67' Barracuda 273 (Camshaft Results at the Track)

69 cuda

can you briefly explain why my 65 273 dartcharger will rev right up to 7500 without any issues (valve float etc etc ).. doesn't sound like a big cam when idleing. but just revs to the moon. it has just single valve springs .. no dampeners ..
could a stock cam rev that high without breaking something ?
Thanks !