Frame Setup & Installation Instructions GM A-Body

Transcription

1 Frame Setup & Installation Instructions GM A-Body

2 2 Table of Contents Introduction... 3 Body Mounting... 3 Engine Fitment... 4 Transmission Fitment... 4 Steering Column & Linkage... 4 Brake Lines... 5 Wheels & Tires... 5 Axle Housings... 6 Frame Fit and OEM Tolerances... 6 Frame & Component Installation & Setup... 6 Alignment Specifications... 8 Post-Drive Checklist... 8 Important: Lifting a Vehicle with Two-Post Lifts Chevelle Wheel Size and Offset Specs mm Front/255mm Rear Tire Example mm Front/355mm Rear Tire Example mm Front/275mm Rear Tire Example mm Front/335mm Rear Tire Example Steering Rack Technical Information DSE/Mustang Rack Steering Stop Information Steering Shaft Support Kit for Big Block Cars Rear Coilover Installation Rear Sway Bar Bushing Installation Rear Sway Bar Installation Front Sway Bar Installation Steering Arm Installation Front Lower Control Arm Installation Front Upper Control Arm Installation Optional Equipment: Stainless Brake Line Kit Optional Equipment: Brake Proportioning Valve Mount Kit Optional Equipment: Polyurethane LS Motor Mount Adapter Kit Optional Equipment: Rubber LS Motor Mount Adapter Kit Optional Equipment: Axle Housing Vent Kit Fastener Information & Torque Specifications... 40

3 3 Introduction Congratulations on the purchase of your Art Morrison Enterprises GT Sport chassis. This frame is the result of many years of chassis and suspension design experience. In an effort to make your project progress smoothly, we have compiled this booklet containing instructions, notes and tips on removal of your current frame as well as assembly and installation of your new GT Sport chassis. Art Morrison Enterprises Engineering department has chosen C6/7 knuckles for their superior strength, design and aftermarket support. Simply using C6/7 parts, however, will not guarantee the best performance. Countless hours were spent utilizing computer modeling and analysis to ensure the suspension provided on this frame provides excellent performance yet fits the packaging necessary on A-bodies. The GT Sport frames follow the Art Morrison design philosophy that combines simplicity and elegance. We believe stiffening material and bracing should only be added as necessary because too much only leads to additional weight. High stiffness can be obtained by geometric design rather than adding material. The GT Sport chassis uses a fully boxed mid-rail section with strategically placed bracing that connects to a 2x3 underfloor structure. The cross bracing has the option to bolt to the body s stiffening ribs if desired. Unlike stock frames, this frame makes use of 3/16 wall front 2x4 rails to combat a common weakness in A- Bodies front frame sag. Body Mounting The Art Morrison GT Sport chassis is a bolt-on frame, meaning it bolts to the body as the original frame did. Please refer to a Fisher Body Manual for removal and assembly instructions. Various body mount solutions are available for A-bodies and any kit produced for a stock chassis will work on a GT Sport frame. Body mount kits typically vary by material, from soft materials such as rubber to harder materials such as aluminum. All material options have their merits. Rubber body mounts can isolate vibrations and offer a quiet cabin, similar to modern cars. These mounts however, act as a secondary spring between the suspension and body and add body flex. People looking for a quiet, vibration free cabin should look into using rubber mounts. Those who are looking for performance or running tight fender gaps should use harder materials.

4 4 Polyurethane and aluminum mounts can be grouped into the same category as their compressed stiffness is fairly similar. Polyurethane mounts will isolate high frequency vibrations (which cause high pitched rattles) slightly better than aluminum. However, aluminum mounts have the advantage of being highly accurate and are ideal for high performance vehicles or those with tight fender gaps. Because of the zero compressibility of aluminum mounts, consider running medium strength thread locker on the body bolts. Engine Fitment Your new GT Sport frame will accept small block, big block and LS-series Chevrolet engines. The engine frame mounts are a multi-position design to move big block engines forward to clear the firewall, while all others move the engine as far back as possible to optimize weight balance. Stock frame configuration offsets engines to the passenger side which makes room for steering boxes and power brake boosters; however since a steering box is no longer utilized the engine has been centered within the vehicle. This may require the use of a smaller power brake booster or an alternative method of power brake assistance. For proper fitment LS engines require the use of adapter plates available only from Art Morrison Enterprises; the utilization of adapter plates from other manufacturers may generate clearance issues. LS F-Body engine accessories (including A/C compressors) will typically fit within the frame rails. Corvette, GTO, CTS and truck accessory configurations will also fit. When shopping for an aftermarket drive system, pay particular attention to the area left of the engine oil pan as this is where the steering rack will reside. The engine oil pan design is critical for proper performance as well as trouble-free installation. Due to the steering rack location, oil pans typically will need to have a minimum front depth. For small and big blocks, traditional front pan depths (similar to stock) will be adequate. For LS engines, choose a pan that is similar to a F-Body or LS2/LS3 oil pan. For reference, front pan depths should be around 1-7/8. Transmission Fitment The GT Sport frame is designed to support modern manual and automatic transmissions. Manual transmissions will require the use of a hydraulic throwout bearing as Z-bars are not supported. Due to the size of modern transmissions, there is a possibility of requiring the transmission tunnel to be modified. In general, transmissions requiring tunnel modification on stock chassis cars will be the same with a GT Sport frame as engine mount locations are very similar. If using a new transmission that does not yet have aftermarket support, a custom crossmember may be required. Steering Column & Linkage To use the stock steering column a rag joint adapter must be attached onto the column end to accommodate a universal joint. Due to this process, some stock steering columns may have an interference problem between the universal joint and the frame rail and can be solved by using an aftermarket column that is shorter in length.

5 5 An aftermarket steering column should be utilized for several reasons. First, the column can be ordered in any length for maximum flexibility. Second, the welcome addition of a tilt feature and all new components as well as zero steering shaft radial play, makes these columns a convenient choice. Third, they feature a 1 double-d end for easy linkage hook-up. Lastly, most manufacturers offer steering columns that are 2 diameter which allows you to reuse the factory firewall mount and optional dash mounts for a true bolt-in installation. An AME steering linkage kit provides you with all the necessary parts to connect an aftermarket column to the steering rack is available from Art Morrison Enterprises. Big block engines will require a support bearing available from Art Morrison Enterprises to provide additional header tube clearance. Brake Lines Art Morrison Enterprises offers a brake line kit to make this task easy and includes all necessary fittings and clamps to provide fluid to the brake calipers. Due to the variety of braking systems, a short line will need to be fabricated from the master cylinder (or combination valve) to the front line kit. All line kits are made from 304 stainless steel and feature -03AN fittings with all stainless hardware. Wheels & Tires While the GT Sport s hub track is similar to stock, there are other considerations to examine before using wheels for a stock chassis. First, the brakes used on a GT Sport chassis requires close attention regarding overall diameter and caliper offset. Second, the chassis will lower the car much more than stock and typically will require slightly more positive offset. While Art Morrison Enterprises has gone to great lengths to ensure proper wheel and tire fitment, variations can occur from vehicle assembly or modifications/repairs over the years that affect fitment. Backspacing and proper fitment should be double checked before ordering wheels! The distance between inner rear tire to inner rear tire must be 48-3/4 or greater if minitubs are not used cars must not have an outer bulge width greater than 70 if the fender lips are not trimmed, and no more than 70-5/8 if the fender is trimmed at the 3:00 and 9:00 positions models can accept a 255mm rear tire without minitubs assuming the frame is precisely centered in the body cars have a wider rear fender width, and can accept a 275mm rear tire without minitubs. Without trimming fender lips, outer bulge width can be up to 70-1/2, and no more than 73 if the lip is trimmed. All years can accept 335mm tires if using minitubs but pay careful attention to the body mount just behind the rear tire. Depending on the diameter of the tire this mount may need to be modified or removed. Up front, a 275mm tire can be used with steering stops. Depending on the diameter of the tire and final ride height, some inner front fender modifications may be required. Buick/Olds/Pontiacs may have wider front and rear fenders. Please double check measurements with these cars to ensure the wheels are ordered correctly the first time.

6 6 Axle Housings When ordering a GT Sport frame, several axle housing options are available. To make selection simple the housing width can be specified to replicate stock, 3 narrow, or a custom width. All axle housings are a modern rendition of a Ford 9 design. These housings include a brand new stamped center section (Fab 9 is optional), 3 diameter 3/16 wall axle tubes, and forged tube ends. All housings are built on a precise fixture that ensures proper wheel alignment. Frame Fit and OEM Tolerances Art Morrison Enterprises has done extensive testing to ensure the frame matches OEM specifications while maintaining much tighter tolerances than GM s specifications as produced over 45 years ago. Over the years, these vehicles have been subjected to high miles, accidents, racing and lastly, time. Many of these vehicles have been in accidents but the damage from which is no longer readily evident, however these incidents may have severely distorted the location of body mounts. Even low mileage, pristine survivor cars can suffer from body sag due to uneven spring settling. Due to these factors, the body mounts located on the frame may be slightly different than those on the body shell. This is considered normal, and is often not an issue thanks to a large amount of adjustability. When fitting the frame to the body, shimming the body mounts is recommended if a precise fit is desired. Buick/Olds/Pontiacs, El Camino and Wagon frames are 3-1/4 longer in the rear section between the second-tolast body mount and the rear bumper mount. Please note some BOP A-bodies are 120 wheelbase and the GT Sport frame is only available in 115. Frame & Component Installation & Setup Frame removal and installation follow identical procedures between the stock frame and GT Sport frame. Refer to the factory shop manuals for procedures and torque settings. Prior to assembling the frame to body, all brake lines, fuel lines, parking brake cables, etc. should be attached. To prevent interference later, it is imperative to be mindful of where the engine and headers will sit. Prior to finishing, the frame should be disassembled. As the frame is assembled at Art Morrison Enterprises the front and rear suspension is pre-set to initial alignment specifications as a quality check. To maintain these settings, prior to getting the car aligned, be sure to take measurements of upper control arm shims and tie rod lengths. Ideally, all welding and drilling should be completed prior to powdercoating or painting. Please note that all welds must not be ground smooth as this will weaken the frame s structural integrity. If you wish to have the welds smoothed use body filler instead.

7 7 After the finishing operation has been completed the frame can now be assembled. Set the frame on a level surface in a well-lit area. Next, use a rat-tail file to clean all holes which bolts pass through and make sure all threaded bosses are clear of powder or paint. To finish the preparation process, collect all fasteners and have the torque specifications sheet handy. To begin assembling, install the upper control arm/knuckle/lower control arm assembly by first fastening the lower control arm bolts to the frame. Next, bolt the upper control arm to the frame ensuring that the alignment bushings lay between the two. Hand-tighten all fasteners for now and repeat the process on the opposite side. Now, install the steering rack with the fasteners, hand-tighten and attach the tie rod end to the knuckle. To install the sway bar, first attach the end linkage to the bar using the drawing as a guide. Then attach the linkage to the control arm and rotate the bar toward the bottom of the frame for attachment. To mount the coilovers, attach the lower mount to the control arm with the provided fasteners and then attach the upper mount to the chassis. As a starting point, set the coil spring adjuster to 1 above the lowest adjustment point. When plumbing the steering rack, note the fitting closest to the radiator is the pressure line and the other is the return. To start the bleeding process, first fill the reservoir full of power steering fluid. With the reservoir cap removed and the wheels off the ground, turn the steering wheel lock-to-lock twenty times while monitoring the fluid level. When complete, the engine can be started and checked for leaks. Before driving for the first time, rotate the steering wheel another four times. See the Steering Rack Technical Guide later in this manual for other important information. To complete the assembly process attach any brake lines, brackets, transmission crossmember and other necessary components. Check every fastener for proper torque and mark with a paint pen as a visual indicator. If you purchased the optional Wilwood brake kit it is imperative the break-in procedure be followed very carefully. Failure to follow these directions will lead to glazed pads and poor braking performance. If these directions are missing from your brake kit, visit to download their instructions.

8 8 Street Settings Toe: 1/32 to 1/16 total (in) Camber: ½ to ¾ degree negative Caster: 4-1/2 degrees positive Alignment Specifications Autocross Settings: Toe: 0 to 1/16 total (out) Camber: 1-3/4 degree (Consult tire manufacturer) Caster: 4-1/2 degrees positive Road Course Settings: Toe: 0 to 1/32 total (in) Camber: 1-1/2 degree negative (Consult tire manufacturer) Caster: 4-1/2 degrees positive Post-Drive Checklist After the first 100 miles, please check these items: 1. All fasteners (including wheel lugs) 2. Brake fluid (Fluid level and check fittings for leaks) 3. Power steering fluid (Fluid level and check fittings for leaks) 4. Coolant (Fluid level and check fittings for leaks)) 5. Transmission fluid (if applicable) 6. Fuel lines (Check fittings for leaks) 7. Brake Lines (Check fittings for leaks) 8. Battery cables 9. Exhaust system The coil springs should also be checked and readjusted if necessary. New springs will typically settle once after several miles and usually do not need a second adjustment.

9 9 Important: Lifting a Vehicle with Two-Post Lifts The debate of choosing a four or two post lift is something that many can have strong opinions about. While driving the vehicle onto a four post lift is convenient, it comes at a cost of requiring another lifting assembly to raise the vehicle off of the ramps in order to remove the wheels and perform any brake or suspension work. Two post lifts solve this problem by lifting the vehicle by the frame or reinforced unibody structures. However, the problem will arise with a two-post in which the vehicle is lifted unnaturally, meaning loads are placed in areas that will cause some beaming flex. This type of flex is a function of frame stiffness and body stiffness, with the frame stiffness is typically 30-40% of the total beaming stiffness. Vehicles with heavy drivetrains will increase flex, as the majority of this weight (engines and axle housings) are far away from the lifting points. It should be noted that this flex is completely normal. Dealerships and OEMs use two posts lift which should be a testament to their safety. However, this issue can become a problem with vehicles with precision door gaps that are tighter than typical OEM specifications or body panels that have been modified or removed for larger engines, aesthetics, etc. Panels and doors should always be fitted with the vehicle on the ground or the frame properly supported in some way. Convertibles will always see much more flex than coupes and sedans, to the point that doors may not open or shut. In most cases, the older the vehicle, the higher probability for flex as body stiffness increased with newer vehicle designs with more stringent safety standards. While beaming flex may be alarming to some people, this does not mean the vehicle won t drive correctly. As mentioned before, it s simply loading the vehicle in an unnatural way. Vehicles are meant to be driven with the normal road force applied to the vehicle s suspension, not applied to the area below the rocker panels. Loading the vehicle properly allows the forces to be efficiently transmitted through bracing and body panels with the upper areas in compression, whereas loading at the rocker loads these areas in tension with the drivetrain and suspension acting as ballast which encourages flex. In summary, beaming flex is a normal occurrence when using two post lifts. Vehicles of all types, new or old, full frame or unibody, coupes/sedans and convertibles, will flex. The magnitude of this flex depends on vehicle age, condition, construction, design, drivetrain weight, and lastly the lifting point spread all of which is to be expected.

10 Chevelle Wheel Size and Offset Specs Rear Wheel Dimensions With a bare housing widths shown below, the rim width and backspace dimensions that will fit correctly are as follows: Housing Width 54-5/8" 51-5/8" Max Rim Width: 12" 12" Max Section width: 13-1/2" 13-1/2" Backspace: 7-7/8" 6-3/8" Other sizes: 275mm on 9" wide rim with 5" (stock HSG) / 3.5" (narrow HSG) backspace 295mm on 11" wide rim with 6-3/4" (stock HSG) / 5-1/4" (narrow HSG) backspace Front Wheel Dimensions (18 minimum) 275mm on 9" wide rim with 6" backspace (64-65) or 5.75 backspace (66-67) 245mm on 8" wide rim with 5" backspace (64-65) or 4.75 backspace (66-67) Note: Steering stops likely to be required on front wheels wider than 8 Brake Clearance Due to the Corvette knuckle and hub assembly, precautions MUST be taken to ensure the wheel will clear the brake caliper. Unlike older brake systems, the outside face of the caliper is 1.27 past the wheel mount surface. If using aftermarket brakes, please follow the manufacturer s recommendation for proper clearance.

11 mm Front/255mm Rear Tire Example

12 mm Front/355mm Rear Tire Example

13 mm Front/275mm Rear Tire Example

14 mm Front/335mm Rear Tire Example

15 15 Steering Rack Technical Information Hoses For those using -06AN hoses, AME can supply the proper fittings. Be aware that some aftermarket fittings do not use the correct threads and can damage the casting. Before installing, coat the O-ring with power steering fluid and torque the fitting to 20 lb-ft. The return hose can be any type of low-pressure hydraulic hose. The pressure hose can exhibit pressures above 1500PSI and requires a high pressure hose. We do not recommend the use of any stainless steel braided/teflon lined hose for its inability to dampen hydraulic chatter, thus creating a growl sound when turning the steering wheel. To keep this noise to a minimum, use a hose with a rubber length of 15 or more. The pressure fitting on the rack casting is the fitting closest to the front of the vehicle (lower fitting), and the return fitting is the closest to the firewall (upper fitting). Rack Centering It is easier to center the steering rack before mounting the unit to the chassis. To center the rack, turn the pinion to full lock and measure between any point on the rack body to the end of the tie rod in the extended direction. Divide this distance by two, and rotate the pinion in the opposite direction until this distance is reached. The rack is now centered. Using a paint pen, mark the pinion s location on the seal or housing so the rack can be re-centered if moved later. Mounting All Mustang-type steering racks mount using 5/8 -NF x 3.5 bolts when using an Art Morrison chassis. Be sure to liberally coat the threads with anti-seize before installing. Torque bolts to 50 lb-ft. When using rebuilt steering racks, end boots may be loosened and rotated to move the 3/16 equalizer tube to a different location if more clearance is needed. Tuning Both steering racks respond well to fluid flow rates between 2 to 3 gallons per minute. Less flow tends to increase steering effort, but too little may lead to pump catch where power steering assist momentarily stops until the pump can catch up to the required fluid flow. Too much flow may lead to a steering feel that is too light and possibly twitchy. Some power steering pumps have adjustable flow rates, while most OEM type pumps do not. If you feel the fluid flow rate may be too high, contact Art Morrison Enterprises for a valve that will allow approximately 2 gallons per minute of fluid flow.

16 16 Keep in mind that pumps originally used for steering boxes typically have higher pressure and flow rates than what is required for steering racks. If your pump provides too much pressure, fluid may escape past seals in the steering rack and cause a failure, particularly with rebuilt steering racks. Art Morrison Enterprises has a pressure reducing kit to correct these situations. For cars using wide tires, Art Morrison Enterprises can supply steering stops that snap on to the rack shaft with the boots removed. This provides a simple way to limit steering travel for cars with interference issues. Bleeding Procedure (Important! Do not skip this procedure!) 1. Place the front end of the vehicle on jack stands and remove drive belt. 2. Fill reservoir with high quality power steering fluid and rotate the pump pulley by hand for about thirty seconds. 3. Have a second person rotate the steering wheel from lock to lock, about thirty times, while continuing to rotate the power steering pump pulley by hand. Watch the fluid reservoir to make sure it does not run dry. 4. Install the drive belt and start the engine. Continue to rotate the steering wheel from lock to lock about fifteen times while the engine idles. Watch the fluid reservoir to make sure it does not run out of fluid, or appear foamy. If foam does appear, shut off the engine and restart the bleeding process. 5. When fluid appears free of foam, top off the reservoir and check for leaks. This lengthy bleeding process will ensure the majority of the air is removed before initial startup to prevent pump damage and provide trouble-free steering. Steering Rack Specifications Rebuilt DSE Standard Width DSE Narrow Width Inner Ball Width Rack Travel (approx.) Turns lock-to-lock Tie Rod Thread Size 9/16-18 Input Shaft Spline ¾ -36 Fluid Flow Rate GPM 2.0GPM 2.0GPM Peak Pressure 1200PSI 1800PSI 1800PSI Pressure Fitting 9/16-18 Return Fitting 5/8-18

17 17 DSE/Mustang Rack Steering Stop Information Steering Limiter Maximum Size (in) Steering Angle* / / / ¼ / / / This guide is specific for a C6 suspension using the new steering arm, which is most likely to have wide tires and wheels installed. However, for Pro Spindle based suspensions, the results are similar. To install the limiter, roll the rubber boot away from the rack body and snap the plastic clip into place. *Note: This angle represents the outside wheel when in a turn. The forward edge of the inside wheel moves away from the frame and suspension, which negates any contact problem. When Ackerman is considered, the actual maximum steering angle is 33 degrees.

18 18 Steering Shaft Support Kit for Big Block Cars

19 19 Rear Coilover Installation

20 20 Rear Sway Bar Bushing Installation

21 21 Rear Sway Bar Installation

22 22 Front Sway Bar Installation

23 23 Steering Arm Installation ART MORRISON ENTERPRISES, INC (800) TH STREET EAST FIFE, WASHINGTON, (253) FAX (253)

24 24 Front Lower Control Arm Installation

25 25 Front Upper Control Arm Installation

26 26 Optional Equipment: Stainless Brake Line Kit

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34 34 Optional Equipment: Brake Proportioning Valve Mount Kit

35 35 Optional Equipment: Polyurethane LS Motor Mount Adapter Kit ART MORRISON ENTERPRISES, INC (800) TH STREET EAST FIFE, WASHINGTON, (253) FAX (253)

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37 37 Optional Equipment: Rubber LS Motor Mount Adapter Kit ART MORRISON ENTERPRISES, INC (800) TH STREET EAST FIFE, WASHINGTON, (253) FAX (253)

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39 39 Optional Equipment: Axle Housing Vent Kit

40 40 Fastener Information & Torque Specifications AME is now offering an upgraded line of fasteners to come standard with every AME chassis to provide you with OEM quality grade fasteners for your street machine or race car. AME s chassis fasteners utilize a Magni Coating for increased corrosion resistance, flanged nuts and bolts for a greater load distribution, and distorted thread locking nuts for a larger resistance to loosening forces. Advantages: Resists corrosion up to 13x s longer than typical Zinc plated fasteners Magni coating meets several OEM manufacturer specifications including GM, Ford, and Chrysler Flanged fasteners provide a larger load distribution on the mating surface typically eliminating washers Distorted thread lock nuts provide the increased resistance to loosing forces from vibration and movement Identification: Magni coated fasteners consist of a Zinc base coat with an Aluminum top coat which results in a gray-silver finish Distorted Thread locking nuts with flanges have a distinctive tapered top edge and the locking nuts without flanged contain a hexagon impression on the side. Instructions: All AME chassis are assembled with the Magni coated flanged bolts, but use Zinc plated jam nuts for ease of assembly and mock-up during the building process The matching lock nuts are provided loose in a bag with the chassis components Upon final assembly only replace the jam nuts with the Magni Distorted Thread Lock Nuts Installation of these nuts requires a significant increase in effort compared to other lock nuts. They will generate some amount of heat during installation due to the interference fit. Avoid reinstallation as much as possible. Like nylon-lock nuts, the locking capability wears slightly every use, therefore if the tightening effort dramatically decreases, replace the nut Reference AME torque specifications for final torque values Contact AME for any replacement pieces of hardware or to retro-fit your previously purchased chassis with the upgraded fasteners

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