no responses on model forums…prob same peeps here…can’t find cam specs in archives or anywhere…so, what are as manufactured dimension/specs for the 5/16 and 3/8 camshafts?
I’d like to know the dimensions of back of cam to lobe tip, the circumference of round part (off lobe…side to side)…and what are the duration specs etc. I have measured with caliper (on 5/16) but want to verify against factory mfg spec. Anyone have it? ( in selecting a replacement cam it will be wise to check).Cams changed a bit over the years…interested in all the iterations that could be used in an XK-6cyl but mainly 120-140. Thanks Nick
Contact Dick Maury, at Coventry West: he should have your answers.
…or, Rob Reilly.
Exhaust cam C.5718 from XK140 C head is 1.425" at the peak and 1.040" at 90 degrees to the peak. Subtract .008 for tappet clearance and you get a lift of about .377" or so.
Cam timing angles are given in the XK120 manual page B44. Since XK120 angles are different from Mark VII, and my manual is printing RP1 dating from after Bill became Sir William in 1956, I imagine they are giving the 3/8 lift duration for 120 and the 5/16 lift duration for Mark VII.
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