Don't understand cams

yellow rose said

It would be interesting to see how others think their way through a build.

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FWIW: For me, it all starts with the application. I'm not intending to be critical, but I'm just thinking that the process YR outlined above seems to be drag race oriented (X ET with Y weight = Z HP). There are a lot more apps out there: street and rally (and road race to a lesser extent) dictate considerably wider RPM ranges for good torque, especially with just 3 or 4 gears. For NA carbed engines, that puts a cap on the duration and overlap to avoid dropping the low RPM torque into the toilet, and drives to higher lift to make up for smaller durations, and then higher SCR to help the lower end RPM torque.

If it was drag racing or circle track, then the operating RPM ranges can be smaller and that opens up the the duration you can use for NA carbed.

All this is driven by NA carbed and 3 or 4 speeds. Put in a 6 speed like a modern rally car, and all of a sudden, the need for a wide RPM range diminishes.