Unless government or racing regulations prevent you, swapping in a bigger engine will almost for sure be less expensive for the same power level as a reworked A15. And could easily have more power.

For example, put in a KA24, L18 or Z20, which have all been done. Or any other rear-wheel-drive engine you can get at a good price in your local area.

i never had a 32/36 unfortunately, and the 42mm webers ive got arnt great for a 1200

so i cant really tell you much, up high definate big gains but mine run like crap at low revs so its hard to say

stick with the 32/36 weber & get a mild cam for it.this will give you the best,cheapest immediate result.going to twins without upping the cam won't do much,cause the cam will run out before the carbs.i've had an a15 with a stock carb & a mild cam (can't remember the specs,but it was small) & it revved to 7000 easily.wade cams in melbourne,arthur johnson in sydney,or tighe cams in qld all have a range of reground cams available,so maybe someone in adelaide can help you source one,or just talk to them.try some of the old rally shops,or someone like peter hall,whose name appears in zoom occasionally.

i just got hold of nice rconed 32/36 DGV weber single donwdraught and i am putting on my stock A12 motor on monday .

has anyone run this on a this on thier stock A12, how did it go?

I ran a Weber 32/36 DGAV on my A12. It goes on easy, and wakes the engine up past 5,000 rpm. The only downside is that it always had a bit of off-idle hesitation that I couldn't make go away. Tip: using the stock manifold insert tube helped with off-idle performance.

The Weber DGV has a cable operated mechanical choke i think?, whereas the DGAV has an automatic choke, with both electric and water control types being available i pretty sure.
i dont think this makes much differeence bettween them.

what do mean idle hesitent? what was happening?

(i have an adapter plate for the weber)

By off-idle hesitation I mean that it idled perfectly. It accelerated and cruised perfectly, revved hard to 6,000 rpm ... but giving it just a little throttle, just over idle the engine waited just a little bit before it took off. I tried different idle mixture tubes, pump jets, etc in attempts to get rid of this little problem.

On reflection, I probably should have gotten a book on tuning the Weber carb, but I had good success with tuning the main jets etc ... at the time I assumed it was because the carb was 'big' relative to the engine. That may have been false reasoning.

The tube that helped is the Datsun manifold-to-carb plastic spacer, it has a metal tube insert that extends down into the manifold. With that out there was more hesitation, with it in, it ran better.

That was my experience with the A12 and a 32/36, but others using A14s have been more than pleased with theirs ... I would certainly try it again, as Webers are so plentiful around here. I have two in the garage right now.