A few things:

1. You say you're not telling what the villain did, but including the final pot size kind of gives it away.

2. I make this play all the time, and I don't like it. I think the key is to look at the logic backwards. On the river, your only shot to win is by bluffing, so a bluff is probably correct. That means when you bet on the turn, you're really committing two bets to the pot, not one. So in a sense, you're only getting 3.5:2 odds on your bluff (counting the opponent's turn call). Is that really good enough here?

3. I agree that reads would make this decision much easier. I'm kind of coming to the conclusion that without reads, I like this a lot better when I'm in position than when I'm out of position.