20NL: Limp/Caller minraises my overpair on a dry flop. Pop him?

[Genz]

I'm pretty readless about this player. He limped alot but didn't raise yet in about 40 hands. I'm not afraid of a monster here. I'm caring about extraction, so I was wondering if I raise immediately or just flat call. What do you do?

Edit: please tell me your bet and/or raise sizes.

Carlos Poker 0.10/0.20, hand converted by the iPoker Converter at Talking-Poker

saw flop | <font color="#C00000">saw showdown</font>

Button ($36.33)
SB <font color="#C00000">Hero ($21.65)</font>
BB ($10.12)
UTG UTG ($23.22)
UTG+1 ($26.52)
CO ($3.30)

Preflop: Hero is in the SB with K [img]/images/graemlins/club.gif[/img] K [img]/images/graemlins/diamond.gif[/img]
UTG calls 0.20, 3 folds, Hero raises to 0.90, 1 fold, UTG calls 0.80.

Flop (2.20) 8 [img]/images/graemlins/diamond.gif[/img] 9 [img]/images/graemlins/spade.gif[/img] 4 [img]/images/graemlins/spade.gif[/img]
Hero bets 1.60, UTG raises to 3.20, Hero ???