BB is 16/9 with an AF of 2.53
he is also at -11 BB/100 hands over the 1500 i have with him. I'm not sure if that makes this push worse or not.

Also, he usually buys in short and tries to double up. normally his stack isn't this big

PokerStars No-Limit Hold'em, $6 BB (9 handed) from (Format: Bet The Pot)

UTG+1 ($1000.05)
MP1 ($353.80)
MP2 ($296.40)
MP3 ($740.20)
CO ($601.65)
Hero ($646.20)
SB ($667.75)
BB ($656.10)
UTG ($348)

Preflop: Hero is Button with , .
6 folds, Hero raises to $18, 1 fold, BB raises to $42, Hero calls $24.

Flop: ($87) , , (2 players)
BB bets $54, Hero raises to $604.2,

Assuming he never folds you'll still not lose money doing it. If he has AK or an overpair that he's willing to fold, you're definetely +EV here.

Having said that I think you can just flat call the flop instead, you're straight draw will be impossible for him to detect and HU people don't tend to worry too much about the flushes.

I like the fact that numbers wise you're about 2% from 50/50 but that you're gambling 1 stack versus what will feel like a double stack against the villain as he's a normally half stacked.

Does he think you would ever play AA this way though because I'd like a few percentage points extra of fold equity.

I can't see any way that this isn't at worst case neutral EV.

Doesn't harm ones image too