Mine's a 69. I'd say that an air scoop is probably not going to help
with more power. The big drawback in the B30 is the manifold and the
cam, and when they start giving grief, the carburetors.
I changed to SUs and reduced my maintenance effort tremendously.
I'm using HIF6s now and am very happy with them.
I suspect that you will eventually have a cam and/or timing gear failure.
If/when you do the optimum timing gears are the steel ones with the NAPA
aluminum gear a close second. I've got the IPD street performance cam
in mine and it is great but they don't make them any more. KGTrimning in
Sweden has a variety of cams. I'm also using the IPD lifter and pushrod
set in mine and they do still have those - be sure they know you need a whole
DOZEN because most folks are running B20s and only need 8.

If it were mine I wouldn't change the classic grille of the 164. But that
is a style issue. Like Matt says, there is plenty of air and warm is better
when the weather is cold - makes the car a lot more driveable.
--
George Downs, The "original" Walrus3, Bartlesville, Oklahoma