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Since I believe the DC/MP Solids all come from the same lobe "family"........

First the advertised duration is incorrect (for what we're all used to)

The seat to seat duration is given @ .015" not .020"

To find duartion @ .020", subtract 8º from what MP tells you.

To find duration @ .050", subtract 32º(intensity)from the answer you got from above.

So, a 296º-.557" is really 288º @ .020"/256º @ .050"

312º-.590.........304º @ .020"/272º @ .050" and so on

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Keep in mind when comparing duration at .050 on a hydraulic verses a solid, or two solids with different lash specs, that the lash must be taken into account. I have found that 1/2 degree per thousanth of lash is a decent rule of thumb.

Most of the solid cams I use have lash specs of .018 in. so I would subtract 9 degrees off the solid cam duration at .050 to compare to a hydraulic (with no lash). The mopar cams the lobes are designed with a .028 lash so I would subtract about 5 degrees at .050 to compare it to solid cam with a .018 lash.

If you want to know the actual valve seat timing you could set the lash and then measure crank degrees from when the valve/retainer first moves off the seat to when it rests on the seat. Or you could divide the lash by the rocker ratio and measure the duration at the lifter with that lift (rocker ratios do not remain constant throughout the lift range but this would be a good rough approximation).

Could do the same thing for effective lifter duration at .050 by measuring duration of valve lift at (.050 x rocker ratio) after setting lash.


Merry Chistmas