Read a post once.. think it was from Panic.. that the retricted intake was for low end torque purposes to help get the heavy weight servi off the line. Before I had read that.. I too also opened up my intake on a 67 using a Delorto carb to 1" .. and it did affect the off the line lower end torque/power but the swap was I had higher revs, more top end power, and speed. Building a stripped 49 bobber trike now, and almost done.. am thinking of running a wl intake with a Mikuni to see what happens. Will get back with that info when I get it up and running.
When they're running you out of town.. get out in front and make it look like a parade.