Howards Cams® American Muscle™ Hydraulic Flat Tappet Camshaft
Near duplicates of some of the most iconic original equipment camshaft grinds from the '60's to the early '70's. Howards Cams™ took these fantastic grinds and made slight changes to the ramp speeds and minor duation changes to give you better reliability and horsepower. You still get the same throttle response and of course the original style exhaust rumble. Great cams for restoration projects and perfect for the street machines.
Note: Always use Camshaft Break-In Lube with all new flat tappet cams.
Manufactured on Dedicated High Precision Machines
Held to Strict Tolerances
High grade quality cores
Rockwell Tested & Parkerized Ensuring the Highest Quality
Includes Matching Premium Lifters
Part Type: Camshaft
Application: Chevrolet W-Series 348-409 1958-1965
Ignition Firing Order: OE (1-8-4-3-6-5-7-2)
Cam Style: Hydraulic Flat Tappet
Basic RPM Range: 800-4400
Manufacturers Description: American Muscle™, Near duplicate of the Chev 340HP/409 cam ( GM #3744901).
Intake Duration @ .050": 190
Exhaust Duration @ .050": 198
Advertised Intake Duration (@ .006"): 266
Advertised Exhaust Duration (@ .006"): 274
Intake Valve Lift with OE Rocker Ratio (1.75): .401"
Exhaust Valve Lift with OE Rocker Ratio (1.75): .411”
Intake Lobe Lift: .229
Exhaust Lobe Lift: .234"
Intake Valve Lift with 1.70 Rocker Ratio: .389"
Intake Valve Lift with 1.80 Rocker Ratio: .412"
Exhaust Valve Lift with 1.70 Rocker Ratio: .398"
Exhaust Valve Lift with 1.80 Rocker Ratio: .421"
Lobe Separation Angle: 113 Degrees
Intake Centerline: 110 Degrees
Lifters Included: No
Small Base Circle: No
Cam Gear Attachment: 3-Bolt
Valve Adjustment: Zero Lash Plus ˝ Turn
Manufacturer: Howards Cams & Racing Components
Manufacturer's Part Number: 137651-13
Weight: 10.0 lbs.
Warranty: Race Application, No warranty expressed or implied
Quantity: Sold as Each
Note: Oil with ZDDP or ZDDP Additive Required
Note: Stock (O.E.) valve springs can not be used. |