1/2 - limp crap from SB, surprising flop

I likes limping suited junk SB :D

BB is ubernit, here I had him at 6/2, over a small sample tho. Until now he was willing to felt every hand he decided to play. No reads on MP2. I was pretty sure BB had to have a 4 or 33, MP2 has probably some crap like 77. Do I better slowplay,try to keep the pot small and maybe let MP2 donate a few chips or do we aim to felt this?
Its a limped pot, meaning BB could have any 4, 6 ahead of us (counting 33, discounting 44), 6 are dead.

$1/$2 No Limit Holdem
10 players
Converted at weaktight.com

Stacks:
UTG ($109.00)
UTG+1 ($63.30)
UTG+2 ($318.54)
MP1 ($79.70)
MP2 ($97.00)
MP3 ($95.16)
CO ($489.07)
BTN ($289.95)
Hero ($236.05)
BB ($196.15)

Pre-flop: ($3, 10 players) Hero is SB :4h: :th:
3 folds, MP1 calls $2, MP2 calls $2, 3 folds, Hero calls $1, BB checks

Flop: :4c: :4s: :3h: ($8, 4 players)
Hero checks, BB bets $4, 1 fold, MP2 raises to $9, $9 to Hero ($234.05)?

be careful. he wont felt an overpair and he could have A4s or the boat

My first thought was raise, but that pretty much nails us for having at least a 4 or better, right?... I think with the odd situation that we should make it $30ish... maybe even more.. But I'm probably stupid.

Does anyone else like betting out on the flop?

i usually lead.

usually I lead this too, but then I remembered the part in ToP where Sklansky says "be more apt to slowplay 2nd nuts"

with no reads on mp2 and BB being quite nitty/but aggressive in pots he is playing, you could flat call fully expecting BB to push over. I don't know if your call will scare him enough to slow him down though. That way mp2 can commit himself and you have a bit more padding in the pot to soften the blows those times BB has you crushed.

mp2 probably has something like a weak overpair here. If he has the 4, its either going to be with the A (because people love aces) or a 3, 5, 6 (maybe 7) type of kicker. I doubt he would fold any 4, but if there was ever a line that would get a weaker 4 than yours to fold, it would be a check-raise after this action.

I usually felt this but that is a weakness of mine. I will assume that BB will not do something silly like fold J4/Q4 here, so the only plays would seem to be get his stack in without scaring him off, and fold. Like I said, I can't fold this hand. But then again I am not that good.

I lead out. Fold pre, as played $36 to go.

I don't mind the check on the flop as it often induces bluffs because of the paired board, plus we have tripsssssssss!

As played, I definitely raise here. Calling tells our opponents we have a 4 and it also doesn't put pressure on them. If they have a small overpair or 56 or 67 or 52, they have outs but will probably not bet at it again anyways when we call this raise on the flop.

My point is that if we call we won't gain anymore value out of weaker hands, but we might if we raise. Raising also eliminates outs for villains. My only concern here are bigger hands, so lets find out asap. I don't mind folding trips with a ten kicker in a limped pot if it's 4 bet big back at us.