I need schooling - old vs. new engines

DionR said

I would be curious to hear what your cam specs are. If you get a chance to look them up.

I did do some digging on the Comp website and the biggest cam I could find for a non-VVT Hemi was a Stage 3 cam with 277/284 advertised duration, 224/234 duration at 0.050 lift, 0.632/0.619 lift and a 115 LSA.

But you can't be making 650+ hp with that cam can you? Seems like a pretty small cam to me. That's smaller than the 380hp crate motor cam, duration wise.

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Cam duration/overlap has a much more pronounced effect on the new Hemis than older wedge engines since the valves and ports are so much bigger and the heads are true cross-flow design. At least that's my understanding from seeing other people's builds and the power/torque curves they make.

Like some mentioned before, the engineers designing these newer engines needed to keep the valve timing pretty tame with minimal overlap and wide LSA for emissions and velvet-smooth idle (NVH). So to increase power they massively increased the airflow potential of the heads. Now with those massive-flowing heads you don't need nearly as much valve timing overlap when upgrading the cam, small increases make a bigger difference in power. I read from some guys modding modern Challengers that biggest "Stage 3" cam from Comp kills quite a bit of low-end torque and isn't a good choice for a street car without supporting mods (gearing + weight reduction). Even though the cam specs seem "small" on paper relative to what we're used to dealing with for our old-school V8s.

IIRC from reading old tech literature it was a similar case for BB wedge vs. G2 Hemi cams back in the day. You could physically swap cams between the 2 but the profiles were optimized for each head type and worked best in their respective engines.