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If you are looking for horsepower out of it start looking into mini me swaps if your on a budget
If not on a budget then look into full motor swaps, because besides swaps or turbo your not going to make much hp on a civic.
Also since its a lx it is a non vtec and one of the less deseriable motors.
A mini me swap would be putting a vtec head from an ex motor onto the bottom block you already have it all depends on what your goals, budget etc are.