He uses his knowledge as a racer to continue to innovate his chassis designs. My car had 7Deg of angle it. KT-1A). The Z-link rear suspension, or swing arm as it is also known, is another system used on dirt cars. Adjustable lower bars are used to center the tires front to back in the wheel well and to make small wheelbase changes. 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. Simply replace the slug with different combination of offset slugs. mounted 15 upwards to the front. 2- 175-C bushing for upper mounts. but there are ways to get that back. 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. A drag race style anti-roll bar is a key ingredient to making your triangulated four-link work. This kit is affordable for most street stock racers, and it is both easy-to-install and easy-to-use, Nolff said. Photo courtesy of Hotchkis Suspension. on rough race tracks. The first element to understand about rear steer is that it is caused by rear suspension movement. It helps prevent the mounting points from tearing out when the suspension is shocked during a starting line launch. shortened bottom link. The technology related to rear steer for asphalt and dirt are somewhat different. Welcome Guest. Trailing Arm Brackets shocks and springs. Wehrs Body Bolt Panel Inserts. The Standard 4-Bar System Designed for stock cars with a 7.5 max trailing arm length. The company offers a wide array of quality chassis components at reasonable prices. Improve the cornering capabilities of your race car with these new rear control arms and bushings from Speedway Motors. Hes owned his own speed shop, built race cars, street rods, and custom motorcycles, and restored muscle cars. LZ-13-B) from 3/16-thick steel. 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. This condition will cause loose handling-especially The track in this case was banked and had a lot of grip. 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. 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. It takes less than two hours for an experienced welder to install the kit.. Tack weld the slugs to secure them to the trailing arm. Notice, in illustration 2D, starting point for both links is 15 upwards (to the front). coil-over units directly to the axle housing. 4. Kit contains: (2) Rear upper control . 2-4 Offset Bushings and Trailing Arms. Thats not necessarily bad. When Rear steer can either tighten a car or make it very loose. They are angled to fit GM Metric chassis and have four holes for racers to adjust their trailing arm position. My upper a arm is at a 10 degree angle pointing down towards the front. Obviously, if both of the wheels did not move, or moved in the same direction by the same amount, we would have zero rear steer. The rule about never steering the rear end to the right on an asphalt car does not apply on a dirt car. with the very soft chassis meaning floppy front subframe is 4.5 enough? For example, you want the top link to be perpendicular to the rear end housing and parallel to the car. loading of the rear tires. 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 . 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. Dave here in Saskatoon been racing a g body for many years now and struggle to get I like to see a 1" long weld on the top inside of the right side. right and 10 to 15 on the left provide good forward bite. It has been a practice for teams to align the rear end-and/or have it steer slightly to the right-to fix a tight mid-corner condition, but this goes into the category of crutches, and should not be necessary if the car is set up properly otherwise. Shock brackets (part No. forward on the left side during chassis roll. Phone (07) 31033011 Between - 9:30am - 4:30pm. This has been confirmed by studying data from onboard computer systems during testing that show shock travel amounts in the turns. lowered the bottom links to a level position and now the bottom of the Part No. Some forward bite may be lost when Metric Chassis Complete A-Arm Assembly $ 99.95; Camaro Chassis A-Arm Shaft Assembly $ 99.95; JOES 24" Pit Steering Wheel $ 199.95; Useful . These notes are based on the Directorate General of Shipping Syllabus for the three month pre sea course for deck cadets 60 offset new reproduction stamping Ford 9 housing with new 3 tubes and GN hub type snouts. to -mile numbers by multiplying by 1.54. To understand how a 4-link can be A racer himself, he was the winner of the Street Stock Nationals in 2019. The advantage of this system is that it keeps the rear end squared up and the thrust under acceleration straight ahead, if that is what is needed. 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. Adaskaveg got his start working for track photographer Lloyd Burnham at Connecticuts Stafford Motor Speedway in 1970. AA-384-B and AA-384-C), made from 3/16-thick steel, sit on the back of the lower trailing arm mounts. just ordered the adjustable lowers My trailing arms are stock triangulation. 60 GN 1R offset MAXIMUM aftermarket Ford 9 housing with new 3 OD tubes and 2.5 GN hub snouts. This arrangement: * puts the instantaneous center 199 inches from center of car. attention to how the lower link adjustments change the paths traveled by clamp brackets to mount the left coil-over unit ahead of the axle I want just for street use, nothing but just Soft Ride. PCE Midnight Series Entertainment - a quality range of Industry Commando / Ceeform Plugs and Sockets widely used in the live events, film, TV and theatrical industries. springs). On the left side, the bottom Asphalt stock cars have four predominant rear suspension systems and all of them produce some amount of rear steer. They constantly introduce new products to their lineup. The key to correctly The bars can be mounted on one side of the car so that only that wheel moves to create the rear steer. Trailing arms must also be running forward at the correct car builder design angle. From personal experience, theyre great quality. Looking for that edge over everyone else. currently using 4.5 down and it picked up 60. There are limits to how far we go in steering the car this way. RAceman. OUT OF STOCK until appox. using stock coil springs new .have adjustable uppers and This bracket is also built heavy, weighs 7.5lbs (with slugs) to help increase LR rear end weight. cause a gas pedal push. The difference is, Id like to use the center post where the three link top link currently attaches to the chassis, and go out to brackets at the ends of the rear axle. A lot of guys take that to extremes.". Stock trailing arm kit, used for mounting Ford 9 in GM metric car. - Trailing Arm Brackets - Bushings in Upper Mounts - Brake Caliper Mounts (GM Metric) . Change your lead or trail of the rear end by simply changing the combination of offset slugs. That saved the factory some money. very stiff. 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. 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 . A well designed 4-link provides good forward bite and the proper the right side Dual internal gusseting provides strongest rear end in the industry. If excessive, loose roll steer can cause a loose Depending on the angles of the trailing arms or bars, each rear wheel can be made to move to the front or rear. (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. 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 can reduce I have edelbrock adjustable uppers with non adjustable boxed lowers. The front locating points must be in the stock locations. Under the wrong conditions, it can ruin your handling. He uses his knowledge as a racer to continue to innovate his chassis designs. (Steel). forward bite and roll steer. . Distance from link mounts to transmission output and 3'rd yoke will dictate mount position. . The trailing arm side will be rusty and wont remove easily, I had to unscrew mine with a 3' breaker bar! Keith Masters of MasterSbilt Race Car Chassis said, "The reason chassis builders build 4-bar cars is because of rear steer. This clamp on trailing arm mount is for the GM metric chassis lower bars. Some will say run them as low to the rearend housing as you can. Trailing arms mounted in this manner cause the rear tires to adjustment, positioning the lower links 5downhill, causes the bottom of The rear will have Viking coil over shocks . 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. The variation of height for the right-rear trailing arm is very small. Wehrs Modified Valance Support. Finally, Im not exactly sure what you mean by a floppy front subframe. 4-link, or use the design parameters mentioned in this article, to help Those conditions rarely exist on dirt. One of the things we have done, is to raise the rear ride height. priority to have the trailing arm brackets and top link hardware to be located in the proper location. An anti-roll (or anti-sway) bar is most often used to preload a triangulated four-link. Compared to the 4-bar cars, it has more limited adjustment for rear steer and historically has worked well on the tighter and more highly banked race tracks because the rear end is pointed more straight ahead. 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. Condition: New. unloading of the rear tires during deceleration This unloading can upset Consequently, a further reduction in loose roll steer results. 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. two factors. Then, a 1" weld on the bottom inside of the left side." links have to be extremely short to minimize loose roll steer. 4AN To for 8mm X 1.0 Metric Straight Adapter Vibrant. Departing from Ho Chi Minh City. Add a good weld-on ARB out back. Long bottom links (equal in length or no more than 1 Skip to main content. This promotes forward bite without causing the car to be tight on entry or in the middle of the turns. The RR lower most will run level. But as youll see in the photos, adjustable trailing arms are the firstand bestmethod of setting up a triangulated four-link for drag racing. 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. This one is made by Hotchkis for GM A-body cars. There can be a handling trade-off, however, to the forward traction BMS Racecars - Winning's not just a goal it's a tradition! Under most current rules, there is no adjustment for amounts of rear steer with these systems. 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. Putting the stock "W" style suspension into a bind is your biggest enemy. From a structural standpoint, tubular trailing arms are much stronger than factory trailing arms. 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. You may be required to make chassis adjustments to Order your Trailing Arm 2 Piece Set - today at 1AAuto.com. The rear axle (Try to bounce the rear of a car with a 4-link rear Add to cart Details. 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. 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. Remove only one control arm at a time. Adjust the length of the control arms as needed to achieve the desired pinion angle. To help understand the Instant Center you can visualize a triangle (Fig. Upper link angles from 15 to 18 on the Ground clearance at bump and uptravel at ride height will dictate link angle. Decrease RR Trailing Arm length by 1/8 inch. what wold be the best angles to be at for most foward bite along with handling four all four links ? Then this trailing arm bracket kit is a must have. We stated earlier that trailing arms mounted upwards to the front of And have fun at SIR! Bushings in Upper Mounts reducing loose roll steer. How Much is Too Much? gained by running the trailing arms upward to the front of the race car. 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. KT-1B) makes removing a GM rear end from a GM Metric chassis much easier. JavaScript is disabled. (during acceleration) is quickened and forward bite is enhanced. Wayne 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. and rearward (R.S.) With this system, the rear end stays located by virtue of the opposing angles of the upper and lower links. Required fields are marked *. taken off 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. 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 . These arms also use rod ends on each end to prevent binding when under load. 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. Performance Disc Brake . Increase All Shocks rebound and compression, but rebound should always be higher than compression. The lower links are angled from a top view with the front pivots narrower than the rear pivots. 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. Make small adjustments if you feel a need. AA-175-C). Has a 1/4 hole on bottom to allow bolting to your weight jack bolt. My lower trailing arm is level. Wehrs Bent Suspension Bar Angle Finder. the race car enhance forward bite by using axle thrust to quicken the $15.75. KT-1B) sells for $96.00. The Setup with Shane Tesch Topic - Center Pull #shorttrackracing #metalfabricator #latemodelstockcar #metalfabrication #chassisfab #stockcar #metalfab #motorsports #portcityracecars #superlatemodel #chassis #racecar #asphaltracing #pavementracing #racingparts positioned ahead of the axle and attached to The RR lower most will run . suspension moves (unless both upper and lower links are equal in length ability to let the race car turn freely in the middle of the corner There are reports from the past of a team winning a race using four 400-pound springs on a Z-link type of car. Most Street Stock rules wont let you change the frame mounting positions so all you have left is the rear end mounts. Location. Most often, the factory trailing arms are simply a stamped metal arm. Additional washer added on end to extended life of bushing in severe conditions. These bars are used to center the wheels in the wheel well and to set the wheelbase from side to side. birdcages and mounted to Cf: a c t i v i t . 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. (on a clamp bracket) generally tightens corner handling. With stock brackets on . Large 1 NPT fill plug installed for easy filling or connecting to fill tank. 60 offset new reproduction stamping Ford 9 housing with new 3 tubes and GN hub type snouts. Thanks so much! These systems only steer to the left and have a limited amount of steer. Hotchkis and Global West make similar control arms for Mustangs and GM A- and G-bodies. These trailing arm brackets use common offset slugs (sold separately) to allow you to change the amount of lead or trail in the rear end. Which ones do you recommend? In a high horsepower car, engine torque tends to rotate the car so the right rear tire has more bite. So, teams need to take this rate difference into account. 2.50 from axle tube to center of hole. try to drive underneath the chassis as the rear axle pushes the race car birdcage does lose some of its rearward movement because of the Wayne If you dont do anythinig else. When selecting springs for your 4-link, you should bottom link arrangement of illustration 2C on the left side and the This bolt on upper trailing arm mount is designed to allow use of a quick change into a stock GM metric chassis. The Z-link System 2.5 drop trailing arm brackets slotted to accept offset slugs. 1-1/2 Tube Diameter Clamp For Limit Chains on Chassis Side, 1-3/4 Tube Diameter Clamp For Limit Chains on Chassis Side. The front may be too stiff compared to the rear. Lowering the car changes the sprung mounting points (body/chassis) but not the unsprung (axle) mounting points. Oct 12, 2013 #2. where the chassis tends to push. Then this NEW trailing arm bracket kit is a must have. stop and go or slick race tracks. clamp brackets. [3] Advantages of Trailing Arm with Camber Links 2. Compare the measurements to specifications. birdcages, to rotate against the shocks and springs during Keep in mind that any change to the Built with corrected pinion angle and our proven "Pull" Bushings. If you need brake brackets, A & A Manufacturing manufactures both GM Metric caliper mounts (part numbers starting with AA-113) and big GM mounts (part numbers starting with AA-049), with pricing ranging from $9.82 to $15.84 per bracket. This induces rear steer when the car squats on exit. Semi-trailing arm suspension, handling and stability performance, non-linear vehicle model, Bees algorithm Date received: 17 November 2011; accepted: 3 February 2012 Introduction On the left, we have reduced the forward movement of birdcage moves forward during chassis roll instead of rearward as in clamp brackets are used in front of the axle, axle wrap-up during 2,224. 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. LR bracket is 6.75 from axle tube to center of bottom hole. Can be used on both 9" Ford and quick change rear end tubes. Learn how your comment data is processed. the race car upon corner entry -especially when both coil-over units are Rear steer in this system is caused by chassis movement, which can . This induces less rear steer when the car squats on exit. Realize that you can increase forward bite on any type of rear shorter than the upper links) work best for fast tracks or on any track The company manufactures the kits lower trailing arm mounts (part No. On most flat- to medium-banked tracks, the left-rear moves very little. Show more About this course $299.00; 160 lessons . Instead of using some form of track locator or Watts linkage, the trailing arm triangluation keeps the rear end properly located in the car. Adjust Cross Weight as changes are made to keep the car neutral. 650 whp. Has a 1/4 hole on bottom to allow bolting to your weight jack bolt. path traveled by any trailing arm will affect roll steer. The 4-bar suspension is highly adjustable and can be made to steer both directions. Usually, the right-rear corner of the chassis moves more than the left-rear. The asphalt racing surface provides a lot of traction, even on those flat "slick" tracks. Simply replace the LR bracket and have increase drive and adjustability. SportMod jigged. However, keep in mind that chassis roll causes the link angles to forward (See illustration 1). Followed your advice and got a set of adjustable lowers. In dirt racing, it may be advantageous to incorporate a large amount of rear steer under certain conditions. the bottom links are lowered but the effect on forward bite is usually A smooth entry provides a faster exit. As a result, we reduced loose AA-621-A fits 3 axle tubes $14.95. Tuning With Rear Steer KT-1A ). shocks are compressed from both ends at once and the suspension becomes In short The lowest rear RC you can get is with all arms parallel to the ground (no angle) . Tack weld these washers to the outer flange of your bushing to create a retainer for the rubber. Hi DaveGlad to help if I can. This action will cause 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. MAXIMUM Performance right side climbing panhard mount for quick change rear ends. Designed for the Wissota street stocks, these trailing arm brackets have the lowest mounting hole position possible. This year marks the Outside Groove Director of Photographys 51st year of covering auto racing. You can lengthen or shorten the bar by loosening the jam nuts on either end and turning the adjuster. 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. Housings have fill and drain plug installed. this important function of the lower links. right side link is from 3 to 5 higher than the left when the chassis Any of you guys changed any angles on trailing arms etc on a metric to make it faster? 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. 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. about rear suspensions. This produces quite a bit of rear steer to the right, moving the rear of the car to the right, just like when we used to throw the car sideways. When one wheel moves more than the other, we have a certain amount of rear steer. Rear steer amounts-due to the Panhard bar angle-are regulated by the angle. Im assuming youre referring to the front end more below: Cars with a lot of twist and bind are difficult, if not impossible to tune. to enhance the forward bite. forward(L.S.) However, indexing can cause the rear suspension to be too harsh Rayburn builds the swing-arm type of rear suspension. See the text for more information. the indexing and the link angle changes during roll or bump. 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. Assembly includes: 2.5 MAXIMUM GN hubs, hub bearings, seals, brake rotor, drive flange, axles and all hardware necessary. Adjustable arms allow easy rear suspension . 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. Tack weld the slugs to secure them to the trailing arm. clamp brackets during acceleration will be accompanied by an These stamped metric style control arms are great replacements for twisted or worn out rear upper arms on your GM G-Body. sensitive to adjustments. tuning a 4-link, it is important to understand the relationship between suspension is to shorten the bottom links. I am dropping my ride height 2. Again the height of the mounts are critical as to the resultant force transmitted. The length of the upper links should be at least 17" . Clamp Brackets are used to mount the 4AN To for 8mm X 1.0 Metric Straight Adapter Vibrant. designing and tuning a 4 link is to understand the significance of these Jul 23, 2001. Wehrs Body Braces. are used to help control loose steer. These conditions call for a driving line that is more straight ahead. Description. during acceleration (due to the axle thrust effect). Characteristics of the metric 4-link, one of those four, are the same as discussed under the heading related to asphalt cars. Pinion angle is measured between the pinion gear flange and the driveshaft. Custom Part is Non-Returnable and Non-Refundable. length and/or angle difference in the upper and lower links. On cars with triangulated upper control arms, you cant set preload with adjustable arms. Trailing arm bushings come included (part No. . The trailing arms can be mounted parallel to the centerline of the car, or angled with the front mounts closer to centerline. Currently my model has: * the lower control arm is angled up from ball joint to pivot at 4.1 degrees. Balance the Front and Rear stiffness. 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. 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. Brake Caliper Mounts (GM Metric), Spring Perches & Shock Mounts (Kit or Welded). Mounts J-Bar to 9 third-member 4 3/8 offset from pinion. $149.99; 149 - Reward points. Clamp brackets are sometimes used on short, slick tracks to improve A 4-link Decrease LR Shock rebound and/or increase RF Shock compresion. Lower the Rear Panhard Bar on both sides (frame and rear-end attachment). But the 60 in the low 50s have 505hp 350 460fpt car weight 3400 what is your take on the pinion angle? Since drive line angles can change if you adjust your ride height, your pinion angle may need to be adjusted. After subframe support arm is out of the way, unscrew the . 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. . Keep in mind that trailing arm angles can become excessive if the rear of the chassis lifts a lot during acceleration. Decrease the Rear Weight Bias. The Impala spindles are the " hot set up " on a metric chassis. suspension moves. Mounting the left coil-over unit ahead of the axle If you want to insert bushings with a press rather than a mallet, opt for part No. If the link angles become more upward on the left than on the During chassis roll, trailing arm/s mounted upwards will cause the right Matt, We use the upper links on a 4-link suspension clamp brackets and ahead of the axle can improve forward bite on Description : General Motors 64-67 "A-Body" Adjustable/Indestructible Rear Control Arm Upper Cross Member! 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.
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