C1/C4 Frame Installation Manual
CHASSISCONCEPTS
C1/C4 Assembly Manual
Step #1./ READ THIS ENTIRE MANUAL !
Step # 2./ READ THIS ENTIRE MANUAL !
Step # 3./ READ THIS ENTIRE MANUAL !
Step # 4./ READ THIS ENTIRE MANUAL !
Step # 5./ READ THIS ENTIRE MANUAL !
This will save you time, trouble and possibly unnecessary damage to your Corvette. Now that we have covered that, let’s begin
DON”T LOSE TRACK OF YOUR CORVETTE
You will need ; paper, pen or pencil, black marker, masking tape to mark items that are removed, containers, ZipLok bags and wire ties.
Just a bit of personal advice, take pictures of everything, before you start, and every step of the way. Before disassembling the Suspension – TAKE pictures. A digital camera or camcorder is great for this purpose. You can then put them on a computer and zoom in for a better look at how the parts are used. DO NOT trust your memory. Take pictures of the Suspension from every angle possible, and as close and detailed as possible. These photos will be a great help with the assembly of the new frame. With today’s digital technology, you can take 500 pictures and only keep what you want. MORE IS BETTER & SIZE DOES COUNT!!! Get close to what you are trying to remember, so that when you need it, it is just a click away.
Whenever possible, replace nuts, bolts, fasteners or straps back in the same place and direction that they came from. If this is not possible, then put them in ZipLok bags and mark what they are and the location that they came from and the picture #. Use a marker to draw a diagram on the bag.
CORVETTE – SAFETY FIRST
Disconnect all (Factory and Aftermarket) Cables and Wires from the Battery. Carefully remove the Battery from the Corvette. This will prevent accidental arcing while removing the Body.
TOOLS NEEDED FOR THE CORVETTE
Quality heavy duty hydraulic floor jack – 4 heavy duty jack stands
Body lifting device and straps – engine hoist – assorted hand tools
Body removal and installation
UNDER THE HOOD OF THE CORVETTE
Remove the hood from the Corvette by removing the 2 - 7/16” bolts from the top of the hood support bracket and let it rest on the inner fender. Remove the 3 – ˝”bolts on each side of the bottom of the hood, and leave the hinges attached to the inner fender. Replace the bolts in the hood for reinstallation when finished.
Remove the upper radiator hose and overflow hose from the radiator. Then remove the top radiator hold down bracket, fan and fan shroud. Then carefully remove the radiator.
On an after market air conditioned Corvette it will be necessary to break the lines at the back of the compressor, or to unbolt the compressor from the motor and secure it to the inner fender as a unit with the lines still attached.
Disconnect the wires from the Generator. Wire tie the wires to the inner fender, securely out of the way. Remove just the distributor shielding. Disconnect the wires going to the temperature sending unit, coil and choke. Feed them back towards the cowl and slip them under the wiper blade to keep them out of the way.
Wipe master cylinder and line(s) clean. Wrap a cloth around the
Wipe master cylinder and line(s) clean. Wrap a cloth around the line(s) about 6 inches below the fittings. Secure the cloth by wrapping tape around them. This will stop fluid from running down while the line(s) are disconnected. Disconnect the brake line(s) from the master cylinder. Cover the fitting(s) with a clean cloth. Wrap tape around the cloth to keep dirt out of the system. Gently move line(s) away from master cylinder to avoid catching them when body is raised.
Unbolt and remove the Pitman Arm from the bottom of the Steering Column. Unbolt Steering Box from the Chassis. Remove wiring from the Column. Remove Steering Wheel and Collar, so that the Column can be removed from the Body after it has been lifted off the Chassis.
Remove the clutch return spring attached to the column mounting plate on the cowl.
On a standard shift Corvette, the “Z” bar assembly is attached to the frame just behind the steering column. Remove the spring clip from the bottom of the clutch rod, and then completely remove the adjustment assembly from the clutch rod and remove the “Z” bar assembly.
Remove the tach drive cable from the back of the Generator.
Disconnect the oil line from the fitting on the back of the motor with a 7/16” open end, and a 5/16” line wrench and carefully tie it back to the cowl. It is located behind the distributor, just before the bellhousing.
Remove the spring from the throttle rod at the carbureator, and the cotter pin from the accelerator lever, to remove the throttle rod. Wire tie the accelerator lever back to the cowl. Remove the hexhead bolt that holds the braided ground wire from the accelerator lever.
ON THE INSIDE OF THE CORVETTE
On a standard shift Corvette, remove the Console Plate, Shifter Boot, shift ball and T handle.
Remove the Instrument Cluster and Trim to gain better access to the Steering Column.
UNDER THE CORVETTE
Jack the Corvette up to a comfortable height and secure it on a good set of jack stands that are capable of handling the weight and will not slip.
THE REAR OF THE CORVETTE
Remove the exhaust from under the rear of the car. While there, remove any ground straps or wires attached to the frame. Pull them back through the frame until they hang free from the body. If the Corvette is equipped with a radio, disconnect the antenna ground from the frame, remove the rear bumpers and ALL of the bumper brackets, making sure that you keep any shims with the bracket it was with.
THE FRONT OF THE CORVETTE
Remove the front bumpers, grille and ALL of the bumper brackets, again keeping any shims with the proper brackets. While there, remove the radiator support bolts, drain the radiator and remove the lower radiator hose from the radiator. Both the upper and lower radiator hose can remain attached to the motor.
THE SIDES OF THE CORVETTE
Remove ALL Body Mount Bolts
ON THE UNDERSIDE OF THE CORVETTE
Remove any splash pans that are attached to the bottom of the drivers and passengers floor and.
Disconnect the speedometer cable so that it hangs free. Disconnect the plug to the backup switch, if so equipped. On an automatic Corvette, disconnect the shifter rod from the trans, neutral safety switch and the hoses from the trans cooler, if equipped.
Drain Fuel Tank and remove Hose from Fuel Line on the Chassis.
Remove the wire harness with three connections (1/4, 5/16 and 9/16) from the starter motor at the solenoid. Reattach the 9/16, 1/4 and 5/16 nuts. Feed the harness back to the body and secure it with a wire tie.
Remove the emergency cable from the adjuster sleeve and make sure that it is not attached to the frame and that it hangs free from the body.
Remove the seatbelt supports, if equipped.
CORVETTE BODY LIFT
A Corvette convertible requires 6 lift points, the very rear of each rocker panel, right at the front cowl body mount and the engine lift at the radiator support. The 4 lift points on the main body should all wind up at a central lift point in the center of the roof. The engine lift will be used to lift the front, and to balance the load. Professional body straps should be used that have at least a 2” wide reverse lift point. The cradle should be attached to the engine lift with a chain bolted to the upper radiator hold down holes. The Body also requires a support for the rear so that the door jams are not broken. The best way to do this is with door jam supports that bolt to the door hinges and the top support brackets. This can also be done by attaching 2 more straps to the central lift point, and running them back under each set of taillights. Pressure must constantly be kept on these straps to avoid damage.
Attach the 6 Lift Straps to a lifting device located at a point (as shown in Diagram #?? above the center of the Roof. Attach a Motor Lift (Cherry Picker) to the top as shown in Diagram #?? of the Radiator Support, through the holes that hold the top shroud Bracket.
Start lifting the Body equally from all points. If the Body does not start to separate from the frame, or is hung up at one spot, as you begin to take weight off of it - STOP - check to see if anything was forgotten and is still connected. If the Body begins to separate from the frame, raise the rear of the Body a little more than the front. While doing this, check that the bottom of the rear fenders and the rear body panel is clearing the frame. Also check the Fuel Line is free as you lift the body. As you lift the Body higher, increase the angle until the front of the car is approx. 5 inches lower than the rear. It may be necessary to slide the body slightly forward to allow the Radiator Support to clear the frame. As you continue to lift, level the body and keep checking for things that can get caught or trapped. This would include; Radiator Support, engine compartment wiring, Brake Lines, Speedometer Cable, Shifter, E-Brake Cable, Fuel Line, antenna ground wire and Seat Belt anchors. Continue lifting until the Body is high enough to roll the Chassis out from the rear of the car.
As soon as the Frame is clear, document the Body Cushion and Shim Locations – Be very careful to note and document the number of Shims at each Body mount position. Remove and store them individually, mark the Body Mount position on a Zip-Lok Bag, and keep them separated as #1R, #1L, #2R, #2L, #3R, #3L, etc.
Documentation at this point will make the Body alignment much easier when re-installing the Body.
Chassis Preparation – Original
Refurbish Original Style Chassis as desired.
Position the Body Mount Cushion, with the original number of Shims on each Cushion that were present when the Body was removed. Secure them with Masking Tape at each Body Mount Location.
Re-install the Original Chassis by following the instructions in the Remounting Body Section of this Manual.
Chassis Assembly and Preparation
CHASSIS CONCEPTS – C1/C4 Replacement Chassis
ALL CHASSIS ARE SHIPPED DRY
PLEASE GREASE ALL FITTINGS AND LUBRICATION POINTS
DIFFERENTIAL HAS POSI FLUID – CHECK BEFORE USE
Acquire complete Front and Rear Suspension from a 1989 thru 1996 Corvette with the Rack and Pinion. Make sure to get the Strap that secures the Steering Rack to the “K” Member.
Be sure that ALL NUTS, BOLTS, WASHERS AND HARDWARE are included. This will make the installation safer and easier if the correct parts are used.
Clean, Media Blast and Clear Coat all of the “Factory” Nuts, Bolts, Washers and loose parts.
Prepare the Suspension Parts, to your specifications (New, Refurbished or Cleaned), for installation.
Due to varying tolerances in the Suspension Parts and replacement bushings, adjustments may be necessary. Check for clearance for installation of Suspension Parts as shown in Diagram # ?? . Adjust opening as required, as shown in Diagram # ??.
Differential Bushings
Strut Bushing
Dogbones
Rack Mount Bracket
FRONT SUSPENSION
Install Left Lower Control Arm using ?? Nuts and Bolts.
Install Upper Control Arms using ?? Fitted Bolts and ?? Lock Nuts.
If desired, shorten Upper Control Arm Bolts for Appearance, as shown in Diagram # ??.
Install Front Spring using four ?? Bolts and ?? Nuts, as per Diagram #??.
Attach Spindle Assembly to Lower Ball Joint, tighten and install Cotter Pin.
Place Floor Jack under Lower Ball Joint(remove Grease Fitting) and raise the Jack as shown in Diagram #??. Guide Spindle Assembly into Upper Ball Joint, tighten and install Cotter Pin. If you have a heavy Spring, it may require weight on the frame, as shown in Diagram #??.
Lower Jack and insert extended Shock into place. Tighten top mount of Shock into Chassis. Raise Jack to position lower mount of the Shock and install ?? Bolts and ?? Lock Nuts.
Repeat procedure to the Right side.
Install Rack and Pinion with one ?? Bolt, Flat Washer and ?? Nut along with the O.E.M. Strap using two ?? Nuts, Flat Washers, Lock Washers and ?? Nuts.
Install Front Tie Bar to L&R Control Arm Towers using 12 point Bolts provided
REAR SUSPENSION
Install the Rear Differential Housing with two ?? Bolts, Flat Washers and ?? Lock Nuts. The Differential Bushings Bolts are installed front to rear for clearance. They will also need to be trimmed by ?? inches to a 4 ˝ Bolt, as shown in Diagram # ??. Use Thin Lock Nut that is supplied, or use enclosed bolt kit as shown.
Loosely install Torque Bar Assembly to the Pinion Housing with ?? Bolts, Flat Washer and ?? Lock Nuts and to the Chassis with ?? Bolt, Flat Washers and ?? Lock Nut as shown in Diagram #??.
Adjust Pinion Angle to 2-5 degrees using adjustable Torque Arm Assembly, and tighten all bolts.
LEFT REAR
Install DogBones to Chassis first, being careful not to cross thread the bolts.
Install Short Upper DogBone with ?? Bolts with the ?? Nut to the outside.
Install Long Lower DogBone with the ?? Bolts into the Threaded Chassis Mounting Boss with caution. Be certain that it is aligned properly. If it is not, it can cross thread and cause damage.
Assemble Rear Spindle Housing as shown in Diagram #??.
Install Rear Spindle Housing to the DogBones using ?? Bolts, Squared Washers and ?? Lock Nuts.
Install Half Shaft to Differential with ?? Bolts and Flat Plates.
Install Lower Strut Bars into Spindle Housing using ?? Bolts and ?? Nuts as shown in Diagram # ??. Swing the other end of the Strut Bar up to Differential Housing Bracket, and install with the Eliptical Bolts, Set Washers and ?? Lock Nuts as shown in Diagram # ??.
RIGHT REAR
Repeat procedure same as Left Rear.
Shorten Toe Bar Assembly ˝ inch per side and install to rear of the Differential wit three ?? Bolts.
Install Rear Spring, with the same amount of Spacers as when removed, with O.E.M. Brackets and ?? Bolts.
Place Floor Jack under Rear Spring next to Bushing Hole and raise up until ?? Nut can be threaded onto ?? Spring Bolt.
Install Rear Shocks.
DRIVELINE INSTALLATION
Install desired Driveline completely, including all components, Adapters and Brackets. It is much easier to do this with the body off, while you have access to the open chassis. These Items would include; Motor, all Motor Accessories (Pumps, Pulleys, Belts, A/C, etc.) Trans, Driveshaft, Clutch Z bar and Linkage, Shifter, Battery and shield, Exhaust System, P/S Hoses and Trans Fluid Lines.
If standard trans, fill with gear lube.
Fill rear differential with GM Positraction Fluid and Additive only.
Install Steering Linkage Adapters to the Chassis. Start with a ?? X DD Swivel. Attach the ?? end to the C4 Rack. Next, Slip one end of the DD Bar into the DD end. If neccasary, slide the Heim Joint on to the DD Bar and mount the Heim Joint Adapter to the back of the Drivers Upper Control Arm Tower, as shown in Diagram #??. Now install the Steering Column Adapter X DD Swivel to the top end of the DD Bar. Adjust Assembly for proper clearance and tighten all Nuts and Allen Bolts. You will complete the rest of this procedure after the Body is in place.
Install E-Brake Kit. Determine the type of Kit required and the location of the Hand Brake. Install Kit as per Manufacturers Directions (see Digram # ?? for suggestions).
Install and hook up all Fuel Lines.
Install Brake Lines and Adapters for Dual Master Cylinder.
Install applicable bumper brackets.
Position the Body Mount Cushions (Polyurathane is suggested) in the proper locations as shown in Diagram # ??. You will reinstall the Shims, as the Body is lowered.
CHECK EVERY NUT, BOLT, SCREW, BRACKET AND STRAP THAT YOU CAN SEE – YOU CAN NEVER BE TOO SAFE !!!!!
You are now ready to re-install the Body onto your New CHASSIS CONCEPTS C1/C4 Chassis.
This is basically a reverse of what you have done so far.
CHECK FOR CLEARANCE EVERY STEP OF THE WAY !!!!!
Roll the Chassis back under the Body. Slowly lower the body down level until it is about a foot from the Frame. Lower the front approx. 5 inches, and keep it slightly forward until the radiator support is 1 inch from the point that it mounts to the frame.
At this point you must determine what Body Modifications will be required. Even though The Chassis Concepts C1/C4 Chassis is designed to be generally universal, there still may be unique circumstances with you application that may result in further modifications to the Body, or fabrications to the Chassis.
1/ Two notches are required to the Inner Fender on each side to clear the Upper Control Arm as shown in Diagram #??.
2/ The Spare Tire Well must be cut in two places and turned upside down to be glassed in, as shown in Diagram # ??.
3/ Some applications require a notch in the Rear Inner Fender to clear the DogBone Support.
4/ Early C1 Corvettes may require repositioning of the Main Body Mount Holes.
5/ 53-57 Corvettes will require the removal of the Front Bumper Brackets.
After these modifications are made, you are ready to proceed.
You must Re-check the following items as the Body nears their locations, to make sure that they are going in place; Body Modification Clearance, Shifter, Speedometer Cable, E-Brake Cable, Seat Belt Anchors, gas tank wires and antenna ground. Begin to lower the rear and level the Body, while moving the Body to the rear to line up the mounts, until it rests properly on the front two radiator support mounting holes.
Do not continue to the next step unless the weight is off of the lifting devices, and the Body is resting squarely on ALL of the main Body mounts. The front radiator support mounts and the rear Body mounts should not be touching (putting weight on) the Chassis. These mounts will be tightened after the Center Body mounts are secure. The priority now is to get a solid and level mount of the main Body. The rear, mount will be dealt with, once the main Body is secure.
Inspect the Body mount cushions and shims. Do they feel tight? Can you move them or twist them around? If the answer is yes, you will have to reposition the shims. The Body should sit flat and even on these mounting positions. If your doors were aligned properly prior to removing the Body, they should have the same fit and open and close correctly. If they do not, you must correct this problem before going any further. Check your main Body shims and make sure that the Radiator Support and Rear Body mount are not interfering. It is now time to shim the Rear Body mount. The purpose of this procedure is only to take up the space between the mount and the Body, not to lift or lower the position. It is OK to raise the Body off the mount in order to insert the shim, but the shim should only be a spacer – not a wedge. Now you will do the same with the Radiator Support. Remember that this mount controls the up and down, as well as the left to right height of the front end. A good rule of thumb is to put enough shims in place for zero pressure on the frame, and then add one more shim to each side of the radiator support mount. Any opposite pressure can cause the fiberglass to fatigue and crack. Insert all of the Body bolts, washers and cushions in the Radiator Support and Body mounts. Gently tighten the main body mounts a little at a time in a criss cross manner. When tight, the doors should open and close properly. Tighten the Rear Body mounts and the Radiator Support, and once again check the doors. This adjustment will also affect the way that the doors will operate.
UNDER THE REAR OF THE CORVETTE
Hook up the Fuel Tank.
Hook up the antenna wires and ground
Install the rear Bumper Brackets and bumpers. Replace the gas tank overflow.
Install the exhaust tips (if under car exhaust) and license plate trim.
UNDER THE CORVETTE
Re-install splash pans.
Re-attach Starter wires
Re-install speedometer cable
Re-attach neutral safety switch and transmission linkage and cooler lines, if the Corvette is an automatic.
Re-attach back up light switch, if so equipped.
Attach E-Brake cable.
UNDER FRONT OF THE CORVETTE
Install bumper brackets.
Re-install front grille.
Install front bumpers and license plate bar
ON THE INSIDE OF THE CORVETTE
Re-install steering column. With the CHASSIS CONCEPTS C1/C4 Chassis, we recommend a Flaming Rivers, tilt, Corvette direct replacement column (information is in the resource guide). Place the lower portion of the column through the firewall. Install as per Manufacturers Instructions. Attach the 9/16 X DD swivel joint to the end of the shaft, attaching the 9/16 end. Loosely install the column. Measure and cut the DD bar to the desired length. Be very careful, not to cut it short (like the guy who said, “I cut it 3 times, and it is still too short”). Remember that the DD bar must fit inside the end of each swivel. Notch the cut end of the DD bar to match the uncut end. This is necessary to allow the allen bolt to secure the swivel. Secure the steering column and all joints.
Re-Install Instrument Cluster and all associated pieces.
Re-install shifter boot, console plate, T handle and shifter ball.
UNDER THE HOOD OF THE CORVETTE
Re-install the radiator, hoses, fan and shroud.
Hook up A/C, if so equipped.
Attach engine harnesses, as removed. Crate motors and transmissions may require special computers, switches, throttle control and wiring. Check with the supplier for those instructions.
Re-install oil gauge line.
Attach tach drive cable.
Attach throttle rod and spring.
Attach clutch linkage and return spring.
Install brake adapter lines from the new proportioning valve to the master cylinder (must be a dual line unit, 67 up).
Reinstall hood and hood prop.
BATTERY CABLES – The very last thing to be hooked up. Make sure that everything is off – key, lights, etc. Connect negative cable, and all additional ground wires. Touch the positive cable to the terminal, and check for spark. If everything is off, there should be no spark. If there is a constant spark, you need to check that everything is off, and that no wires were pinched or cut as the Body was being lowered. If no spark is present, connect the positive cable and check all of the electrical operations of the Corvette. DO NOT start the motor until the service procedure has been performed.
SERVICE PROCEDURE FOR THE NEW CORVETTE CHASSIS
Fill master cylinder and bleed brakes.
Fill and check all engine fluids – oil, antifrezze, automatic trans fluid and brake fluid. Start motor and check for leaks. Allow engine to reach operating temperature. Shut down and check again for leaks.
Charge A/C if so equipped.
Align front and rear suspension.
TAKE FOR A TEST RIDE AND ENJOY
CHASSISCONCEPTS
C1/C4 Assembly Manual
Step #1./ READ THIS ENTIRE MANUAL !
Step # 2./ READ THIS ENTIRE MANUAL !
Step # 3./ READ THIS ENTIRE MANUAL !
Step # 4./ READ THIS ENTIRE MANUAL !
Step # 5./ READ THIS ENTIRE MANUAL !
This will save you time, trouble and possibly unnecessary damage to your Corvette. Now that we have covered that, let’s begin
DON”T LOSE TRACK OF YOUR CORVETTE
You will need ; paper, pen or pencil, black marker, masking tape to mark items that are removed, containers, ZipLok bags and wire ties.
Just a bit of personal advice, take pictures of everything, before you start, and every step of the way. Before disassembling the Suspension – TAKE pictures. A digital camera or camcorder is great for this purpose. You can then put them on a computer and zoom in for a better look at how the parts are used. DO NOT trust your memory. Take pictures of the Suspension from every angle possible, and as close and detailed as possible. These photos will be a great help with the assembly of the new frame. With today’s digital technology, you can take 500 pictures and only keep what you want. MORE IS BETTER & SIZE DOES COUNT!!! Get close to what you are trying to remember, so that when you need it, it is just a click away.
Whenever possible, replace nuts, bolts, fasteners or straps back in the same place and direction that they came from. If this is not possible, then put them in ZipLok bags and mark what they are and the location that they came from and the picture #. Use a marker to draw a diagram on the bag.
CORVETTE – SAFETY FIRST
Disconnect all (Factory and Aftermarket) Cables and Wires from the Battery. Carefully remove the Battery from the Corvette. This will prevent accidental arcing while removing the Body.
TOOLS NEEDED FOR THE CORVETTE
Quality heavy duty hydraulic floor jack – 4 heavy duty jack stands Body lifting device and straps – engine hoist – assorted hand tools
Body removal and installation
UNDER THE HOOD OF THE CORVETTE
Remove the hood from the Corvette by removing the 2 - 7/16” bolts from the top of the hood support bracket and let it rest on the inner fender. Remove the 3 – ˝”bolts on each side of the bottom of the hood, and leave the hinges attached to the inner fender. Replace the bolts in the hood for reinstallation when finished.
Remove the upper radiator hose and overflow hose from the radiator. Then remove the top radiator hold down bracket, fan and fan shroud. Then carefully remove the radiator.
On an after market air conditioned Corvette it will be necessary to break the lines at the back of the compressor, or to unbolt the compressor from the motor and secure it to the inner fender as a unit with the lines still attached.
Disconnect the wires from the Generator. Wire tie the wires to the inner fender, securely out of the way. Remove just the distributor shielding. Disconnect the wires going to the temperature sending unit, coil and choke. Feed them back towards the cowl and slip them under the wiper blade to keep them out of the way.
Wipe master cylinder and line(s) clean. Wrap a cloth around the
Wipe master cylinder and line(s) clean. Wrap a cloth around the line(s) about 6 inches below the fittings. Secure the cloth by wrapping tape around them. This will stop fluid from running down while the line(s) are disconnected. Disconnect the brake line(s) from the master cylinder. Cover the fitting(s) with a clean cloth. Wrap tape around the cloth to keep dirt out of the system. Gently move line(s) away from master cylinder to avoid catching them when body is raised.
Unbolt and remove the Pitman Arm from the bottom of the Steering Column. Unbolt Steering Box from the Chassis. Remove wiring from the Column. Remove Steering Wheel and Collar, so that the Column can be removed from the Body after it has been lifted off the Chassis.
Remove the clutch return spring attached to the column mounting plate on the cowl.
On a standard shift Corvette, the “Z” bar assembly is attached to the frame just behind the steering column. Remove the spring clip from the bottom of the clutch rod, and then completely remove the adjustment assembly from the clutch rod and remove the “Z” bar assembly.
Remove the tach drive cable from the back of the Generator.
Disconnect the oil line from the fitting on the back of the motor with a 7/16” open end, and a 5/16” line wrench and carefully tie it back to the cowl. It is located behind the distributor, just before the bellhousing.
Remove the spring from the throttle rod at the carbureator, and the cotter pin from the accelerator lever, to remove the throttle rod. Wire tie the accelerator lever back to the cowl. Remove the hexhead bolt that holds the braided ground wire from the accelerator lever.
ON THE INSIDE OF THE CORVETTE
On a standard shift Corvette, remove the Console Plate, Shifter Boot, shift ball and T handle.
Remove the Instrument Cluster and Trim to gain better access to the Steering Column.
UNDER THE CORVETTE
Jack the Corvette up to a comfortable height and secure it on a good set of jack stands that are capable of handling the weight and will not slip.
THE REAR OF THE CORVETTE
Remove the exhaust from under the rear of the car. While there, remove any ground straps or wires attached to the frame. Pull them back through the frame until they hang free from the body. If the Corvette is equipped with a radio, disconnect the antenna ground from the frame, remove the rear bumpers and ALL of the bumper brackets, making sure that you keep any shims with the bracket it was with.
THE FRONT OF THE CORVETTE
Remove the front bumpers, grille and ALL of the bumper brackets, again keeping any shims with the proper brackets. While there, remove the radiator support bolts, drain the radiator and remove the lower radiator hose from the radiator. Both the upper and lower radiator hose can remain attached to the motor.
THE SIDES OF THE CORVETTE Remove ALL Body Mount Bolts
ON THE UNDERSIDE OF THE CORVETTE
Remove any splash pans that are attached to the bottom of the drivers and passengers floor and.
Disconnect the speedometer cable so that it hangs free. Disconnect the plug to the backup switch, if so equipped. On an automatic Corvette, disconnect the shifter rod from the trans, neutral safety switch and the hoses from the trans cooler, if equipped.
Drain Fuel Tank and remove Hose from Fuel Line on the Chassis.
Remove the wire harness with three connections (1/4, 5/16 and 9/16) from the starter motor at the solenoid. Reattach the 9/16, 1/4 and 5/16 nuts. Feed the harness back to the body and secure it with a wire tie.
Remove the emergency cable from the adjuster sleeve and make sure that it is not attached to the frame and that it hangs free from the body.
Remove the seatbelt supports, if equipped.
CORVETTE BODY LIFT
A Corvette convertible requires 6 lift points, the very rear of each rocker panel, right at the front cowl body mount and the engine lift at the radiator support. The 4 lift points on the main body should all wind up at a central lift point in the center of the roof. The engine lift will be used to lift the front, and to balance the load. Professional body straps should be used that have at least a 2” wide reverse lift point. The cradle should be attached to the engine lift with a chain bolted to the upper radiator hold down holes. The Body also requires a support for the rear so that the door jams are not broken. The best way to do this is with door jam supports that bolt to the door hinges and the top support brackets. This can also be done by attaching 2 more straps to the central lift point, and running them back under each set of taillights. Pressure must constantly be kept on these straps to avoid damage.
Attach the 6 Lift Straps to a lifting device located at a point (as shown in Diagram #?? above the center of the Roof. Attach a Motor Lift (Cherry Picker) to the top as shown in Diagram #?? of the Radiator Support, through the holes that hold the top shroud Bracket.
Start lifting the Body equally from all points. If the Body does not start to separate from the frame, or is hung up at one spot, as you begin to take weight off of it - STOP - check to see if anything was forgotten and is still connected. If the Body begins to separate from the frame, raise the rear of the Body a little more than the front. While doing this, check that the bottom of the rear fenders and the rear body panel is clearing the frame. Also check the Fuel Line is free as you lift the body. As you lift the Body higher, increase the angle until the front of the car is approx. 5 inches lower than the rear. It may be necessary to slide the body slightly forward to allow the Radiator Support to clear the frame. As you continue to lift, level the body and keep checking for things that can get caught or trapped. This would include; Radiator Support, engine compartment wiring, Brake Lines, Speedometer Cable, Shifter, E-Brake Cable, Fuel Line, antenna ground wire and Seat Belt anchors. Continue lifting until the Body is high enough to roll the Chassis out from the rear of the car.
As soon as the Frame is clear, document the Body Cushion and Shim Locations – Be very careful to note and document the number of Shims at each Body mount position. Remove and store them individually, mark the Body Mount position on a Zip-Lok Bag, and keep them separated as #1R, #1L, #2R, #2L, #3R, #3L, etc.
Documentation at this point will make the Body alignment much easier when re-installing the Body.
Chassis Preparation – Original
Refurbish Original Style Chassis as desired.
Position the Body Mount Cushion, with the original number of Shims on each Cushion that were present when the Body was removed. Secure them with Masking Tape at each Body Mount Location.
Re-install the Original Chassis by following the instructions in the Remounting Body Section of this Manual.
Chassis Assembly and Preparation
CHASSIS CONCEPTS – C1/C4 Replacement Chassis
ALL CHASSIS ARE SHIPPED DRY
PLEASE GREASE ALL FITTINGS AND LUBRICATION POINTS
DIFFERENTIAL HAS POSI FLUID – CHECK BEFORE USE
Acquire complete Front and Rear Suspension from a 1989 thru 1996 Corvette with the Rack and Pinion. Make sure to get the Strap that secures the Steering Rack to the “K” Member.
Be sure that ALL NUTS, BOLTS, WASHERS AND HARDWARE are included. This will make the installation safer and easier if the correct parts are used.
Clean, Media Blast and Clear Coat all of the “Factory” Nuts, Bolts, Washers and loose parts.
Prepare the Suspension Parts, to your specifications (New, Refurbished or Cleaned), for installation.
Due to varying tolerances in the Suspension Parts and replacement bushings, adjustments may be necessary. Check for clearance for installation of Suspension Parts as shown in Diagram # ?? . Adjust opening as required, as shown in Diagram # ??.
Differential Bushings
Strut Bushing
Dogbones
Rack Mount Bracket
FRONT SUSPENSION
Install Left Lower Control Arm using ?? Nuts and Bolts.
Install Upper Control Arms using ?? Fitted Bolts and ?? Lock Nuts.
If desired, shorten Upper Control Arm Bolts for Appearance, as shown in Diagram # ??.
Install Front Spring using four ?? Bolts and ?? Nuts, as per Diagram #??.
Attach Spindle Assembly to Lower Ball Joint, tighten and install Cotter Pin.
Place Floor Jack under Lower Ball Joint(remove Grease Fitting) and raise the Jack as shown in Diagram #??. Guide Spindle Assembly into Upper Ball Joint, tighten and install Cotter Pin. If you have a heavy Spring, it may require weight on the frame, as shown in Diagram #??.
Lower Jack and insert extended Shock into place. Tighten top mount of Shock into Chassis. Raise Jack to position lower mount of the Shock and install ?? Bolts and ?? Lock Nuts.
Repeat procedure to the Right side.
Install Rack and Pinion with one ?? Bolt, Flat Washer and ?? Nut along with the O.E.M. Strap using two ?? Nuts, Flat Washers, Lock Washers and ?? Nuts.
Install Front Tie Bar to L&R Control Arm Towers using 12 point Bolts provided
REAR SUSPENSION
Install the Rear Differential Housing with two ?? Bolts, Flat Washers and ?? Lock Nuts. The Differential Bushings Bolts are installed front to rear for clearance. They will also need to be trimmed by ?? inches to a 4 ˝ Bolt, as shown in Diagram # ??. Use Thin Lock Nut that is supplied, or use enclosed bolt kit as shown.
Loosely install Torque Bar Assembly to the Pinion Housing with ?? Bolts, Flat Washer and ?? Lock Nuts and to the Chassis with ?? Bolt, Flat Washers and ?? Lock Nut as shown in Diagram #??.
Adjust Pinion Angle to 2-5 degrees using adjustable Torque Arm Assembly, and tighten all bolts.
LEFT REAR
Install DogBones to Chassis first, being careful not to cross thread the bolts.
Install Short Upper DogBone with ?? Bolts with the ?? Nut to the outside.
Install Long Lower DogBone with the ?? Bolts into the Threaded Chassis Mounting Boss with caution. Be certain that it is aligned properly. If it is not, it can cross thread and cause damage.
Assemble Rear Spindle Housing as shown in Diagram #??.
Install Rear Spindle Housing to the DogBones using ?? Bolts, Squared Washers and ?? Lock Nuts.
Install Half Shaft to Differential with ?? Bolts and Flat Plates.
Install Lower Strut Bars into Spindle Housing using ?? Bolts and ?? Nuts as shown in Diagram # ??. Swing the other end of the Strut Bar up to Differential Housing Bracket, and install with the Eliptical Bolts, Set Washers and ?? Lock Nuts as shown in Diagram # ??.
RIGHT REAR
Repeat procedure same as Left Rear.
Shorten Toe Bar Assembly ˝ inch per side and install to rear of the Differential wit three ?? Bolts.
Install Rear Spring, with the same amount of Spacers as when removed, with O.E.M. Brackets and ?? Bolts.
Place Floor Jack under Rear Spring next to Bushing Hole and raise up until ?? Nut can be threaded onto ?? Spring Bolt.
Install Rear Shocks.
DRIVELINE INSTALLATION
Install desired Driveline completely, including all components, Adapters and Brackets. It is much easier to do this with the body off, while you have access to the open chassis. These Items would include; Motor, all Motor Accessories (Pumps, Pulleys, Belts, A/C, etc.) Trans, Driveshaft, Clutch Z bar and Linkage, Shifter, Battery and shield, Exhaust System, P/S Hoses and Trans Fluid Lines.
If standard trans, fill with gear lube.
Fill rear differential with GM Positraction Fluid and Additive only.
Install Steering Linkage Adapters to the Chassis. Start with a ?? X DD Swivel. Attach the ?? end to the C4 Rack. Next, Slip one end of the DD Bar into the DD end. If neccasary, slide the Heim Joint on to the DD Bar and mount the Heim Joint Adapter to the back of the Drivers Upper Control Arm Tower, as shown in Diagram #??. Now install the Steering Column Adapter X DD Swivel to the top end of the DD Bar. Adjust Assembly for proper clearance and tighten all Nuts and Allen Bolts. You will complete the rest of this procedure after the Body is in place.
Install E-Brake Kit. Determine the type of Kit required and the location of the Hand Brake. Install Kit as per Manufacturers Directions (see Digram # ?? for suggestions).
Install and hook up all Fuel Lines.
Install Brake Lines and Adapters for Dual Master Cylinder.
Install applicable bumper brackets.
Position the Body Mount Cushions (Polyurathane is suggested) in the proper locations as shown in Diagram # ??. You will reinstall the Shims, as the Body is lowered.
CHECK EVERY NUT, BOLT, SCREW, BRACKET AND STRAP THAT YOU CAN SEE – YOU CAN NEVER BE TOO SAFE !!!!!
You are now ready to re-install the Body onto your New CHASSIS CONCEPTS C1/C4 Chassis.
This is basically a reverse of what you have done so far.
CHECK FOR CLEARANCE EVERY STEP OF THE WAY !!!!!
Roll the Chassis back under the Body. Slowly lower the body down level until it is about a foot from the Frame. Lower the front approx. 5 inches, and keep it slightly forward until the radiator support is 1 inch from the point that it mounts to the frame.
At this point you must determine what Body Modifications will be required. Even though The Chassis Concepts C1/C4 Chassis is designed to be generally universal, there still may be unique circumstances with you application that may result in further modifications to the Body, or fabrications to the Chassis.
1/ Two notches are required to the Inner Fender on each side to clear the Upper Control Arm as shown in Diagram #??.
2/ The Spare Tire Well must be cut in two places and turned upside down to be glassed in, as shown in Diagram # ??.
3/ Some applications require a notch in the Rear Inner Fender to clear the DogBone Support.
4/ Early C1 Corvettes may require repositioning of the Main Body Mount Holes.
5/ 53-57 Corvettes will require the removal of the Front Bumper Brackets.
After these modifications are made, you are ready to proceed.
You must Re-check the following items as the Body nears their locations, to make sure that they are going in place; Body Modification Clearance, Shifter, Speedometer Cable, E-Brake Cable, Seat Belt Anchors, gas tank wires and antenna ground. Begin to lower the rear and level the Body, while moving the Body to the rear to line up the mounts, until it rests properly on the front two radiator support mounting holes.
Do not continue to the next step unless the weight is off of the lifting devices, and the Body is resting squarely on ALL of the main Body mounts. The front radiator support mounts and the rear Body mounts should not be touching (putting weight on) the Chassis. These mounts will be tightened after the Center Body mounts are secure. The priority now is to get a solid and level mount of the main Body. The rear, mount will be dealt with, once the main Body is secure.
Inspect the Body mount cushions and shims. Do they feel tight? Can you move them or twist them around? If the answer is yes, you will have to reposition the shims. The Body should sit flat and even on these mounting positions. If your doors were aligned properly prior to removing the Body, they should have the same fit and open and close correctly. If they do not, you must correct this problem before going any further. Check your main Body shims and make sure that the Radiator Support and Rear Body mount are not interfering. It is now time to shim the Rear Body mount. The purpose of this procedure is only to take up the space between the mount and the Body, not to lift or lower the position. It is OK to raise the Body off the mount in order to insert the shim, but the shim should only be a spacer – not a wedge. Now you will do the same with the Radiator Support. Remember that this mount controls the up and down, as well as the left to right height of the front end. A good rule of thumb is to put enough shims in place for zero pressure on the frame, and then add one more shim to each side of the radiator support mount. Any opposite pressure can cause the fiberglass to fatigue and crack. Insert all of the Body bolts, washers and cushions in the Radiator Support and Body mounts. Gently tighten the main body mounts a little at a time in a criss cross manner. When tight, the doors should open and close properly. Tighten the Rear Body mounts and the Radiator Support, and once again check the doors. This adjustment will also affect the way that the doors will operate.
UNDER THE REAR OF THE CORVETTE
Hook up the Fuel Tank.
Hook up the antenna wires and ground
Install the rear Bumper Brackets and bumpers. Replace the gas tank overflow.
Install the exhaust tips (if under car exhaust) and license plate trim.
UNDER THE CORVETTE
Re-install splash pans.
Re-attach Starter wires
Re-install speedometer cable
Re-attach neutral safety switch and transmission linkage and cooler lines, if the Corvette is an automatic.
Re-attach back up light switch, if so equipped.
Attach E-Brake cable.
UNDER FRONT OF THE CORVETTE
Install bumper brackets.
Re-install front grille.
Install front bumpers and license plate bar
ON THE INSIDE OF THE CORVETTE
Re-install steering column. With the CHASSIS CONCEPTS C1/C4 Chassis, we recommend a Flaming Rivers, tilt, Corvette direct replacement column (information is in the resource guide). Place the lower portion of the column through the firewall. Install as per Manufacturers Instructions. Attach the 9/16 X DD swivel joint to the end of the shaft, attaching the 9/16 end. Loosely install the column. Measure and cut the DD bar to the desired length. Be very careful, not to cut it short (like the guy who said, “I cut it 3 times, and it is still too short”). Remember that the DD bar must fit inside the end of each swivel. Notch the cut end of the DD bar to match the uncut end. This is necessary to allow the allen bolt to secure the swivel. Secure the steering column and all joints.
Re-Install Instrument Cluster and all associated pieces.
Re-install shifter boot, console plate, T handle and shifter ball.
UNDER THE HOOD OF THE CORVETTE
Re-install the radiator, hoses, fan and shroud.
Hook up A/C, if so equipped.
Attach engine harnesses, as removed. Crate motors and transmissions may require special computers, switches, throttle control and wiring. Check with the supplier for those instructions.
Re-install oil gauge line.
Attach tach drive cable.
Attach throttle rod and spring.
Attach clutch linkage and return spring.
Install brake adapter lines from the new proportioning valve to the master cylinder (must be a dual line unit, 67 up).
Reinstall hood and hood prop.
BATTERY CABLES – The very last thing to be hooked up. Make sure that everything is off – key, lights, etc. Connect negative cable, and all additional ground wires. Touch the positive cable to the terminal, and check for spark. If everything is off, there should be no spark. If there is a constant spark, you need to check that everything is off, and that no wires were pinched or cut as the Body was being lowered. If no spark is present, connect the positive cable and check all of the electrical operations of the Corvette. DO NOT start the motor until the service procedure has been performed.
SERVICE PROCEDURE FOR THE NEW CORVETTE CHASSIS
Fill master cylinder and bleed brakes.
Fill and check all engine fluids – oil, antifrezze, automatic trans fluid and brake fluid. Start motor and check for leaks. Allow engine to reach operating temperature. Shut down and check again for leaks.
Charge A/C if so equipped.
Align front and rear suspension.
TAKE FOR A TEST RIDE AND ENJOY