Reply to "Seeking stock cam specs, 1972 Pantera"

• D2ZZ-6250-B
• Engine Code Q
• 270°/290° duration at 0.006
• 205°/220° duration at 0.050
• 0.481/0.490 gross valve lift
• 46° overlap
• 117° LSA
• Timing: the camshaft is indexed 4° retarded,
ICL = 121° ATDC, IVC = 76° ABDC

Aftermarket versions of the camshaft are available from several companies including Sealed Power (p.n. CS-650) which is available via Summit Racing. The aftermarket versions differ in having 115° LSA and therefore 50° overlap. The aftermarket cams are indexed 4° retarded same as the factory cam; ICL = 119° ATDC, IVC = 74° ABDC.

Engines equipped with Cobra Jet camshafts should have the camshaft timing advanced by nominally 4°. This will set the intake lobe centerline of a factory cam at 117° ATDC, and the intake lobe centerline of an aftermarket version at 115° ATDC. The seated intake valve closing also advances to 72° ABDC for the factory cam and 70° ABDC for the aftermarket version.

To advance a camshaft or accurately time any camshaft requires a camshaft timing set with a 9 keyway crank sprocket. The timing set should also feature a steel cam sprocket and a chain manufactured by Renolds or JWIS; do not install a timing set using Rolon chain. Three possible candidates include Cloyes p.n. 9-3621X9 ($147 USD), Ford Racing p.n. M-6268-A351 ($166 USD), or Rollmaster p.n. CS3091. The premium Rollmaster sets which were formerly called the red series are now referred to as the gold series.

Some cam sprockets lack the raised center needed for a two-piece (inner/outer) fuel pump eccentric. If you run into this problem there is a simple remedy. Install a washer of the appropriate diameter that is about 0.050 inch thick between the inner (stationary) eccentric and the cam sprocket, something like a fender washer will do the trick.