The O2 simms for the JTEC powered Vipers [ pre GenIV ] won't work. To my knowledge nobody makes truly functional O2 simms for an NGC equipped Viper. You can *try* some of the tricks the LX/LC guys use like the anti-foulers and "mini-cats" which aren't 100% reliable or you can do the Performance PCM and eliminate the problem and get some bonuses as well in other areas.