I would like to go with a 4 speed or 5 speed box but right now that is off the cards for a year or so, I have had a good look around and am thinking I may be able to use a weber 38 DGAS carb and still use the hot cam as it should develop more vacuum compared to the twin 40's.
But if I were to still use the stock cam would the engine still rev to 7500rpm or would the cam not make power that high?

The mikunis as with most dual choke sidedraughts will not have enough vacuum to shift the auto trans. As with the cam you will loose vacuum, why not use a manual box?

Im trying to get my partners car a little more speed, its auto, now has A14 with factory elec dizzy, Rebuilt oval port head but is still sluggish in my opinion. Soon it will have a 32/36 with water choke which should give it a bit more, otherwise i would like to find some twin hitachis for that orig feel.

Well I am almost ready to fit the new cam to the A15, I have shaved the head, ported the intake ports, rebuilt the bottom end, fitted electronis ignition from datrats, fitted a 2 inch exhaust with extractors, fitted competition valve springs and was considering fitting a 54/86 cam with twin mikuni 40's, that was until I started immagining what the car would drive like since it was an auto.
I wouldn't have any power unti about 3500-4000rpm and being an auto I can't bring the revs up and get going like a manual car can.
So my other choice is to use the stock A15 camshaft, use either a 32/36 DGV weber or a 38 DGAV weber, and tune it to the manufacturers specified instructions.
I think this would help with making the car more happy at lower rpm but would it still rev up to 7500-8000rpm with a stock camshaft? the valve springs are rated for competiton use so it would be a shame to waste them on a 5000rpm street motor