cam lobe fundamentals Q

I have a 318 LA that I am putting Magnum heads onto (EQ, "318-b" ones, if it matters)
I am putting a stock, standard, 360 2 barrel cam in along with it. (extremely similar to a COMP 252, minus 0.015" of lift which I will gain back and a lil more with the Mag 1.6 rocker ratio) but the standard 360 cam was 1/2 the price of the COMP, though it did take me a bit more work to find one than it would have for the COMP version.

I know that instead of 0.410" lift with standard LA shaft rockers, (1.5 Rocker ratio) with the Magnum 1.6s I will have 0.437---or something like that--- will duration, overlap, etc increase the same amount as the lift will?

No. The duration, while yes it changes, but is very minimal in comparison to the lift.

Only the lift changes with the increased 1.6 fulcrum. The lifter still comes back to the base circle on the cam at the same point on the degree wheel & everything is the same ex when the lifter starts to rise the valve is opened 1.6 times that lift amt rather than 1.5 times that amt. EDIT yes .410" X 1.067 = (new lift of) .437"

when changing rocker ratios the area under the curve increases. seat timing remains the same, .050 duration may change 1 degree, .200 lobe lift duration increases 5-7 degrees with a 1.5 to 1.6 ratio change. to notice the effects of ratio change camshaft duration must be measured at the valve.

I stand corrected. I thought only the lift(amt) changed(when going from 1.5 to 1.6)

if you could graph it out you'd notice the change. seat timing is fixed but lift increases meaning the valve will travel more in the same length of time. it's interesting to mock up a block-crank-piston and measure different cams at the lobe and then put a head on and measure at the valve with different rockers. once you see the changes you take rocker ratio changing and the effects little more serious. another thing about measuring at the valve is one finds what the true ratio is, and one finds out that "rated" ratios are not accurate.

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if you could graph it out you'd notice the change. seat timing is fixed but lift increases meaning the valve will travel more in the same length of time. it's interesting to mock up a block-crank-piston and measure different cams at the lobe and then put a head on and measure at the valve with different rockers. once you see the changes you take rocker ratio changing and the effects little more serious. another thing about measuring at the valve is one finds what the true ratio is, and one finds out that "rated" ratios are not accurate.

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Cool and thanks; but 1* difference @0.050 isnt really that much; but compared to the orig stock 318 cam, at 0.373 int/0.400 exh and 240* int/0.248* exh, and the fact that I hear constantly that stock OEM LA rockers are rarely accurate at 1.5 (often 1.3X-1.4 RR) going to the stock 360 cam+ the 1.6s should really be a noticable power/torque improvement.
are the Magnums any more true to their listed ratio?