318 engine differences between CA and 49 state versions

The real killer in my opinion was the timing delay implemented around '73 IIRC. Certainly was on my '75 slant six. OSAC. Just awful in terms of acceleration, especially part throttle.
Early cats were pretty restrictive too. Don't know when Calf cars got them. Good high flow cats didn't really hit the scene until the Mustang 5.0