I've been planning for a carburetor upgrade on my '77 B car from the
original single ZS, looking at the information available on the internet and
finally bought the book on power tuning.
The downdraft Weber was looking pretty attractive because of what I have
read about the need to maintain and occasionally rebuild the SU's, but the
power tuning book doesn't even mention the downdraft Weber, and only
mentions the sidedrafts in the context of racing.
There may be a compare and contact between Su and Weber carburetors that I
haven't seen, so any suggestions and/or links would be appreciated.