Edelbrock 6876 User manual

TUBULAR EXHAUST SYSTEM
CATALOG #6876/7976
1989-1992 Camaro & Firebird 305 &350 c.i.d.V8
T.P.I. auto & standard transmission (dual converters)
INSTRUCTIONS
© 1997 Edelbrock Corp. REV 8/97
®
• DISASSEMBLY
1. Disconnect negative cable from battery.
2. Raise vehicle and support with jackstands.
3. Use penetrating oil on all nuts and bolts to be removed. This will
prevent the possibility of broken or stripped nuts and bolts.
4. Making sure converters are cool, remove the exhaust pipe and
catalytic converter assembly. NOTE: The small A.I.R. tube connection
should be a slip joint, however, the factory clamp is usually over-
tightened until is crushes the joint. If yours is stubborn, apply heat
from a torch to help loosen it.
5. Lower vehicle to the ground.
• DISASSEMBLY LEFT SIDE
1. Remove air cleaner system (note position of line and hose
connections).
2. Disconnect A.I.R. (air injection reactor) hose from exhaust manifold.
3. Remove air conditioner compressor rear support bracket. If air
conditioning compressor is mounted on right side of engine, this
bracket will require bending in a vice before re-installation (see
Figure 1).
4. Remove power steering pump support bracket (if power steering is
applicable).
5. Disconnect spark plug wires and remove spark plugs.
6. Remove 02sensor, being careful not to rupture or destroy the unit.
WARNING: Do not clean this unit in any cleaning solvents and do not
rupture wire.
7. Disconnect temperature sensor wire at cylinder head.
8. Remove temperature sensor wire support bracket from valve cover
bolt and lay wire back over engine.
9. Remove bolts and exhaust manifold from top side.
10. Disconnect steering column connector and lower slip tube down to
steering box. CAUTION: Do not turn steering wheel or front wheels
while this system is disconnected. USE EXTREME CAUTION IF
VEHICLE IS EQUIPPED WITH AIR BAG!
Clamp in vice, then bend flats approximately 10°
Figure 1—Right side A/C support rod- top view
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• PLEASE study these instructions carefully before installing your new Tubular Exhaust System (TES). If you have any questions or problems, do not
hesitate to contact our Technical Hotline at : 1-800-416-8628.
• TUBULAR EXHAUST SYSTEM: These components are designed as a system to improve the exhaust efficiency of the GM T.P. I. (tuned port injection)
V8 engine. A performance gain can be expected by the installation of the system. This system does require welding for installation and retains
all O.E.M. emissions equipment.
• SUGGESTED TOOLS FOR INSTALLATION: This vehicle has some metric fasteners
— MIG welder (recommended) or gas welder. Professional welding is highly recommended.
— 3/8” ratchet socket set with extensions and universal 13mm and 15mm swivel socketsI
— Combination set of open-end wrenches
— Jackstands, screwdrivers, pliers, crescent wrench, hacksaw, etc.
— Liquid penetrant, (GM #1052627) anti-seize compound (GM #5613695)
— Spark plug wire crimping tool
• SPECIAL NOTICE: This Edelbrock part has received an Executive Order number (E.O. #) from the California Air Resources Board (C.A.R.B.) making
it legal for street use on pollution-controlled motor vehicles in all 50 states. To assist you with emissions equipment certification, we have included
a silver fan shroud decal to verify that this part is a legal replacement part on the vehicle for which it is cataloged. The adhesive-backed decal
should be affixed to your fan shroud next to the existing emission and engine specification decal. Do not cover your original equipment specification
decal with the Edelbrock fan shroud decal.
• WARNING: The use of “Thermal Wrap” or any aftermarket coating process will void the warranty on your Tubular Exhaust System. Those products
can cause excessive heat and moisture buildup resulting in corrosion and early failure of the system.
• NOTES: The paint used on non-coated T.E.S. is for protection during shipping and storage and will burn off soon after the engine is started. Those
who desire a longer lasting finish should sand blast the T.E.S. to remove the original paint, then apply high temperature header paint, such as VHT,
available at most auto parts stores.
• When cleaning any Edelbrock Pro-Tech coated TES, use only soap and warm water. The use of caustic solvents (Gunk, etc.) will mar or damage
the Pro-Tech coating.
• High temperature spark plug wires and boots are recommended to withstand heat from T.E.S.

• DISASSEMBLY RIGHT SIDE
1. Disconnect A.I.R. injection hose from exhaust manifold and catalytic
converter tube.
2. Disconnect electrical connector and vacuum hoses from A.I.R.
diverter valve assembly (note position of hose and electrical
connections).
3. Remove A.I.R. pump feed hose from diverter valve assembly.
4. Remove nut from diverter valve support bracket at exhaust manifold
and loosen lower alternator pivot bolt, then remove diverter valve
assembly.
5. Disconnect spark plug wires and remove spark plugs.
6. Remove dip stick/tube from engine. CAUTION: Do not damage tube.
7. Remove bolts and exhaust manifold from top side.
8. At this time clean exhaust flange surfaces on cylinder heads.
9. Unbolt oil coolant tube from frame rail (where applicable) and bend
rear brace around tube. Bolt new flat brace (supplied) to frame rail.
This will move coolant tube above and on top of frame which will
allow more clearance for exhaust system.
• ASSEMBLY LEFT SIDE
1. Install T.E.S. flange gasket and one 3/8” 16 x 1” bolt and lock washer
at rearmost bolt hole (leave bolt loose enough to accept T.E.S.).
2. Install left side T.E.S. manifold from top side.
3. Install all but the front three bolts and washers on left side (do not
tighten at this time).
4. install rear power steering support bracket. Do not tighten.
5. Reinstall rear A/C support bracket with bolts, lock washers and
spacers supplied (see Figure 2 for spacer locations).
6. Align all parts and tighten left side bolts and nuts at this time.
7. Re-connect steering column coupler. WARNING: Make sure coupler
bolt is tight and check to see that steering wheel is in same
orientation as prior to disassembly.
8. Form brake lines to clear T.E.S. pipes where necessary; do not
disconnect.
9. Reinstall spark plugs and re-connect wires left side.
10. Change spark plug wire ends and boots as needed.
11. Reinstall temperature sensor wire support bracket and re-connect
wire to temperature sensor.
•ASSEMBLY RIGHT SIDE
1. Install T.E.S. flange gasket and one 3/8” - 16 x 1” bolt and lock
washer at rearmost bolt hole (leave bolt loose enough to accept TES.).
2. Install right side T.E.S. manifold from top side with dip stick tube at
same time.
3. Install remaining bolts, lock washers and dip stick tube clamp. (see
Figure 3) Do not tighten bolts at this time.
4. Re-install O.E.M. front stud bolt with spacer (supplied). Align all parts
and tighten all right side bolts at this time.
5. Re-install spark plugs and re-connect wires.
6. Change spark plug wire ends and boots as needed.
7. Reinstall diverter valve assembly in front O.E.M. stud bolt and tighten.
8. Re-connect electrical connections and vacuum lines to diverter valve
assembly.
9. Remove A.I.R. check valves from O.E. manifolds and reinstall them on
T.E.S. For 1986 & 1987 models, use plastic connector and 5” hose
supplied. Re-connect air hoses. For 1988 models remove 1/2” from
formed 900 rubber O.E.M. elbow and install plastic connector. Use 2”
of hose supplied and re-connect air hose. Re-connect all injection
hoses at this time.
10. Raise vehicle and support with jackstands.
•EXTENSION PIPE PREPARATION
1. The exhaust pipe/catalytic converter assembly must be cut off with a
hack saw as shown in Figures 4, 4a, and 4b. Note that the tab which
is welded to both pipes must be cut off of the right side pipe only and
will be re-welded to the new pipe after it is in place.
2. With gasket in place, bolt right side T.E.S. exhaust pipe to manifold
leaving bolts loose enough to align pipe.
3. Put catalytic converter/exhaust pipe assembly back into original
position, slipping right pipe into T.E.S. extension pipe.
4. With gasket in place, bolt left T.E.S. pipe onto manifold and slip over
OEM pipe.
5. Position T.E.S. extension pipes against T.E.S. manifolds so that an
equal amount of donut gasket is showing all around the flare on both
pipes (see Figure 5). This assures correct alignment of the two parts
before welding the rest of the system.
6. Tighten bolts so pipes won't move and make sure the catalytic
converter assembly is up in the original position, then tack weld to
both extension pipes. MIG welding is recommended, but gas can be
used if MIG is not available. Each pipe should be tack welded in at
least three places.
7. Remove complete assembly and finish welding. Be sure to re-weld
the tab between both pipes.
8. Install new extension pipe/catalytic converter assembly.
9. Before re-attaching the A.I.R. pipe, clean the mating surfaces
thoroughly with sandpaper, wire brushes, etc. If the joint was difficult
to loosen, it may help to apply some grease before assembly.
• LOWER VEHICLE TO THE GROUND
1. Connect negative cable to battery. At this point, it would be a good
idea to look everything over and make sure nothing was missed in
assembly.
2. Start vehicle and bring up to normal operating temperature and check
for possible leaks.
3. Turn engine off and let cool. Tighten all bolts again.
• HARDWARE SUPPLIED
1— Manifold left side #25-9007
1— Manifold right side #25-9008
1— Extension pipe left side #25-9560
1— Extension pipe right #25-9561
1— 12” 02 sensor pig tail wire
1— Flange connector
1— Air hose Connector
2— Chevrolet V8 port gaskets
2— 2-1/2” donut gaskets
1— Air hose 5/8” I.D. x 5” long
3— Spark plug boots and ends (if needed)
1— Coolant tube bracket
1— Umpco clamp; 3/8" I.D.
1— Umpco clamp; 1-5/8" I.D.
4— 3/8” flat washers
12— 3/8” - 16 x 1” Header bolts
2— 3/8”- 16 x 2-3/4” Ferry bolts
1— Hex nut; 10-32
4— 3/8” - 16 x 2” Hex cap screws
1— 5/8” x .72 Spacer tube
2— 5/8” x 1.53 Spacer tube
1— 5/8” x 1.12 Spacer tube
1— Hex cap screw; 10-32 x 1"
1— Star washer; 3/16" internal
12— 3/8” Split lock washers
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Figure 4
OEM exhaust pipe/catalytic
converter assembly
End of bend
Cut 1-1/2"
from bend
Cut pipe between
two bends
Cut tab from this side
only- leave enough
material to weld to
new pipe
cats.
A.I.R. slip
connection
.720" spacer
Small Umpco clamp
10-32 Capscrew, nut, and washer
Large Umpco clamp
Figure 3
Right Side
Figure 2
Left Side
1.125" spacer
1.530" spacers - use if air conditioning
compressor is mounted on left side of engine
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Figure 5
Align extension pipe with T.E.S. manifold so that an even
amount of the donut gasket is visible all the way around
the flare before tightening bolts.
Figure 4a
After marking pipe to be cut, clamp
securely, then cut with hacksaw
Figure 4b
Top view of cutting procedure
Figure 6
View from under vehicle of exhaust pipes/dual
catalytic converter assembly after cutting and
jointing to T.E.S.
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