I have an 89 civic sedan with a d15b2 5 speed with cold air intake and cat-back exaust. I am still pretty new to hondas but i am very mechanically inclined, and i was just wondering what sort of stuff I can do to my motor?? head swaps, tuning, ect anything to get more power. Or in the future what would would be an inexpensive motor swap??

Your options for swapping are huge, I'd look into a B series motor, everyone here like jdmsunrise.com.

could posibly do some headers, intake manifold, and throttle body

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cylinder head guru!

Non Vtec power

for a 4th gen id stay away from the Bs because of their OBD and size. weird conversions. it would be better to get a ZC or JDM D15B.