Kitten size vs. cat size at maturity

Question
My Savannah kitten is 7.3lbs and he won't even be 4 months old for another week.  He is long and lean, and very tall with long back legs.  He's not overweight in the least.

I wonder, is there any way to guess how big he will get?

Answer
I have no idea how big your cat will get. A lot of that has to do with breed, diet and health.

Most cats reach their full growth size-wise by 7-8 months (in males) but they still grow a bit more from the inside.

Sounds like a beautiful cat. Make sure he eats a GOOD diet, not a grocery store diet.