Dear Aspirant, 

Eamcet rank is calculated taking Wightages from both eamcet score and inter result. So with 43 score in eamcet and also 860 in boards your eamcet rank may be around 80,000 - 90,000.

For accurate rank status, use the rank predictor tool. Here is the link for it :

https://www.google.com/url?sa=t&source=web&rct=j&url=https://engineering.careers360.com/tags/rank-predictor&ved=2ahUKEwisiqahuozjAhXJRY8KHYhLAUEQFjAHegQIBRAB&usg=AOvVaw0fPCt9iffbBM0w314yEMEe

Hope this helps. 

Good luck.