GMC CK Pickup 5.7L Automatic Transmission 1996-1998, 4-2-1 Tri-Y Exhaust Header Kit with Complete Connector Pipes by Doug Thorley Headers®. Primary Tubing Diameter: 1.625". Collector Outlet Diameter: 2.5". Emissions: CARB compliant. Backed by over 50 years of knowledge and experience, Doug's headers are designed to outflow your stock exhaust manifolds by leaps and bounds. Tri-Y (or 4 into 2 into 1) style headers by design will increase the power of your motor across the widest RPM band possible. That is the beauty of the design, and that is why they are the best street header available. To make these headers last, Doug's built them using industry leading 14-gauge mild steel tubing with 3/8" thick flanges. To top all of that off, all of Doug's headers come beautifully ceramic coated to greatly reduce under-hood temperatures and protect the headers from the environment. All 100% American made, and backed by Doug's lifetime warranty of course! Unless otherwise noted, these headers are designed to fit the vehicle as it came from the manufacturer. This includes components like cylinder heads, chassis, steering, motor mounts, body mounts and bushings, etc. If your vehicle is using aftermarket components, parts from other applications, or custom altered parts, then it is the installer's responsibility to verify fitment. This product is made of high-quality materials to serve you for years to come. Designed using state-of-the-art technology and with customers in mind. It will meet your needs and deliver great quality at an affordable cost.
Fitment notes: This is a CARB compliant part, legal for use on vehicles built to meet CARB standards and/or registered in California and other states which follow CARB standards.
|Primary Diameter: 1.625"|
|Collector Diameter: 2.5"|
|Emissions: CARB compliant|
|Header Style: 4:2:1 Tri-Y Header|
|Finish: Silver Ceramic Coated|
|Weld Up: No|
|Primary Tube Diameter (in): 1-5/8"|
|Primary Tube Gauge: 14 Gauge|
|Collector Attachment: 3-Bolt Flange|
|Collector Diameter: 2-1/2"|
|Flange Thickness: 3/8"|
|Bolts and/or Studs Included: Yes|
|Gaskets Included: Yes|
|Reducers/Adapters Included: No|
|Y-Pipe (Crossover) Included: Yes|
|Quantity: Sold as a Complete Kit|
|Warranty: Limited Lifetime to original purchaser|
The Tri-Y Headers is designed with an emphasis on maximum low and mid range torque, while making ample horsepower throughout the RPM range. The 4:2:1 Tri-Y headers design makes it the ideal choice for trucks, tow-rigs, RV's and most street applications. The collector design makes this header one of Doug's most efficient, which means you'll see improvements both on the dyno and at the pump.
A Doug Thorley Headers original design, the 4:2:1 collector specification on the Tri-Y Headers is engineered to match your engine's firing order and thereby maximize exhaust scavenging - the complete expulsion of gasses on the exhaust stroke. The Tri-Y design creates more usable power and torque than any other headers design, making it the headers of choice for enthusiasts who want the most bang for their buck.
For over 50 years, Doug Thorley Headers has been an innovator in the automotive aftermarket. Driven by a passion for performance and superior quality, they are committed to developing 100% American-made products that will reliably deliver maximum horsepower and torque. Doug Thorley Headers® has been pushing the limits of automotive technology since they first invented the Tri-Y header in 1958, and they do it all on American soil.