Reply to "Looking for a hyd roller street cam"

There are several specs I use that mimic the Ford street cams such as the Cobra Jet cam, the single pattern Boss cam, the Motorsport A341 cam, and my own "ultra-Boss" spec. There are subtle differences in intake duration, lobe centerlines, and overlap between each one. The spec I like to work with best is this one, based on the M code camshaft:

Based on Ford D0AZ-6250-C
M code i.e. 1970-1971 351 4V
112° ATDC intake lobe mathematic centerline
117° BTDC exhaust lobe mathematic centerline
Duration (and valve timing) specs may vary +/- 2°
But do not alter the lobe centerlines

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276°/286° advertised duration (281° average)
224°/234° duration at 0.050"

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Duration at 0.050” is based on 52° hyd. intensity
Therefore overlap at 0.050” = 0°
Lobe separation angle = 114.5°

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0.328"/0.328" recommended lobe lift (hyd. tappet)
0.567”/0.567” theoretical valve lift (1.73:1 ratio)
0.550”/0.550” factual valve lift (1.70:1 ratio)

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EVO = 80° BBDC
IVO = 26° BTDC
Overlap = 52°
EVC = 26° ATDC
IVC = 70° ABDC

I'm getting ready to step out for a while. I can pick a set of lobes from the Bullet Cams catalog later this evening, there are plenty of good hydraulic roller cam lobes to choose from.