Reply to "Questions regarding George's 275/285 Custom Street Cam Profile"

Here's the first cam spec. I'm using the same lobes as mentioned previously, I couldn't find any better. There's a very limited amount of solid roller street lobes to choose from. Look the spec over, as you'll see I've just moved things around a bit. There's more overlap, and the overlap event is not quite centered on top dead center, the intake valve is opening sooner, exposing the intake system to more piston motion, making the engine lope at idle as you prefer. Or at least that's the plan.

Application: Ford 351 Cleveland solid roller tappet street cam
Grinder: Comp Cams
Lobes:
High Energy Street Roller
Intake #1474
Exhaust #1476
107° ATDC intake lobe mathematic centerline
114° BTDC exhaust lobe mathematic centerline

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280°/288° advertised duration (284° average)
236°/244° duration at 0.050"

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0.3666"/0.3666" lobe lift
0.020”/0.020” lash
0.634”/0.634” theoretical valve lift (1.73:1 ratio)
0.614”/0.614” net valve lift [(lobe lift x 1.730) – lash]
0.603”/0.603” factual valve lift [(lobe lift x 1.70) – lash]

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Indicators
44°/44° intensity (advertised duration – duration at 0.050)
35° major intensity claimed by Comp Cams
Overlap at 0.050” = 19°
Lobe separation angle = 110.5°

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EVO = 78° BBDC
IVO = 33° BTDC
Overlap = 63°
EVC = 30° ATDC
IVC = 67° ABDC