Gibson GP125S-1 User manual

GP125S-1
STAINLESS HEADER
HAS NO EGR FITTING
FORD EXCURSION 6.8L-V-10 2/4WD
FORD SUPERDUTY TRUCK
F250HD/F350 6.8L-V10 2/4WD
GIBSON HEADERS ARE 50 STATE SMOG LEGAL
2/2 Thank you very much for purchasing our Gibson header
for your vehicle.
If you need further assistance, please do not hesitate to call our Technical
Department at
[phone]
Monday through Friday
8:00 a.m. to 5:00 p.m. PST.
1270 WEBB CIRCLE CORONA, CA 92879

WHEN THESE INSTRUCTIONS ARE FOLLOWED PRECISELY, YOU
WILL FIND THE INSTALLATION OF YOUR EXHAUST SYSTEM TO
BE RELITIVELY SIMPLE. WE CANNOT OVER EMPHASIZE THE
IMPORTANCE OF ADHERING STRICTLY TO THIS PROVEN
APPROACH, AS IT WILL VIRTUALLY ELIMINATE ANY
DIFFICULTIES, WHICH YOU MIGHT OTHERWISE ENCOUNTER.
NOTE: INSTALLATION OF HEADERS ON VEHICLES WITH
CATALYTIC CONVERTERS AND/OR OTHER EMISSION CONTROL
EQUIPMENT MUST BE ACCOMPLISHED IN ACCORDANCE WITH
ALL GOVERNMENT REGULATIONS PERTAINING TO SUCH
EMISSIONS STANDARDS.
WARNING: MAKE CERTAIN YOU HAVE ENOUGH CLEARANCE
AROUND BRAKE, FUEL, AND ELECTRICAL LINES, ETC. IN SOME
CASES, IT MAY BE NECESSARY TO RELOCATE ITEMS WHICH
MIGHT BE ADVERSELY AFFECTED BY EXHAUST HEAT.
WARNING: INSTALLATION OF ANY TYPE OF "WRAPPING"
MATERIAL ONTO THE HEADERS WILL DESTROY THE HEAT
DISSIPATION PROPERTIES OF THE TUBING, CAUSING
PREMATURE DETERIORATION OF THE METAL AND SUBSEQUENT
FAILURE. USE OF ANY "WRAPPING" MATERIAL WILL VOID THE
WARRANTY.

SUGGESTED TOOLS
7/16” WRENCHES (VARIOUS LENGTHS)
7/16” SOCKETS (SHALLOW AND DEEP)
½” WRENCHES (VARIOUS LENGTHS)
9/16” SOCKETS (SHALLOW AND DEEP)
5/8” SPARK PLUG SOCKET
7/8” OPEN END WRENCH
15MM DEEP SOCKET
15MM BOX END WRENCH
31MM OPEN END WRENCH (A LINE WRENCH)
3”, 6”, AND 12” EXTENSIONS FOR SOCKETS
SCREWDRIVERS AND/OR NUT DRIVERS (FOR HOSE CLAMPS)
SAWZALL (HAND –HELD POWER HACK SAW)
LUG NUT WRENCH
HIGH TEMP SILICONE (ULTRA COPPER BY PERMATEX)
GOOD RUST PENETRANT

INSTALLATION INSTRUCTIONS
NOTE:INSTALLATION OF THESE HEADERS REQUIRES AN ADEQUATE WORK SPACE, GENERAL
MECHANIC'S TOOLS, GENERAL MECHANIC "KNOW-HOW" AND A REASONABLE DEGREE OF
EXPERIENCE.
1. PLACE VEHICLE IN A LOCATION WHERE THE FLOOR IS SOLID AND FLAT, WITH
ADEQUATE LIGHTING. DO NOT ATTEMPT TO WORK ON A HOT ENGINE. HEAT CAUSES
METAL TO EXPAND AND MAKES REMOVAL OF FASTENERS DIFFICULT. DISCONNECT
THE BATTERY CABLES FROM THE BATTERY. RAISE THE FRONT OF THE VEHICLE TO
OBTAIN ADEQUATE ACCESS TO THE BOTTOM EXHAUST MANIFOLD FLANGES.USE
LARGE-BASED JACK STANDS TO SUPPORT THE VEHICLE. DO NOT RELY ON THE
JACK! BLOCK THE TIRES TO PREVENT THE VEHICLE FROM ROLLING OFF THE
JACKSTANDS. THEN UNBOLT AND REMOVE THE FRONT WHEELS.
2. SPRAY WD-40 OR SOME TYPE OF PENETRATING OIL ON ALL ACCESSIBLE
FASTENERS AND FITTINGS BEFORE ATTEMPTING TO REMOVE THEM.
3. FROM UNDERNEATH THE VEHICLE, LOOSEN THE BOLTS CONNECTING THE
EXHAUST SYSTEM TO THE EXHAUST MANIFOLD.SEE PICTURE #1 (ON 4X4 MODELS,
DISCONNECT THE FRONT DRIVESHAFT BY REMOVING THE 4 BOLTS ON THE FLANGE,
AND LET THE DRIVESHAFT HANGOUT OF THE WAY.) PRY THE EXHAUST SYSTEM
BACK ABOUT 1/2" TO GAIN WORK SPACE.FOR AN EASIER REMOVAL OF THE
MANIFOLDS OR INSTALLATION OF THE HEADERS. RECOMMENDED REMOVING
FACTORY Y-PIPE. BE CAREFUL TO NOT DAMAGE THE FACTORY GASKET IN FRONT OF
THE CATALYTIC CONVERTER WHEN REMOVING Y- PIPE. THE GASKET MUST BE RE-
USED. ALSO UNPLUG THE O2 SENSOR ON BOTH SIDES BEFORE REMOVAL OF THE Y-
PIPE. SEE PICTURE’S #1A & 1B
4. IT IS NOT NECESSARY TO REMOVE THE INNER FENDERWELLS, BUT IT MAKES THE
INSTALL EASIER. TO REMOVE THE FENDERWELLS SIMPLY UNSCREW ALL THE SHEET
METAL SCREWS AND FASTENERS ATTACHING IT TO THE FENDER AND FRAME AND THE
FENDERWELL WILL DROP OUT.
5. WORKING THROUGH THE WHEEL WELL, ON THE DRIVER'S SIDE, LOOSEN THE EGR
TUBE FROM THE MANIFOLD AND DISCONNECT IT FROM THE MANIFOLD. SOME V-10
MODELS DID NOT COME WITH A EGR TUBE. SO USE SUPPLIED EGR PLUG AND PLUG
EGR HOLE IN HEADER.SEE PICTURE #2 THEN LOOSEN THE EGR VALVE ON TOP OF THE
INTAKE MANIFOLD. (DO NOT REMOVE ONLY LOOSEN). THEN REMOVE THE NUTS
DISCONNECT MANIFOLDS
AT THIS POINT.
1.
DISCONNECT Y-PIPE AT THE FLANGE
CONNECTION IN FRONT OF THE
CATALYTIC CONVERTER.
1A.
O2 SENSOR PLUG.
1B.

ATTACHING THE MANIFOLD TO THE HEAD. REMOVE THE MANIFOLD.YOU MUST ALSO
REMOVE THE MANIFOLD ATTACHING STUDS FROM THE HEAD. THE STUDS HAVE A 5mm
HEX END ON THEM, A 1/4" DRIVE RATCHET AND A 5mm SOCKET WORK WELL FOR
REMOVING THE STUDS.
6. THE DIPSTICK MUST NOW BE REMOVED. IT HAS A SEPARATE MOUNTING BOLT ON
THE HEAD AND USES AN O-RING SEAL AT THE BOTTOM. USE CARE TO PROTECT THE
O-RING. REMOVE STOCK EGR FITTING FROM THE DRIVER’S SIDE MANIFOLD USING WD-
40, AND THEN INSTALL INTO HEADER (SHOWN ON PICTURE 2A), USE ANTI-SEIZE ON
THE FITTING FOR EASIER INSTALLATION.
7. BEFORE REMOVING THE PASSENGER SIDE MANIFOLDS REMOVE THE THREE BOLTS
HOLDING THE STARTER TO THE BELL HOUSING FOR AN EASIER REMOVAL OF THE
MANIFOLD AND INSTALLATION OF THE HEADERS. SEE PICTURES #3 & 3A. ON THE
PASSENGER SIDE,AGAIN WORKING THROUGH THE WHEEL WELL, REMOVE THE NUTS
ATTACHING THE MANIFOLD TO THE HEAD THEN REMOVE THE MANIFOLD.
REMOVE THE MANIFOLDS ATTACHING STUDS.
8. USING A SCRAPER REMOVE ALL CARBON DEPOSITS AND HIGH SPOTS FROM HEAD
SURFACE, USE CARE NOT TO GOUGE THE ALUMINUM HEADS.
9. NOTICE ON THE DRIVERS SIDE HEADER THE BOTTOM BOLT HOLES ARE SLOTTED.
INSTALL THE GASKET WITH THE HEADER BOLTS LEAVING AT LEAST 3/8 OF INCH GAP.
10. BEFORE INSTALLING THE HEADER. APPLY A SMALL AMOUNT OF HI-TEMP SEALER
TO THE EXHAUST PIPE FLARE THEN INSTALL THE DRIVER SIDE HEADER FROM
UNDERNEATH THE VEHICLE. SOME TWISTING AND WIGGLING OF THE HEADER IS
NECESSARY. AFTER INSTALLING THE HEADER RE-INSTALL THE DIPSTICK BEFORE
THE EGR TUBE.
EGR FITTING.
2.
BOLTS
NEEDED TO
BE REMOVED
FOR REMOVAL
OF THE
STARTER.
3.
3A.
2A.
EGR PLUG
IN HEADER

11. BEFORE INSTALLING THE PASSENGER SIDE HEADER. NOTICE ON DRIVER AND
PASSENGER SIDE HEADER, THERE ARE SLOTTED BOLT HOLES ON THE BOTTOM ALSO
ON THE FLANGE.INSTALL NEW BOLTS WITH THE GASKET LEAVING AT LEAST 3/8 OF
INCH GAP THEN INSTALL THE HEADER.
12. APPLY A SMALL AMOUNT OF HI-TEMP SEALER TO THE EXHAUST PIPE FLARE, THEN
INSTALL THE PASSENGER SIDE HEADER THROUGH THE WHEELWELL. ATTACH
USING THE SUPPLIED BOLTS AND GASKETS. APPLY A SMALL AMOUNT OF ANTI-SEIZE TO
THE THREADS OF THE BOLTS BEFORE TIGHTENING.THEN RE-INSTALL THE STARTER
INTO THE BELL HOUSING.
13. RE-CONNECT THE EXHAUST SYSTEM TO THE NEW HEADERS USING THE
HARDWARE PROVIDED.(RE-CONNECT DRIVE SHAFT WHERE APPLICABLE)WHEN RE-
ATACHING THE FACTORY Y-PIPE USE A SMALL AMOUNT OF GASKET SEALER AT THE
FLANGE GASKET BEHIND THE CONVERTER. THEN RE-PLUG THE O2 SENSOR’S IN.
14. RE-INSTALL THE INNER WHEELWELLS (IF REMOVED). CHECK TO ENSURE THAT
THERE ADEQUATE CLEARANCE ON ALL BRAKE LINES, WIRE LOOMS, A/C LINES,
ETC. IT IS RECOMMENDED THAT YOU REMOVE THE PASSENGER SIDE WHEEL WELL
FLAP.
15. RE-INSTALL THE FRONT WHEELS AND TORQUE TO FACTORY SPECS.
(SEE OWNER'S MANUAL).
16. RECONNECT THE BATTERY.
17. RE-CHECK EVERYTHING!
18. START THE ENGINE, CHECK FOR LEAKS AND TEST DRIVE. THEN LET THE ENGINE
COOL AND THEN RE-TORQUE THE HEADER BOLTS.
19. PERIODICALLY CHECK AND RETIGHTEN THE HEADER BOLTS.
NOTE: IT IS NOT UNUSUAL WHEN INSTALLING HEADERS TO GET A BURNING
SMELL. THIS IS NORMAL AND IT WILL GO AWAY!
PARTS LIST:
(1) DRIVER'S SIDE HEADER ASSEMBLY
(1) PASSENGER'S SIDE HEADER ASSEMBLY
(2) HEADER GASKETS (HEADER TO HEAD FLANGE)
(4) COLLECTOR BOLTS AND NUTS,WASHERS
(20) 8mm X 1.25mm BOLTS WITH STAR WASHERS
(1) EGR PLUG

IT IS CRITICAL THAT ALL BOLTS BE RE-TIGHTENED HOT AFTER ABOUT 20
MINUTES OF OPERATION TO PREVENT GASKET FAILURE.
NOTE: HEADERS ARE NOT MEANT TO SERVE AS “EXHAUST SYSTEM SUPPORT
HANGERS”. ADDITIONAL HANGERS MAY NEED TO BE ADDED AT THE TIME OF THE
INSTALLATION OF THE HEADERS SO THAT THE EXHAUST SYSTEM SUPPORTS
ITSELF WHEN THE COLLECTOR BOKTS ARE REMOVED. HEADERS THAT HAVE
“SAGGED” DUE TO THE LACK OF SUFFICIENT EXHAUST SYSTEM SUPPORT WILL
NOT BE REPLACED UNDER WARRANTY.
NOTE: HEADER BOLTS SHOULD BE INSPECTED FOR TIGHTNESS FROM TIME TO
TIME TO ENSURE OPTIMUM GASKET LIFE. THE BOLTS WILL STRETCH SOME AT
FIRST DUE TO THE EXHAUST HEAT; SO, THEY’LL LOOSEN WITHOUT TURNING
UNTIL THEY “TAKE A SET”. (BOLTS HARD ENOUGH NOT TO STRETCH WOULD
BREAK!) WE’VE EXPERIMENTED WITH THE VARIOUS “LOCKING DEVICES” ON THE
MARKET, WHICH PREVENT BOLTS FROM TURNING. THEY DON’T WORK ON HEADER
BOLTS, AND THEY GREATLY COMPLICATE THE PROCESS OF RE-TIGHTENING THE
BOLTS WHEN IT’S NECESSARY.
WHAT DOES WORK IS THIS:
GO OVER THE BOLTS AGAIN AFTER THE FIRST DAY OF DRIVING (OR ABOUT 100
MILES-WHICHEVER COMES FIRST) THEN AFTER THE FIRST WEEK, AFTER THE
FIRST MONTH, AND THEN EVERY 6 MONTHS. OUR EXCLUSIVE GASKETS ARE
SPECIALLY MADE SO THAT THE CYLINDER HEAD SHOULD BEGIN TO MELT BEFORE
THE GASKETS CAN BURN UP. ABOUT THE ONLY WAY TO KILL THE GASKETS IS TO
LET THE HEADERS GET LOOSE AND THEN KEEP DRIVING WITH A LEAK.
DUE TO VARYING CONDITIONS BETWEEN GEOGRAPHICAL LOCATIONS AND USAGE,
WE STRONGLY RECOMMEND HAVING THE ENGINE RE-TUNE AT A REPUTABLE TUNE-
UP SHOP AFTER THE INSTALLATION OF THE HEADERS. DOING SO WILL ENSURE
THAT YOU GET THE MAXIMUM BENEFIT FROM THE INSTALLATION OF THE
HEADERS.
GIBSON PERFORMANCE STRIVES TO DELIVER THE HIGHEST QUALITY MATERIALS,
WORKMANSHIP, AND SERVICE. PLEASE DO NOT HESITATE TO CALL OUR
TECHNICAL LINE IF YOU HAVE A QUESTION OR EXPERIENCE A PROBLEM.
WE TRULY WISH TO HAVE ONLY SATISFIED CUSTOMERS