Details
Thorley headers are designed to outflow your stock exhaust manifolds. These headers increase gas mileage and give your engine more horsepower across the entire rpm range. The Tri-Y configuration builds the most power in the middle rpm range, which is great for towing and steep grades. To make these headers last, Thorley made them out of durable 14-gauge mild steel with 3/8 in. thick flanges and 5/16 in. collector rings. To prevent leaks, these headers have an O-ring welded into the flange, in addition to the high-temperature gasket provided. 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.
Header Style: Tri-Y
Header Material: Steel
Header Finish: Silver ceramic coated
Primary Tube Diameter (in): 1 5/8 in.
Collector Attachment: 3-bolt flange
Collector Diameter: 2.500 in.
Tuned: No
Primary Tube Gauge: 14-gauge
Flange Style: Standard
Flange Thickness (in): 3/8 in.
Bolts/Studs Included: Yes
Gaskets Included: Yes
Reducers Included: No
Y-Pipe Included: No
Motor Mounts Included: No
Transmission Mount Included: No
Quantity: Sold as a pair.
Drivetrain RWD
Power Steering Yes
Power Brakes Yes
Air Conditioning Yes
Standard Transmission Column Shift No
Standard Transmission Floor Shift Yes
Automatic Transmission Column Shift Yes
Automatic Transmission Floor Shift Yes
Application Footnotes: 5 - Vehicles equipped with power steering slave cylinders will require power steering drop bracket DTE-8500.
8 - Will fit console shift only.
Vehicle Type Group Automotive
Additional Information
| year make model | 1964-1970 Ford Mustang and Mercury Cougar thy289yc |
|---|---|
| Manufacturer | DOUG THORLEY HEADERS |


