You're correct, nitrous is only on when you hit the button. It should ideally only be used at wide open throttle, above 2500 rpm or so. A universal EFI kit can be installed on virtually any engine, for about $500. Nitrous refills cost about $3-4 per lb., depending on local prices. You should retard the timing 1 degree for every 25 h.p. of nitrous. Start with the smallest setting, and work upward slowly. Make sure your fuel system and ignition are in good condition.
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Virtual Speed
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