Comp Cams  Magnum  Mechanical Flat Tappet Camshafts
InfoVehicle Info Needed
COMP CAMSPART NUMBER: 249-51-247-4

Comp Cams Magnum Mechanical Flat Tappet Camshafts

$30995
ShippingShips on 10/19/2026
Lowest PriceLowest Price Guarantee

Pontiac 265-455ci 8-cyl. 1955-1981
    Magnum 306S Mechanical Flat Tappet Camshaft
    Lift:.555"/.555"
    Duration:306°/306°
    Lobe Separation Angle:110°
    RPM Range:3000-6500

    Rough idle, Pro Street. Needs 10.5:1+ compression and 3500+ stall. Limited street use.
    Operating Range:3000-6500 RPM
    Duration Advertised:306° Intake / 306° Exhaust
    Duration @ .050' Lift:260° Intake / 260° Exhaust
    Valve Lift:.555' Intake / .555' Exhaust
    Lobe Separation Angle:110°

    Pontiac; Super Duty; SD; SD455; HO; 455 HO; Trans-Am; Catalina; Firebird; Formula; 421; 455; 400; 428; 350; 265; 301; 370; 389; 301; 287; 317; 347; Ram Air; Ram Air IV; Ram Air III; Bonneville; Grand Prix; LeMans; Parisienne; Grand Am; Century; Regal;


    Race idle, Pro Street. Needs 10.5:1+ compression and 3500+ stall. Limited street use.

Emissions Note:

This part is only legal for sale and use on Uncontrolled (Non-Emissions Controlled) Vehicles or on vehicles used solely for the purposes of closed competition racing.

CLICK THIS LINK FOR IMPORTANT CARB & EPA EMISSIONS INFORMATION ABOUT THIS PART

Part TypeCamshaft
BrandCOMP CAMS
Package Height2.8
Package Width3.1
Package Length24.3
Weight8.3 PG
Part CategoryPerformance Parts
Exh. Duration @ .050 In. (Deg)260
Cam StyleMechanical flat tappet
Grind Number306S
Exh. Duration Advertised (Deg)306
Engine Make/SizePontiac 265-455
Intake Valve Lift With Factory Rocker Arm Ratio (I0.555
Int. Duration @ .050 In. (Deg)260
Basic Operating Rpm Range3,000-6,500
Intake Valve Lift0.555 in (14.097 mm)
Computer-Controlled CompatibleNo
Int. Duration Advertised (Deg)306
Lobe Separation (Deg)110
Rpm Range3000-6500
Advertised Duration306 int./306 exh.
Exhaust Valve Lift With Factory Rocker Arm Ratio (0.555
UsageStreet/Strip
Valve Lift With Factory Rocker Arm Ratio0.555 int./0.555 exh.
QuantitySold individually
Exhaust Valve Lift0.555 in (14.097 mm)
Advertised Intake Duration306
Intake Duration At 050 Inch Lift260
Exhaust Duration At 050 Inch Lift260
Advertised Exhaust Duration306
Lifter TypeMechanical Flat Tappet
Duration At 050 Inch Lift260 int./260 exh.
Valve Springs RequiredYes
Vendor Part Number51-247-4
Package Qty1
Package TypeEA
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