3 starring max th9 lvl 1 hounds?

So do you think it's possible to 3 star maxed th9 bases with lvl 1 lavahounds?

It is very unlikely that you would be able to accomplish a 3 star on a max TH9 with only lvl 1 hounds. But yes it can be done, especially if you understand the strategy very well.

I have lvl 2 lava hounds and I can only 3 star mid level TH9s.

Lava loon takes some skill to achieve 3 stars.
Perhaps with a 5th level 2 hound in your castle and
decent heros you could do it.
Can any AD be taken out with your queen before you launch loons?
Are the Xbows ground instead of air?
What level is the opposing queen?

No problem for the hound in the castle, it is lvl 3!
When penta lalooning u have to attack from the side of queen?

It's certainly possible, because I've done it before, back when my hounds were level 1. It mostly depends on the layout of the base, though.

The most important difference between level 1 and level 2 hounds isn't the health, it's the extra lava pups. The 500HP increase will really only make the hounds live about a second longer. The 2 extra pups per hound means 8 extra pups if you use 4 hounds, or 10 if you use 5. Those pups will help a lot with killing the AQ, killing the CC troops if you don't lure, distracting defenses, and with cleanup.

All I can say is upgrade to level 2 asap!!