The pH of varieties that have been tested is in a very narrow range and off hand I can't think of any large ones that I feel have an agressive taste, which is probably closest to what you call acidic.

Some smaller ones that have an aggresive taste to me might include;

Sandpoint
Silvery For Tree
Tigerella, the original one, small red with gold jagged stripes
Noire des Cosebeauf, not really small
Purple Calabash, not really small

...... to name a few, but taste is personal and perceptual so I know there are some who think the tastes of those I listed is just great. LOL

Whatever. ( smile)

Carolyn

Red Mortgage Lifter is close, but flavor is not as intense as you might like. I harvested some 3 pounders this summer. The best overall intense flavored slicer I grow is probably Druzba.

DarJones

Giant Belgium is large and has a very nice strong Tomato flavor. I'm not sure of the acidity, but so far I would rate it very highly. It has the most zing of the ones I am growing this year, including Cherokee Purple, Italian Heirloom, Dagma's Perfection and Chocolate Stripes. GB is on the pinkish side though. I have heard others describe it as similar in taste to Brandywine, but bigger and a little easier to grow.

CH

I did Parks Whoopers, but they got small after the 5th picking. So next year I am going to plant some late plants.
Do not have a high acid tomato, but will try a few of the ones listed above.

Well, since you capitalized "Big", I'll throw out a couple ideas for you.

I think Pruden's Purple would be a superior tasting and generally larger tomato than Park's Whopper. The key would be to pick it just as it becomes pink, and you will find it to be a firm, delicious tomato with a great zing.

The other one I can think of would be Russian #117. While it is heart shaped (although the shapes are highly variable when I grow it), once you slice it, you still get big round slices. It is a very firm, solid, tomato, with great taste, and it is certainly Big, with some fruit going into Very Big territory.

I don't think either of them would be what somebody would call High Acid from a technical standpoint, but they sure as heck are delicious tomatoes that are also large and prolific.

The "Delicious" is the current record holder at over 7 pounds . Try that

Thanks to all.

I don't need a 7 pounder Dickiefickle but it does sound intriguing! LOL I might try them next year. I googled and bookmarked!

Try Red Penna if you like that old time acidy taste, it's about 14-20oz.