Howards Cams Steel Billet Mechanical Roller Camshafts 4/7 Swap
By switching the firing order (1-8-7-3-6-5-4-2) on your favorite Chev V8, you will discover a broader, smoother torque curve and decrease in crankshaft deflection. More aggressive profiles can be used to get the most manageable horsepower available. These cams require no additional engine modifications, other than swapping the #4 ignition wire with #7.
Manufactured on Dedicated High Precision Machines
Held to Strict Tolerances
High grade quality cores
Hard protective packaging
Part Type: Camshaft
Application: Chevrolet Big Block Mark IV 396-502 1965-1996
Ignition Firing Order: 4/7 Swap 1-8-7-3-6-5-4-2
Cam Style: Mechanical Roller
Basic RPM Range: 3800-7400
Manufacturers Description: Good mid-range torque & horsepower. 11.0:1+ CR.
Intake Duration @ .050": 267
Exhaust Duration @ .050": 273
Advertised Intake Duration (@ .020"): 299
Advertised Exhaust Duration (@ .020"): 305
Intake Valve Lift with OE Rocker Ratio (1.70): .731"
Exhaust Valve Lift with OE Rocker Ratio (1.70): .731"
Intake Lobe Lift: .430"
Exhaust Lobe Lift: .430"
Intake Valve Lift with 1.72 Rocker Ratio: .740"
Intake Valve Lift with 1.75 Rocker Ratio: .752"
Intake Valve Lift with 1.80 Rocker Ratio: .774"
Exhaust Valve Lift with 1.72 Rocker Ratio: .740"
Exhaust Valve Lift with 1.75 Rocker Ratio: .752"
Exhaust Valve Lift with 1.80 Rocker Ratio: .774"
Lobe Separation Angle: 108 Degrees
Intake Centerline: 104 Degrees
Small Base Circle: No
Cam Gear Attachment: 3-Bolt
Valve Adjustment Intake: .022"
Valve Adjustment Exhaust: .022"
Manufacturer: Howards Cams & Racing Components
Manufacturer's Part Number: 124203-08
Weight: 10.0 lbs.
Warranty: Race Application, No warranty expressed or implied
Quantity: Sold as Each
Note: Stock (O.E.) valve springs cannot be used.
Note: Requires Thrust Button.
Note: Requires upgraded distributor gear/fuel pump pushrod.
Note: Ignition firing order must be changed to 1-8-7-3-6-5-4-2. |