I'm just wonderin what the biggest conversion i can do for my d15b2 i want the most horsepower i can get I have a 90 honda civic dx sedan

 

well the best swap possible is doing a k24/20a swap. meaning a new accord 2.4 liter block and a rsx k20a vtec head ecu and 6 speed tranny, or a 07 civic si tranny with factory lsd. price- between 4 and 10,000

but on a budget a d16z6 swap or a b18b swap are the 2 cheapest and easiest swaps. and they will give you more power and torque. but either of these will run you between 500 -1500 for everything provided you do your own work