Product: Corvette Tri-Y Headers & Mid-Pipe Part Numbers: Complete Kits: 1150042 C5 Base/Z06 Complete Header Package with Cats 1150043 C5 Base/Z06 Complete Header Package without Cats Applications: Chevrolet Corvette, 1997-2004 Description: These Tri-Y Headers and Mid-Pipe are engineered to be a high performance exhaust system for C5 Corvettes. Proper runner lengths, merge angles, and tube diameters have been combined to provide maximum scavenging and maximum power from LS engines. Rev. 10/28/2013
What s in the box: Item Qty Left Header 1 Right Header 1 Mid-Pipe 1 Header Bolts 12 O 2 Sensor Bung Plug 1 V-Band Clamps 2 Over-Axel Fasteners 4 Difficulty of Installation: Beginner -----------------------------------x--------- Advanced Reason: This product involves careful fitment and the use of a lift is recommended. Expected Installation Time: 4 Hours Recommended Tools: 3/8 drive ratchet & extensions 1/2 drive ratchet & extensions 13mm wrench 15mm wrench 22mm wrench 10mm socket 13mm deep well socket 15mm deep well socket 21mm deep well socket 5/8 Spark plug socket 10mm hex bit socket Various ratchet extensions and swivels Torque wrench Mechanics hook or pick Anti-Seize compound 2
Prepare Vehicle for Service This installation should be performed by a professional installer. If you do not have proper tools, safety equipment, and training you run the risk of injuring yourself of damaging your car. The use of a lift is strongly recommended to perform this installation. It is highly recommended to spray various nuts and bolts in the factory exhaust with a penetrant such as PB Blaster or WD40 and allow it to soak for a few hours to avoid seized or broken bolts. Step 1: Raise Vehicle Securely support the vehicle on a lift or 4 jack stands with at least 24 inches of clearance from the frame rail to the ground. Step 2: Disconnect Battery Remove the negative battery cable to battery nut and separate the cable from the battery. Step 3: Remove Fuel Rail Covers Carefully pull upward on the plastic fuel rail covers to remove them and set them aside. Step 4: Remove Spark Plugs Remove the spark plug wires and spark plugs to avoid damaging them during installation (5/8 spark plug socket). Step 5: Remove Dipstick Tube Remove the bolt securing the tube to the head and pull upward on the tube to unseat the bottom end from the oil pan (15mm socket). Step 6: Disconnect Steering Shaft Center the steering wheel and secure it. Remove the bolt pinching the steering u-joint onto the steering rack (15mm Socket). Slide the u-joint off the rack and move the steering rack up and out of the way. NOTE: DO NOT turn the steering wheel or tires while disconnected. This could result in steering column, airbag, or electronics damage. Step 7: Disconnect O 2 Sensors from Engine Wiring Harness Disconnect the primary and secondary O 2 sensors from the engine wiring harness. The connectors can be found near the rear of the engine block, and along the entrance to the Exhaust tunnel. Step 8: Remove Air Injection Piping from the Exhaust Manifolds For each exhaust manifold, remove the two bolts securing the tube to the manifold. (10mm 5pt Socket) and pull outward on the tube to unseat the flange from the Manifold. 3
The Air injection System will no longer be needed with your new Pfadt Tri-Y headers. The system can be disabled by removing the Air Pump Micro fuse #33 in the Engine Compartment fuse Box. OEM Exhaust Removal Step 1: Remove Factory Mid-Pipe Remove the two bolts securing the mid-pipe hanger springs to the mid-pipe (13mm deep well socket) near the rear of the mid-pipe. Also remove the two 13mm mid-pipe hanger bolts from the rear of the bell housing on the front of the mid-pipe. Remove the nuts and bolts attaching the mid-pipe to the cat-pipe (15mm deep well socket). Loosen the Nuts/Bolts from the diamond shaped flanges clamps connecting the mid-pipe to the overaxle (15mm deep well socket and open ended wrench). Carefully remove the mid-pipe from the vehicle. Step 2: Remove Exhaust Manifolds Remove the nuts securing the cat-pipe to the exhaust manifold and remove the cat-pipe.. NOTE: It may be necessary to raise the engine slightly from the subframe in order for the exhaust manifolds to be removed or for the flange on the cat-pipe to clear the studs on the manifold. To raise the engine, remove the two nuts securing the engine mount studs to the subframe. Raise the engine with a screw jack or floor jack, being careful to distribute the load across the bottom of the oil pan with a wood block or other method to avoid damaging the cast aluminum pan. Remove the six bolts securing each exhaust manifold to the head (13mm socket and short extension). Remove the manifolds and gaskets from the vehicle. Inspect the head surface and carefully clean it with a gasket scraper if needed. Take care not to gouge or scratch the sealing surface of the aluminum head. Step 3: Remove O 2 Sensors from Factory Exhaust Remove the primary and secondary O 2 sensors from the factory exhaust (22mm wrench). Retain the O 2 sensors for use in your Pfadt Power Products exhaust. 4
Pfadt Tri-Y Header Installation Procedure Step 1: Install the Primary O 2 Sensor Extensions Connect the O 2 sensor extensions to the engine wiring harness. The primary O 2 sensors connectors can be found at the rear of the block between the firewall low near the tunnel. Extension kits are available through Pfadt Race Engineering. Do not connect the actual O 2 sensors at this time, but it is recommended that you test fit your O 2 sensors in the weld bungs on the headers and mid-pipe (for catted systems). Some wideband O 2 sensors are too large to fit through the pre-drilled hole. If that is the case with your particular wideband sensor, carefully enlarge the hole as necessary with a hand file or carbide burr on a die grinder. Take care not to damage the threads in the bung! Step 2: Lower the Subframe With the engine mounts unbolted and the engine supported, remove the eight upper control arm bolts (13mm socket). Be sure to make note of how many washers are behind each bolt for reinstallation. Remove the four bolts holding the front shocks to the lower control arm (10 mm deep well socket and wrench). With the suspension unbolted and secured, remove the two front subframe bolts (21mm deep well socket) completely and loosen the two rear bolts (21mm deep well socket) holding up the subframe. Take care to keep a few threads engaged before you completely support the subframe and remove the bolts as needed to put the headers in place. Step 3: Install Driver Side Header Install the driver side header from the bottom of the vehicle. It may be necessary to raise the engine slightly to allow enough clearance to fit the header between the subframe and the side of the block. Take care not to damage the clutch or brake lines running along the firewall with the header flange during installation. Do not install the header bolts at this time; just leave the header sitting in place. Step 4: Install Passenger Side Header Install the passenger side header from the bottom of the vehicle. It may be necessary to raise the engine slightly to allow enough clearance to fit the header between the subframe and the side of the block. Take care not to damage the wiring harness heat sleeve running along the firewall with the header flange during installation. Do not install the header bolts at this time, just leave the header sitting in place. Be sure to route the AC line in such a way as to keep it at minimum 1/4inch from the header. Secure the AC in place. The hardline may be re-routed if needed, but only very small changes are recommended. 5
Step 5: Install Header Gaskets Install the header gaskets using the provided header bolts. DO NOT use any sort of gasket sealer on the header gasket. O 2 sensor and catalytic converter failure may result. NOTE: Cometic MLS gaskets must be installed in the correct orientation to avoid blocking any spark plug holes! Install them per the following illustrations to avoid any spark plug clearance issues. Driver Side Correct Gasket Orientation: Passenger Side Correct Gasket Orientation: Leave the header bolts somewhat loose to allow easier alignment of the V-band flanges with the mid-pipe. 6
Step 6: Install O 2 Sensors Apply a thin coat of anti-seize to the threads on all O 2 sensors. Install one primary O 2 sensor (4-pin connector) in each header (22mm wrench). It does not matter whether you install the factory O 2 sensor in the forward or rear bung in the passenger side header. If a wide-band O 2 sensor will be used, install it in the extra bung in the passenger side header. If no wide-band sensor will be used, apply anti-seize to the threads of the provided bung plug and install it in the extra bung (10mm hex bit socket). Connect the primary O 2 sensors to the extensions installed previously and tuck the wires out of the way of the headers. It is convenient to zip-tie the O 2 wires to the various fluid lines running along the tunnel to keep them away from the headers. If the Pfadt Tri-Y exhaust system has catalytic converters, install the secondary O 2 sensors (3-pin connectors) in the bungs in the mid-pipe (22mm wrench). If the exhaust system does not have catalytic converters you will no longer need the secondary O2 sensors. Step 7: Install Mid-Pipe Install the mid-pipe hanger bolts through the holes in the hanger bracket to the spring hangers. Torque the nuts to 18 ft-lbs (25 N-m) (13mm deep well socket). Align the V-band flanges on the headers with the flanges on the mid-pipe and install the V-band clamps. Tighten the nuts far enough to ensure the flanges won t slip out of the clamps, but leave them fairly loose for now (13mm deep well socket). 7
Install the provided diamond flange gasket at the mid-pipe/over axel connection. Once the mid-pipe hanger and V-bands clamps are tight; install the four provided 15mm fasteners. Step 8: Connect Secondary O 2 Sensors (only for mid-pipes with cats) Connect the secondary O 2 sensors to the extensions installed previously. It is OK for the sensors to cross and connect to the wiring harness on the opposite side of the car. The included heat resistant sleeve can be slipped over the connectors to protect them from the heat of the cats. Route the O 2 sensor wires at the corners of the transmission tunnel and secure them in place. Torque tunnel plate bolts to 89 in-lbs (10 N-m) (10mm socket, extensions). Tuck any remaining extension wiring out of the way of the headers and secure them as needed with zip ties. Step 9: Torque Header Bolts Torque the header bolts at first pass to 11 ft-lbs (15 N-m). Begin with the center two bolts and alternate from side to side, working toward the outside bolts. Torque them at final pass to 18 ft-lbs (25 N-m), again starting with the center bolts and alternating from side to side as you work outward toward the ends of the flange (13mm socket, various extensions). Step 10: Raise Subframe, Reinstall Suspension and Torque Fasteners Raise the subframe back into position and start the two front subframe bolts (21mm socket). With all 4 bolts started, slowly raise the subframe into place. Take care to ensure the engine mount bolts are aligned with the subframe and inserted correctly. When all 6 fasteners are aligned, raise the subframe completely into place and torque the fasteners. With the subframe in place, reinstall the four lower shock mount bolts into the lower control arms (10mm socket and wrench). Carefully lift the upright and upper control arm into place and replace the eights fasteners (four each side, 13mm socket). This is easily done near the ground with a jack under the lower ball joint. Be sure to put the correct number of washers in the correct location as noted during disassembly! Step 11: Torque Exhaust Fasteners Torque the diamond flange fasteners to 40 ft-lbs (54 N-m). Torque the V-band clamps to 12 ft-lbs (16 N-m) (13 mm deep well socket). 8
NOTE: To prevent thread galling, do not use a high-speed driver such as an impact gun on the V-band clamp nuts. Only tighten by hand and torque to spec. Step 12: Reinstall Dipstick Tube Reinstall the dipstick tube that was removed earlier in the installation. (15mm socket). Torque to 18 ft-lbs (25 N-m). Step 13: Reinstall Spark Plugs Reinstall the spark plugs and plug wires. If you have difficulty getting any spark plugs started in the holes, refer to the gasket installation step to ensure the header gaskets are not partially covering any of the plug holes. Step 14: Re-connect Steering Shaft With the steering wheel and tires centered, slide the u-joint on the steering column onto the steering rack with the flats aligned. Re-install the bolt pinching the steering u-joint onto the steering rack (15mm Socket). Torque to 48 ft-lbs (65 N-m) NOTE: Be sure the steering wheel and steering rack are centered before reconnecting the wheel to the rack. Failing to do so will cause damage to the steering column, airbag, or electronics. Step 15: Check for Leaks Double check that all fasteners have been tightened, wiring is not dangling on headers, spilled oil is wiped off headers, and that there is adequate clearance between the headers and any other components. Start the car and check for exhaust leaks, oil leaks, or coolant leaks. Congratulations, you have successfully installed your new Pfadt Power Products headers and mid-pipe and are now ready to reap the rewards of a carefully engineered exhaust system! 9
Fastener Torque Specifications Torque Spec Application Metric English Engine Mount Nuts 65 N-m 48 ft-lbs Mid-Pipe Hanger Nuts 25 N-m 18 ft-lbs Header Bolts (First Pass) 15 N-m 11 ft-lbs Header Bolts (Final Pass) 25 N-m 18 ft-lbs V-Band Clamps 16 N-m 12 ft-lbs Tunnel Plate Bolts 10 N-m 89 in-lbs Diamond Flange Bolt/Nuts 54 N-m 40 ft-lbs Subframe Bolts 65 N-m 48 ft-lbs Lower Shock Mounts 25 N-m 18 ft-lbs Upper Control Arm Mounts 32 N-M 24 ft-lbs Dipstick Mount Bolt 25 N-m 18 ft-lbs Steering Shaft Bolt 65 N-m 48 ft-lbs Please contact Pfadt Customer Support with any questions! Warranty and Use Restrictions Our warranty covers the workmanship and materials of the headers and mid-pipe for the original purchaser on the original vehicle of installation for five years. Headers and midpipes that are sold to another person or removed and installed on another car are excluded. Catalytic converters are covered for one year. Pfadt is not responsible for premature failure of a catalytic converter due to tuning/tuning related issues or other negligence on the part of the installer or end user. If you have a catalytic converter failure outside the limits of the warranty, we will ONLY charge you for the replacement of the cats and provide you with a free mid-pipe for up to 5 years from original date of purchase. Pfadt reserves the right to replace individual components. All Pfadt headers are for off-road use only. These exhaust systems are intended for use on racing vehicles (i.e. a competition vehicle used exclusively for competition on closed-course circuits) and do not require an exemption or Executive Order from CARB to be sold in California for such purpose. However, such parts are prohibited from use on many state s public roads, including California, even if occasionally used off-road. 10
1055 S 700 West Salt Lake City, UT 84104 888-972-2464 www.pfadtracing.com 11