There are limits to how much more power you can get out of the N/A B230 without spending lots of money. It breathes pretty well as it is, so personally I would keep the existing air filter/intake and header/exhaust. Some people will put in an electric fan to replace the viscous fan, but don’t expect a big gain. I believe a hotter cam will give most bang for the buck and effort. The IPD VX cam seems to be recommended in the US, in Europe where I am there are other alternatives as well.

On a budget, but looking for ways to improve performance, I would recommend spending the first dollars on handling. You will get a noticeably sharper handling car with heavier swaybars (IPD or from a turbo model), gas shocks and struts and 15” rims with wider tires. If the bushings are worn I’d do them first of all though.

A more enjoyable interior? There are always the R-sport seat covers (with side support), wooden trim etc. I’d start with gauges though. A big tach to replace the clock, voltmeter and small clock to replace the blanks etc.

Just my opinion.
Good luck!
Erling.
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