A stock carb setup for stock A series is quite formidable as well
there are plenty of ways to make the stock carbed A series very
smooth with little tricks like indexing spark plugs and my fave
a heavier flywheel than stock increases economy and driveability
in all street rpm ranges. Electronic ignition and once is a while
spray h20 into a warmed up running engine to clear carbon deposits

As an experiment after owning a 2cv used a custom billet flywheel
made for speedway! that came with some parts I bought in a lot
and fitted to an high comp stock A12 you couldnt stall it
and climbed hills like it was an L series.
It was like a momentum energy storage device!
Few credit how silky smooth driving is with a heavier fly

The EFI manis for the A series flow more than the stock carb manis
and rowland manifolds make a nice setup for 38/38 as well and
Ive seen an SU adaptor to a similar manifold to suit 2 inch SU
which could flow more than stock and match efi hp ratings