Did the 340 really make 275hp?

I always wondered how they could rate a 327 @ 375 H.P. and then rate the '70 340 @ 275 H.P......or at least not rate it @ 1 H.P. per cube. The 340 on paper looks more impressive compared to those older chevy motors, and the chevy motors definitely didn't have any great looking exhaust manifolding either. Interesting.....but I also think the proof is in the quarter-mile times too. Maybe 340's have a flatter torque curve.