I think for 90% of people the are just looking a decent powerplant even if power isn't much of a concern would still be better off with a stock 5.9 Magnum or even the 5.2 version with 4bbl and duals. No one likes a dead car thats why every modern family sedans have a better power to weight ratio than most muscle cars add efi and OD for even better drivablity. And for those that want a bit of performance add cam headers gears and stall. If you got to ask if you should upgrade from a /6 273 or even 318 the answer is probably yes or other wise you'd already be happy and wouldn't of questioned it.
