sohcvtecowns

hey ppl ....ive been having problems with my car lately and ive decide to change the engine ... but the thing is that theres to many engines to choose from ...i think i want to stay in the sohc engines maybe a ls or zc dohc but i cant decide im tight on money and cant aford a sir and candt really wait cuz i need my car to get to work and back ....i have the d15b7 lx which is pretty slow .....please help me if u have and way of help me by maybe give some strong points about some affordable engines ...thx