"Together with the Holbay camshaft and the correct Webers and right air
filter (look up! the carb set-up is very sensitive to the air filter) you
get a torque engine. Its not a high RPM engine! This suits the 3.77 rear
end with overdrive gearbox."
I do not think this is 100% accurate. In general, if you take two
identical sized engines and try to increase power to one of them by better
breathing and carberation, that brings on power at the higher rpms at the
expense of the lower rpms. On the other hand, if you take otherwise
identical engines and increase the size of one of the engines, you will
gain that power and torque at the lower rpms. So, by going the Holbay
route, you generally lose torque and power at the lower ends.