>> My chambourcin is now at about 17-18 brix with high acid. I didn't
>> measure the acid, but I can sure taste it.

You taste it more if the grapes aren't ripe.

>I may be able to let the grapes hang another 2 weeks, but doubt that is enough. Is chambourcin
>> any good if the grapes aren't fully ripe?

High acid is common with eastern reds. Picking grapes that aren't
fully ripe makes it worse.

vince norris.