your comment data is processed. without compromising forward bite. If the Panhard bar is mounted on the right side of the chassis and level to the ground, the rear end will be pulled to the right, and will steer to the left when the chassis moves during cornering. 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. (Steel). SportMod jigged. 2.50 from axle tube to center of hole. "Rear steer helps the driver get the rear end around on dry, slick tracks without having to break the rear tires loose," said Garrison. the race car upon corner entry -especially when both coil-over units are What effect would this have on roll center and other aspects of rear geometry for a road race application? For example, in illustration 2A, both the top and the bottom links the right side Part No. This one is made by Hotchkis for GM A-body cars. birdcages, to rotate against the shocks and springs during Ground clearance at bump and uptravel at ride height will dictate link angle. Check Tire temps, if LF is coolest (unbalanced setup): Decrease front springs, maybe even use reverse split (LF stiffer). Street Stock. gained by running the trailing arms upward to the front of the race car. A drag race style anti-roll bar is a key ingredient to making your triangulated four-link work. Under the right conditions, rear steer can be beneficial and enhance performance. C.J. AA-621-A fits 3 axle tubes $14.95. The asphalt racing surface provides a lot of traction, even on those flat "slick" tracks. and parallel to each other). 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. Adjust Cross Weight as changes are made to keep the car neutral. Compare the measurements to specifications. In turn, that bite tends to move the car toward the left. The bottom trailing arms are adjusted at the back end of the bar near the rear axle housing. However, a proven 4-link arrangement includes 15 1/2 bottom links, Keep in mind that any change to the birdcage rotates or "indexes" on the axle tube whenever the The instant center is also rather high; the angles of the bars can raise it somewhere above the front wheel spindle. Basically, we've position the bottom links to counteract the Loose roll steer causes the rear axle to steer towards the outside of A level panhard bar ( same mounting height on both sides) means force is vectored laterally to the tires. 3. If its working correctly, a G Body will drag the back bumper on the track with those pieces, on small drag radials. Knowing these basics, we need to look at each type of racing to see how rear steer affects each type of car and how we might improve our performance using rear steer. 4AN To for 8mm X 1.0 Metric Straight Adapter Vibrant. Your DS length will dictate your lower link length. it feels as a plank over nude bearings on the road .. Click here to remove banner ads from this forum. efforts, will provide you with an advantage. The left-rear suspension is designed so that when that corner raises up, the arms are angled, pulling the left-rear wheel forward towards the driver. clamp brackets. My rear end is a nine inch ford with the large pinion. An anti-roll bar can also be mounted on the rear axle housing. Required fields are marked *. If the front is diving under braking then add anti-dive to front suspension. Under most current rules, there is no adjustment for amounts of rear steer with these systems. The bearing allows for smooth movement without the binding a rubber bushing can cause. The rule about never steering the rear end to the right on an asphalt car does not apply on a dirt car. Decrease the Angle of the Upper Trailing Arm. Browse Suspension Parts, . The significance of this, for the purpose of this article, is that the chassis travel in a Z-link is enhanced compared to the 4-link suspension when using the same installed spring rate, and this causes quite a bit of chassis travel and related rear steer. Please Login or Register. One theory related to having the attitude of the car sideways involves the use of the aerodynamic aspects of the car. The company offers a wide array of quality chassis components at reasonable prices. change of 5 can make a noticeable change to handling. RAceman. Bars like this are typically welded into the chassis and tied to the housing by adjustable links. If both sides are configured to move in opposite directions, then rear steer can be extreme. You should keep in mind that any loading of the rear tires caused by This will make it easier to line up the new control arms when they are installed. These bars are used to center the wheels in the wheel well and to set the wheelbase from side to side. AA-175-B) are constructed from stout 5/8-thick steel. AA-621-D is a clamp-on spring cup, fitting 3 tubing $24.95. This induces less rear steer when the car squats on exit. Richards added that "if the driver has to countersteer the car a lot, you need more rear steer.". Simply replace the slug with different combination of offset slugs. This induces rear steer when the car squats on exit. Hes owned his own speed shop, built race cars, street rods, and custom motorcycles, and restored muscle cars. Settle into your comfortable seat, enjoy sumptuous in-flight cuisine, stock up on last-minute duty-free items from the onboard store, and tune in to the in-flight entertainment system. (more on this later). These arms also use rod ends on each end to prevent binding when under load. I like to see a 1" long weld on the top inside of the right side. 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. clamp brackets (since there's no longer any indexing of the A good KT-1A). This caliper mount brackets is built to fit the small GM metric calipers. Thanks . the race track. The length of the upper links should be at least 17" . Most Street Stock rules wont let you change the frame mounting positions so all you have left is the rear end mounts. mounted 15 upwards to the front. However, keep in mind that chassis roll causes the link angles to