Edelbrock 66673, 66662, 66663, 66672, 68012 User Manual

TUBULAR EXHAUST SYSTEM

Catalog #s 66662, 66663, 66672, 66673, 68012, 68013

Vehicle Applications - See Below

INSTALLATION INSTRUCTION

Please study these instructions carefully before installing your new Tubular Exhaust System (TES). If you have any
questions, please contact our Technical Hotline at : 1-800-416-8628 from 7 am - 5pm, Monday-Friday, Pacific
Standard Time or e-mail us at [e-mail]. Please fill out and mail your warranty card.

APPLICATIONS:

#66662, #66663: 1992-1993 Blazer 5.7L TBI

1988-1995 GMPick-Up 5.0L &5.7L TBI
1992-1995 Suburban 5.0L & 5.7L TBI

#66672, #66673: 1988-1995 GM Pick-Up 5.0L & 5.7L TBI

NOTE: All of the following vehicle applications are for 2 & 4 WD, Automatic and Standard
Transmission without A.I.R., Clamp-On Catalytic Converter:

#68012, #68013: For lowered trucks - fits same application as #66662, #66663

TUBULAR EXHAUST SYSTEM: These components are designed as a system to improve the exhaust efficiency of the GM
T.B.I. (Throttle Body Injection) V8 engine. A performance gain can be expected by the installation of the system. This
system requires no welding for installation and retains all O.E. M. emissions equipment.

Suggested Tools Needed for Installation: This vehicle has some metric fasteners.

❑ 3/8” rachet socket set with extensions and universal 13mm and 15mm swivel sockets
❑ Combination set of open-end wrenches
❑ Jackstands, screwdrivers, pliers, crescent wrench, etc.
❑ Liquid penetrant, (GM #1052627) and anti-seize compound (GM #5613695)

NOTE: Some models will require special power steering pulley puller, K-D 2897 or equivalent.

SPECIAL NOTICE: This Edelbrock Tubular Exhaust System has received an Executive Order number (E.O.#) from the

California Air Resources Board (C.A.R.B.) making it legal for street use in all 50 states. To assist you with emission
equipment certification, we have included a silver fan shroud decal to help testing personnel verify that this part is a legal
replacement on the vehicle for which it is cataloged. The adhesive-backed decal should be affixed next to the existing
emission and engine specifications decal. Do not cover any part of your original emission decal.

WARNING: The use of "Thermal Wrap" or any aftermarket coating process will void the warranty on your Edelbrock
Tubular Exhaust Systems. Those products can cause excessive heat and moisture buildup resulting in corrosion and
failure of the system.

INSTALLATION INSTRUCTIONS

DISASSEMBLY

1. Disconnect negative battery 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 stipped nuts and bolts.

4. Making sure the converter is cool, remove the
exhaust crossover pipe.

5. Lower vehicle to the ground.

DISASSEMBLY - LEFT SIDE

6. Remove air cleaner system (note position of line and
hose connections).

7. Disconnect A.I.R. (Air Injection Reactor) tube from
exhaust manifold (#66672, & 66673 only).

8. Remove airconditioner compressor rear support
bracket (ir airconditioning equipped).

9. Remove power steering pump support bracket (if
power steering is applicable). In order to remove the

Catalog #s 66662, 66672, 66663, 66673, 68012, & 68013
©2005 Edelbrock Corporation

Page 1 of 3

Brochure #63-0447

Rev. 9/05 - DA/mc

OEM bracket attached with the 2 front exhaust
manifold bolts on some models, it may be necessary
to remove the power steering pump pulley. This
require the use of a special power steering pulley
puller, such as K-D 2897 or equivalent.

10. Disconnect spark plug wires and remove spark
plugs.

11. Remove O2 sensor, being careful not to rupture or
destroy the unit.

WARNING: Do not clean this uni in any
cleaning solvent and do not rupture wire.

12. Disconnect temperature sensor wire.

13. Remove bolts and exhaust manifold from top side.

DISASSEMBLY - RIGHT SIDE

14. Disconnect A.I.R. injection tube from exhaust
manifold (#66672, #66673 only.

15. Disconnect spark plug wires and remove spark
plugs.

16. Remove bolts and exhaust manifold from top side.

17. Clean exhaust flange surfaces on cylinder heads at
this time.

ASSEMBLY - LEFT SIDE

1. Install T.E.S. flange gasket and one 3/8”-16 x 1” bolt,
lock washer, and flat 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 two bolts and washers on left
side (do not tighten at this time).

4. Re-install rear power steering support bracket. Do
not tighten at this time.

5. Re-install accessory bracket which mounts to the
first two bolt holes on left side with 2-3/4” ferry
bolts, lock washers, and 1-1/2” spacers supplied.
Use the spacers only between the manifold flange
and the accessory bracket; use a 3/8” lockwasher
under th eahd of the ferry bolt.

6. Align all parts and tighten left side bolts and nuts at
this time.

7. Re-install spark plugs and re-connect wires on left
side.

8. Re-install temperature sensor wire to temperature
sensor.

9. Re-install O2 sensor. Use anti-seize on threads of
sensor and torque to 30 ft./lbs. Re-route O2 sensor
wire from wire loom to O2 sensor making sure all
wires are clear of exhaust system (O2 sensor
extension wire is included in kit).

ASSEMBLY - RIGHT SIDE

1. Install T.E.S. flange gasket and one 3/8”-16 x 1”
bolt, lock washer and flat washer at rearmost bolt
hole (leave bolt loose enough to accept T.E.S.).

2. Install right side T.E.S. manifold from top side.

3. Install remaining bolts, lock washers, and spacer
tube dipstick to clear exhaust flange.

4. Align all parts and tighten all right side bolts at this
time.

5. Re-install spark plugs and re-connect wires.

6. Remove A.I.R. check valves from original manifolds
and re-install them on T.E.S. With hose supplied in
kit, re-connect all A.I.R. injection hoses at this time
(#66672, & #66673 only).

7. Raise vehicle and support with jackstands.

CROSSOVER PIPE ASSEMBLY

1. Select the correct adapter tube for your catalytic
converter (small diameter for 5.0L and large
diameter for 5.L engine).

2. Carefully align and tap adapter tube into converter
using a piece of wood or a mallet to protect the end
of the adapter.
NOTE: Be sure adapter goes all the way in,
approximately 2-1/2”.

3. Install crossover pipe assembly on vehicle using four
3/8” x 2” bolts with lock washers and donut gaskets
supplied.

4. Install U-clamps and position for maximum ground
clearance, then tighten all nuts and bolts.

Catalog #s 66662, 66672, 66663, 66673, 68012, & 68013
©2005 Edelbrock Corporation

Page 2 of 3

Brochure #63-0447

Rev. 9/05 - DA/mc