3.27 ratio in slow traffic

[Great Lakes Greg]

I have a lighter weight body style with a fresh build B engine. I have no doubt that a 3.27 gear would work well on the open road for me, but question its practicality on tour with "regular" cars. 80% of my driving is in groups that travel 40 m.p.h. I see this scenario causing a lot of lugging of the engine, especially on grades. Is the jump from the 3.78 that drastic, or am I making something out of nothing? Thanks fellers.