I can tell you it would cause your FI system to use the limp home mode for mixture. You would also get a check engine light. The sensor is there to ensure that the ecu commands correct amount of fuel for the charge air parameters. If you have mods that produce better/more airflow and require additonal fuel then you need an aftermarket FI system after a certain hp point. Even these systems utilize an 02 sensor. I've read that systems such as the K-jet 3.1 in my 240 can only handle 160hp. The system you have can only accomodate so much change in fuel/air mix. So I would say that removing it would only create poorer performance and everyone knows that a na 240 needs all the help it can get. Try a cold air intake, cam, modified head, headers.
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92 244 lowered, Bilsteins, IPD sways, Unitek cam/header, TSW Revo 18x8's - 94 965 Niiice MONEY PIT! - 76 Datsun 280Z lowered, modified head, cam, headers, intake