I've got a 164 that use to have stromburg carbs now it
has SU HS6 carbs. I don't like them. There are flat
spots and it runs lean at WOT and gets much worse fuel
economy than when it had the stromburgs (they were in
okay shape when I replaced them with the SUs). I'm
thinking of swapping the ZS back in since they were in
okay shape to begin with. Or if I can find them I might
want to use HIF6 carbs. I've read that they do indeed
flow more than the HS6 carbs.

If I were to go to a hardcore performance B30, I would
use the stock FI head (with the big valves, maybe a 1975
with hardened valve seats) skimmed to 9.5C/R, a K grind
cam from scandcar.nl for not a whole lot of money, a
stock FI setup (fuel pump, fuel tank, intake manifold,
D-jet injectors / fuel rail) but instead of with the D-jet
control an aftermarket fuel injection control setup
from a company like sdsefi.com. Oh, and either a 1975
distributor or a crank fired ignition (again from the
sdsefi people, or something similar.) Of course, I think
the crank fired ignition is really only useful if you have
a turbo / supercharger..

Depending on the health of the bottom end, I may or may
not go to the 3.3 setup. What is the relative cost of
the pistons? What about the rods / crank? Would it
be possible to use the older non metric crank but with
some snazzy rods that use the B21 wrist pin but have the
older B20 crank size, are lightened, but that don't tend
to snap like the metric B20 rods?
c