the 1.8 isnt a very popular engine for tuning, from what i can tell (some people may say otherwise). you could probably find some under driven pullies, cold or warm air intake, exhaust sytems, and some other basic bolt-on stuff, but short of tearing it down and building internally, i wouldnt expect much out of it all.
if your wanting any real power from the sentra, you need boost (if this engine is even good for it... idk), or one of the larger engine options, like the very popular 2.0l SR20DE, or the newer 2.5l engine that comes in the Sentra SE-R and Altima 2.5s'.
as for suspension, pretty much anything made for the SE-R should bolt up. its all the same body. same goes for body kits, wings, wheels, etc.
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