Overdrive or don't worry about it? !

I'm all about 323s they're beautiful highway gear that's why they was a standard gear in roadrunners 340 swingers super bees cudas etc and as mentioned by 318 willrun with all the additional torque of a 4-in crank bottom end will be no problem. The 323 were used when the speed limit was 70 miles an hour very similar to what people are going today. And a little bigger tire if you even want more.of course camming will be a consideration also I didn't see that mentioned in the previous post.