[snip]

This has been an interesting discussion, especially if the original engine
was carbureted.  Honda used a three barrel carburetor.  The auxiliary barrel
fed a small quantity of a rich mixture to the CVCC valves.  This mixture was
then ignited in the precombustion chamber eliciting a flame front which then
ignited a lean mixture that was fed to the cylinders through the primary and
secondary barrels (the latter typically only invoked under heavy throttle
such as when the car is under acceleration).  By using this method, Honda
was able to postpone using catalytic converters for many years since it
allowed their engines to be both fuel efficient and have low emissions (yes
I know that the '86 has a cat, this started in '84 which was about 4 or more
years after most other US cars had cats).

Does the Weber carburetor you installed have a separate barrel for the
auxiliary valves?  Or, did you switch over to a head that was for the fuel
injected setup, e.g., '86 Si?  If I remember correctly, the spark plug
electrode on the carbureted units was in the precombustion chamber, not the
main combustion chamber.  If the Weber does not correctly feed the auxiliary
valves, then it might seem that fuel mixture ignition would not occur as
well as originally designed and the car might not pass an emissions
inspection.

Of course, the whole above discussion is mute if indeed the engine had the
fuel injected head which did not have the CVCC valves.

Eric