Mopar Performance Purple Mechanical Camshaft - P4120653AE Cam Card

>I have seen hydraulic rollers with ramps from "advertised to .050s", of between 53degrees and to over 80 degrees, per pair (opening plus closing).
In the Comp case above, you are looking at 274 less 224=50*@.050....... but at the advertised, the valves are still stated to be, .006 open! So you gotta watch those specs like a hawk!
I think this is an unfair practice, but what do I know. Why? Because you think you are buying a 274/282/110, but if the valves are not yet closed, then what are you actually getting? This cam may act like a 274/282/110 after 3000rpm, but what if the intake valve doesn't close for another 8 or 12 or 16 flipping degrees.... This is how you get unhappy streeters. They think they are buying a 224 at .050, but not all [email protected] are equals.
My guess is that the ramps are very very slow, from .006 to on the seat and not leaking. Lets say the opening ramp is another 10* long; a conservative number, that would make the Ica, at plus 4 degrees advanced, to be 73* ; which is pretty late.
With a 73* Ica, the Wallace predicts 153psi CCP, and a VP of just 112; which will make the engine feel like a 318LA at under 3000/3400 rpm; so you will need a bit of a stall to get past that.
Sooooooo, if you want to run this 274 cam, 153psi leaves plenty of room for improvement in the Scr.
Butum if the ramps are longer, well it will just be more doggie.

Now:
Swapping to a solid-roller lifter will cure that , but now you have a different problem; namely, with the same .050 numbers, your intake valve may close too early and very likely your pressure will be too high.
For solid rollers, I have seen numbers from Zero-lash to .050 of as little a 39 degrees. If you happen to get one of those, then the [email protected] becomes 263 at zero-lash, so if a 110 cam installed at 106, then the Ica becomes 57.5, and the Wallace predicts over 180psi with a now very healthy VP of 153.....
But you cannot run 180psi with iron heads, on pump gas at WOT.
That will take alloy heads.

So now, with a solid roller, and iron heads, you are sorta forced (at 10.5Scr) to go bigger on the .050 to get the intake valves actually closed on the seats, a lil LATER.