[AMC-list] question on this cam grind, specs

[tom jennings <tomj@xxxxxxx>]

So I bought one of Doug Galvin's performance cams for the 195.6 OHV. I asked
for specs (cam card) before I bought, he didn't have any one hand, but one
would come in ythe box; he said it was basically an "RV" cam, more torque at
1000 rpm up at the expense of torque over 3500 rpm, not a bad tradeoff in
this car. Thought I'd take a chance and look at the cam card when it came,
seemed like a safe bet (I can return it unused).

The TSM specs only duration and opening time, which I assume is seat to
seat. The software I use (SCDynoSim) does the math for me, but I hand
checked it and it's correct. The cam card with the new cam specifies lift,
duration etc at .006, .050, .100 lift.

So if I compare stock cam seat-to-seat, vs. .006" lift of the new cam (is
that good enough for ballpark?) I get:

factory: 244 duration (I opens 13 btdc closes 52 abdc;   E opens 55 closes
10) overlap 22 degrees    (SEAT TO SEAT)
new:     348 duration (I opens 64 btdc closes 105 abdc; E opens 105 closes
65) overlap 130 degrees (at .006 LIFT)

Numbers rounded to nearest whole. Lift on the new cam is about .020 higher.

The new cam doesn't seem right for an "RV" cam. All that overlap! That
sounds like it will have no vacuum, and that duration seems pointless at low
speeds, reversion and all that.

Am I nuts or is this a bad cam for a slow turning long stroke motor?
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