esteem would be better than conti as contis would be heavy. Gonna be a bit expensive job and I doubt if any would do it right at Tvm.
Modding the original engine would be a better choice. Santro/City engines would be costly and feasibility can be a problem. Conti engine should be easy to source ( even the Amby 1800Isz engine is the same ) and cheaper for mods.
If you are successful then you can be the drift king
