Stock 340 dyno tests?

The popular small block factory stock engines were yanked from their engine bays & dyno tested to see if they actually made the advertised hp. Only one engine did: the 340. In fact it made 20 hp more [ 295 hp ] than the adv 275 hp. All the others made less hp.
The results were published in the Feb 1969 issue of PHR magazine.
Engine, adv hp, measured hp:
Olds 350 W-31, 325, 280
Pontiac 350 HO, 325, 255
Chev 350, 300, 240
Ford 351, 290, 210.

This is what the writer said: "But we didn't look for close to 300 honest hp with no special tuning at all. What was just as remasrkable is that this engine has good mid-range torque & a pretty smooth smooth, flexible bottom end. It's not a lumpy, high strung engine that's hard to drive on the street. And, to top it, the 340 would would rev up to 6500 rpm right now with the hyd lifters without a whisper of valve float or ignition miss......Chrysler engineers have obviously got a beautiful combination of valve & port size, camshaft & carburetion here. The Chrysler 340 is perhaps the best high performance combination in the industry today."