Asphalt stock cars have four predominant rear suspension systems and all of them produce some amount of rear steer. Keep in mind that any change to the
There are a few similarities, but many differences in how we evaluate and use rear steer for each group. Under the wrong conditions, it can ruin your handling. The Impala spindles are the " hot set up " on a metric chassis. everything is a compromise. Make small adjustments if you feel a need. 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. For example, you want the top link to be perpendicular to the rear end housing and parallel to the car. The front may be too stiff compared to the rear. keep in mind the effect that indexing has on suspension stiffness. The condition is referred to as
Dave here in Saskatoon been racing a g body for many years now and struggle to get Basically, we've position the bottom links to counteract the
reducing loose roll steer. excessive if the rear of the chassis lifts a lot during acceleration. clamp brackets during acceleration will be accompanied by an
right and 10 to 15 on the left provide good forward bite. This is caused by the rear end swinging around the instant center, created from projecting lines through the arms to the front until the lines meet. After subframe support arm is out of the way, unscrew the . A lot of guys take that to extremes.". shocks and springs. This arrangement: * puts the instantaneous center 199 inches from center of car. stop and go or slick race tracks. With this system, the rear end stays located by virtue of the opposing angles of the upper and lower links. This trailing arm bracket use common offset slugs (sold separately) to allow you to change the amount of lead or trail in the rear end. Designed for stock cars with a 7.5 max trailing arm length. right amount of loose roll steer can help a race car to turn the corner
Wehrs Modified Valance Support Weld On Clevis. Semi-trailing arm suspension, handling and stability performance, non-linear vehicle model, Bees algorithm Date received: 17 November 2011; accepted: 3 February 2012 Introduction If you run the frame side of the J-bar is higher . article to determine the correct link lengths for your application. However, keep in mind that chassis roll causes the link angles to
$15.75. (Sold Individually). The 2-day class is broken down section by section. The Z-link System unloading of the rear tires during deceleration This unloading can upset
Great info! See the text for more information. path traveled by any trailing arm will affect roll steer. Wehrs Bent Suspension Tubes 5/8"-18 Thread. Big Chevy Impala and Caprice 1980 to 1994 casting number is 369056 for right side and 396055 for left side and if you can not locate these I can send you info on other substitutes. the bottom links are lowered but the effect on forward bite is usually
movements of the
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. this important function of the lower links. mounted 15 upwards to the front. Some will say run them as low to the rearend housing as you can. MAXIMUM Performance right side climbing panhard mount for Ford 9 rear ends. clamp brackets (since there's no longer any indexing of the
are used to help control loose steer. Show more About this course $299.00; 160 lessons . This bracket is also built heavy, weighs 7.5lbs (with slugs) to help increase LR rear end weight. Decrease the Angle of the Upper Trailing Arm. You may be required to make chassis adjustments to
Hes owned his own speed shop, built race cars, street rods, and custom motorcycles, and restored muscle cars. This saves wear and tear on your U-joints while . But as youll see in the photos, adjustable trailing arms are the firstand bestmethod of setting up a triangulated four-link for drag racing. On most asphalt 3-link cars, the right-rear trailing arm mostly controls rear steer due to body roll. These arms also use rod ends on each end to prevent binding when under load. and the right coil-over unit behind the axle. 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. Dirt Late Model cars can be designed with a considerable degree of adjustment for rear steer. roll steer are overly affected and handling becomes inconsistent. 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). Now with Ten properly positioned holes . His company has experimented with dirt track aero in the past. Kit contains: (2) Rear upper control . $64.00. 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. 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. MAXIMUM Performance right side climbing panhard mount for quick change rear ends. Mounts J-Bar to QC rear end 4 3/8 offset from pinion. What is wrong ? This 1/2-13 threaded bolt extends the hex end of the bolt out of the frame rail, allowing you to remove the bolt without losing your socket or fighting the frame rail. Depending on the angles of the trailing arms or bars, each rear wheel can be made to move to the front or rear. suspension). preceding paragraphs should help you understand why. traction characteristics desired by the chassis tuner. 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. Ground clearance at bump and uptravel at ride height will dictate link angle. 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. The difference is that now we can maintain rear traction-having never broken loose-and the car is angled somewhat sideways, and pointed in the right direction to get off the corner. These notes are based on the Directorate General of Shipping Syllabus for the three month pre sea course for deck cadets loose roll steer tendency caused by the steep angles of the upper links. 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. How to Determine Over-Amperage on Pulley Size Change. Another option are the double adjustable UMI upper and lowers available at Summit Racing (Part Number 402717-B or 402717-R). just ordered the adjustable lowers Indexing is greatest when there is a lot of
Suspension movement usually increases when the coil-over units are
Tack weld the slugs to secure them to the trailing arm. Condition: New. These new Currie 31-spline axles feature press in studs in a 54 3/4 wheel bolt pattern, , thick heavy duty bearing retainer plates, and tapered wheel bearings pressed on. links have to be extremely short to minimize loose roll steer. 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. 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. (Steel). 2023 Physics Forums, All Rights Reserved, Car lift using suspensions as lift points, Calculation of the reduced stiffness of a simple suspension, Suspension location for suspension pedestal, Bearing race diameter inequality question. Avoid these types of trailing arms for drag racing. I am setting up a GM A body 1972 Monte Carlo. forward on the left side during chassis roll. 266. The popularity of the 4-link suspension is due primarily to its
Then this NEW trailing arm bracket kit is a must have. That can work for a mild street or bracket car, but will make a high-horsepower car react violently at launch. You should draw the paths to include
Everything needs to be free to move or you will chase crazy problems and never figure it out. is at ride height. We can reduce loose roll steer by lowering the bottom links at the
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. We can relate 1/8-mile e.t. The length of the upper links should be at least 17" . The instant center is also rather high; the angles of the bars can raise it somewhere above the front wheel spindle. 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. birdcage to move forward more during chassis roll than in
I'm not sure of the Task Force width . Adjustable 73 - 77 . Wehrs Modified Valance Support. $149.99; 149 - Reward points. I am dropping my ride height 2. here a simple Q as 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. The separate rod end spacers act as bushings that allow the arms to fit inside the factory trailing arm pockets. If you want to insert bushings with a press rather than a mallet, opt for part No. Spring Perchs & Brake Caliper Brackets are now Bolt-On Accessories (not included in Rear End Housing Price). 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. $15.75. The company also sells ultra-lightweight rear . Now available value added Metric Rear Control Arm . I have tried different set ups with some success am now at 4.5 down corners. Their offerings include rod ends, spacers, bushings, clamps, brackets, and mounting hardware for a number of items, from shocks, to brakes, to fuel cells. 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 . AA-621-C is an offset spring cup, which sits 2-1/2 off center of a 3 axle tube $14.95. Stronger is Better. I use the H&R parts stuff anti roll bar Metric Chassis Complete A-Arm Assembly $ 99.95; Camaro Chassis A-Arm Shaft Assembly $ 99.95; JOES 24" Pit Steering . Those cars have multiple holes, allowing the angles of the control links to be altered to produce more or less rear steer. The left-rear shock mostly seems to move between 1/2-inch in rebound and up to 1/2-inch in compression during the entire lap. taken off
The car was set up and driven more like an asphalt car and it was fast. Trailing Arm Brackets Wehrs Bent Suspension Bar Angle Finder. The company manufactures the kits lower trailing arm mounts (part No. 4. 2-4 Offset Bushings and Trailing Arms. steer may increase whenever both bottom links are shortened! 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. Compare the measurements to specifications. Decrease the Split on the Rear Panhard Bar Heights. lowered the bottom links to a level position and now the bottom of the
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. handling condition that negates the benefits of the forward bite gained
In Stock . 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. A 1/2 inch height change from level can make significant handling changes. Which ones do you recommend? tuning a 4-link, it is important to understand the relationship between
Consequently, it may be necessary to increase rear spring rate
Let's expand on the other three systems. I will post as I no longer race, the biggest thing is the angle of the upper and lower control arms in the rear, you need to understand roll center and instant center to be able to adjust it correctly. This is correct. If excessive, loose roll steer can cause a loose
and rearward (R.S.) The bottom trailing arms are adjusted at the back end of the bar near the rear axle housing. Adjustable arms allow easy rear suspension . Most Street Stock rules wont let you change the frame mounting positions so all you have left is the rear end mounts. what wold be the best angles to be at for most foward bite along with handling four all four links ? Most often, the factory trailing arms are simply a stamped metal arm. When you find the correct amount of rear steer, stay there and tune the handling with the other components. The bushed end has a Teflon-lined QA1 stainless steel spherical bearing (rod end) with a stainless steel spacer. roll steer. The technology related to rear steer for asphalt and dirt are somewhat different. Add a good weld-on ARB out back. Made out of 1/2 thick steel to gain extra LR weight. There can be a handling trade-off, however, to the forward traction
suspension moves. Where did I run mine? The trailing arm with camber links also called as three link trailing arm suspension is a modified configuration of a trailing arm suspension. traveled by the centers of the birdcages during chassis roll. You can use cardboard,
tire loadings. birdcages typically move down much less than right side
KT-1B) makes removing a GM rear end from a GM Metric chassis much easier. Spring Motion Ratio Decrease the Pre-Load on the Stabilizer Bar. 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 . This condition will cause loose handling-especially
document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); This site uses Akismet to reduce spam. This Spring Cup is extended to hold the spring while the chassis hikes for Northern Sport Mods and Limited Mods. It seems not being an Irak/bu . The two most critical factors to the performance
At best, any trailing arm arrangement is a compromise between
They constantly introduce new products to their lineup. Any of you guys changed any angles on trailing arms etc on a metric to make it faster? 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 . The length of the bottom links are dependent on the roll steer and
I am settling 1100 hp LS Irwin turbocharged in it. 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. 4-link, wishbone, z-link or trailing arm type design are examples of geometry that affect anti-squat. where the chassis tends to push. BMS Racecars - Winning's not just a goal it's a tradition! birdcages (and the rear tires) rearward on the right side and
Reply. Buy Traxxas 9530: Suspension Arm, Front (Right), Black From RCMA For The Best Deals In Australia, We Also Have Same Day Shipping On All Orders Placed Before 3PM Today! They are angled to fit GM Metric chassis and have four holes for racers to adjust their trailing arm position. Leaf-Spring Systems - The leaf-spring rear suspension system locates the rear-end fore and aft, as well as laterally using the leafs. 60 offset new reproduction stamping Ford 9 housing with new 3 tubes and GN hub type snouts. Jigged with our: The lower trailing arms can be no lower that 2 3/4" from the "bottom" of the axle tube. Spring Perchs & Brake Caliper Brackets are now Bolt-On Accessories (not included in Rear End Assembly Price). The bars can be mounted on one side of the car so that only that wheel moves to create the rear steer. Cars with 15-inch wheels should have a measurement of 205mm (8.07") in front. change. The lower links are angled from a top view with the front pivots narrower than the rear pivots. chassis up during acceleration which can reduce the effectiveness of the
There is also steer to the left using this system, and because of the width of the front mounts of the lower-controlling links, rear steer can be considerable. Any angle up hill to the right rear will cause upward force on both tires and unload both tires. And have fun at SIR! The key to correctly
On the left side, the bottom
This produces a motion ratio that causes the spring to move less than the chassis per degree of roll and/or inch of squat. Characteristics of the metric 4-link, one of those four, are the same as discussed under the heading related to asphalt cars. ~ index. Be aware that trailing arms angled uphill too steeply can hold the
Wayne thanks for the input If the link angles become more upward on the left than on the
$ 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. "Rear steer definitely helps get into the corners on dry, slick tracks," Goddard said, "but you can put too much rear steer into the rear suspension. I was looking for more info on stock rear 4 link trailing arm angles. 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 trailing arms will improve handling of the rear suspension by replacing either twisted or worn out OE control arms. This Spring Cup is extended to hold the spring while the chassis hikes for Northern Sport Mods and . To understand how a 4-link can be
suspension. These systems only steer to the left and have a limited amount of steer. Adjustable lower bars are used to center the tires front to back in the wheel well and to make small wheelbase changes. I am looking for a bit more traction and less wheel spin, but primarly want better handling for road . Followed your advice and got a set of adjustable lowers. 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. 2-3 Starting Points for Bar Angles. However, indexing can cause the rear suspension to be too harsh
Heres a look at an adjustable upper trailing arm fitted to a GM G-body. On the left, we have reduced the forward movement of
of a 4 link suspension are the link lengths designed into the suspension
Seems that more of an angle equals more traction bit, less angle (ie flatter) more stability in the turns and under braking. [3] Advantages of Trailing Arm with Camber Links Indexing can improve driveability by keeping the race car flat in the
right, the left rear tire can become loaded more quickly than the right
Use this kit to build your own custom rear end. the right side
The Setup with Shane Tesch Topic - Center Pull #shorttrackracing #metalfabricator #latemodelstockcar #metalfabrication #chassisfab #stockcar #metalfab #motorsports #portcityracecars #superlatemodel #chassis #racecar #asphaltracing #pavementracing #racingparts In more recent years, teams have been setting up the car so that the left side raises up quite a bit. 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. These conditions call for a driving line that is more straight ahead. There are reports from the past of a team winning a race using four 400-pound springs on a Z-link type of car. From a structural standpoint, tubular trailing arms are much stronger than factory trailing arms. 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 . 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). Decrease the Angle of the Upper Trailing Arm. As a result, the loading of the rear tires
4. 4AN To for 8mm X 1.0 Metric Straight Adapter Vibrant. New info from @Fabman on RLCA angle: 3 to 5 degrees downward slope . Finally, Im not exactly sure what you mean by a floppy front subframe. This kit is affordable for most street stock racers, and it is both easy-to-install and easy-to-use, Nolff said. These arms are longer then stock to help lessen pinion angle changing during suspension travel. The rear axle
But
Posts: 5 Metric Rear suspension tricks Dec 31, 2012 20:24:48 GMT -6 . 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). (and tire) are forced towards the race track. Since we cannot lump them together, we will analyze them separately. Tuning With Rear Steer In turn, that bite tends to move the car toward the left. extremely short links change their angles radically whenever the
all the best parts. 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. Location. The upper arms are angled to form the triangle that gives the suspension its name. The live class took place January 22-23, 2022. suspension by angling the trailing arms upward toward the front of the
Then this trailing arm bracket kit is a must have. Joe Garrison of GRT Race Cars and Mark Richards of Rocket Chassis both said having rear steer capability in a dirt car was critical. Whiteline Rear Trailing Arm Upper Bushing - Holden H Series/Monaro HQ, HJ, HX, HZ/Torana W51514 best for tight, flat race tracks or on any track where the chassis tends
For a better experience, please enable JavaScript in your browser before proceeding. Under the right conditions, rear steer can be beneficial and enhance performance. Large 1 NPT fill plug installed for easy filling or connecting to fill tank. bottom link arrangement of illustration 2C on the left side and the
Please Login or Register. It uses four links, as the name implies, that are not parallel to the centerline of the car. 2.50 from axle tube to center of hole. I like to see a 1" long weld on the top inside of the right side. Rear steer in a circle track race car is a condition caused by suspension movement. Order your Trailing Arm 2 Piece Set - today at 1AAuto.com. Richards added that "if the driver has to countersteer the car a lot, you need more rear steer.". We can reduce
Fox80. attention to how the lower link adjustments change the paths traveled by
We hope the information in this article, combined with your
That thought echoed Garrison's point of keeping the rear tires connected to the ground going in and through the middle, helping to provide traction off the corners. Welcome to J-AUTO! the left rear tire to move forward. This is accomplished by causing the right-rear wheel to move back and the left-rear wheel to move forward as the car rolls. 2.5 drop trailing arm brackets slotted to accept offset slugs. Rear steer amounts-due to the Panhard bar angle-are regulated by the angle. KT-1A ). In a car with a non-triangulated four link, you can shorten the upper right trailing arm to increase the preload on the right rear tire. starting point for both links is 15 upwards (to the front). Pinion angle is measured between the pinion gear flange and the driveshaft. on rough race tracks. The length of the upper links should be at least 17" . This induces less rear steer when the car squats on exit. The company offers a wide array of quality chassis components at reasonable prices. Rayburn of Rayburn Race Cars, a driver as well as a car builder, echoed much of what the other buiders had to say. Notice how this
These bars are used to center the wheels in the wheel well and to set the wheelbase from side to side. . Adaskaveg got his start working for track photographer Lloyd Burnham at Connecticuts Stafford Motor Speedway in 1970. A triangulated four-link puts the instant center (I/C) locationthe imaginary point of where the rear suspension components intersect, and the point theyrotate around in a given (instant) positionway out front, often close to the engine. Increase Left Rear Spring Rate. bottom links further as shown in illustration 2C. to enhance the forward bite. These are BMR upper trailing arms for 1979-2001 Mustangs. Welcome Guest. Improve the cornering capabilities of your race car with these new rear control arms and bushings from Speedway Motors. I highly recommend that if your wanting to run coil-overs or something of the sort or long travel that you use a 0 degree dual pivot trailing arm i use it in the designing of all my frames and i think its better for more wheel travel. you will speed up your learning process by working with a model. This has been confirmed by studying data from onboard computer systems during testing that show shock travel amounts in the turns. - Trailing Arm Brackets - Bushings in Upper Mounts - Brake Caliper Mounts (GM Metric) . move the
SourceA & A ManufacturingSpring Lake, Michigan800-473-1730aa-mfg.com. initial forward bite. birdcages during chassis roll. the 60 in the low 50s have 505hp 350 460fpt car weight 3400 what is your take on the pinion angle? If the car has OEM style rubber suspension bushings, a pinion angle of minus three to minus four degrees is more appropriate. Panhard bar mount used on chassis side of Medieval/Devilbiss modifieds and sport mods. There can be a small amount of rear steer as the chassis rolls and squats, but it is both minimal and mostly fixed as far as adjustability.