It was suggested to me that the best replacement carb for a standard 120Y (A12) engine is the Hitachi DCG306 - best throttle response, best fuel economy, best fit - if I generally stay under 5,000 RPM. Over 5,000 RPM, the Weber is superior.

Just wanting to hear some more opinions on the topic. Thanks for chiming in!

if the motor is stock and used as a daily nothing beats a the stock carby for throttle response

I have a stock factory pre pollution A12 carb combined with A10 carb and can rev easily over 5000rpm on the A12. They are a perfect carb but if you want more the weber must be matched with slightly better cam to gx specs, ignition, headers and 28/36 not 32/36. The 28 suits our capacity motors from 1000-1600cc better if its a stock to mild engine, great economy good air velocity down low and a nice oomph up top.

Ive had heaps of situations with other datsun 1000 freaks (one oned 20 plus the other more than 50 he used to buy and do up for uni kids nearby) in the past and even some recent ones with Wurzel coming back from a cruise (wurzel but I suspect he has a vanette camshaft!) where my slightly upgraded A12 munchs their A12/A14 and A15 with the same mods or better supposedly powerful mods. I am only 80kg having maybe a 10kg advantage to my other b10 freaks but Nissan engineers did very well with their carb choices. Once you play outside the factory or gx specs its a hard balancing act only turf for the very best in the business.

Guyster if you are leaving the rest stock, stay stock carb - years of trouble free, economic and smooth motoring VS your Nova which Im sure is hot, angry and perky. Stock and Hot - of both worlds.