Best amount to 4-bet?

[KRANTZ]

10/20 NL, Effective stacks 2000.

You're playing something like 23/16, doing a lot of position raising and being generally aggro. Villain is a good player, 25/17 or so and loves to repop you preflop. You guys have a history of raising each other light, in and out of position.

Folds to you in the SB, and you open raise to $70 with AJs, Villain repops you to $235 knowing you have a wide range. Sometimes you'll call here, sometimes you 4bet. This time you decide to 4bet.

Question 1) If we've decided to 4bet, what's the best amount?

If you make it $1000 and he pushes, you're getting 3:1, which would mean you're correct to call even if his range is AA-KK and AK (28% equity). You estimate his 5 betting range is AA-TT, AQ, AK. Against that range, you've got 30% equity.

Question 2) Knowing what we do, what's the highest EV play after he 3bets you? Meaning, what's the optimal amount to 4-bet to?