hi guys its been a while

im looking for a learned member who knows his shit about electronics and how to make these 02 sims or cel eliminators

i know the rear 02 sensor ranges from 0.1v to 0.9v with a bad or no cat and around 0.5 to 0.7v slightly wavering being the sweet spot to make the ecu think the cats working normally

ive read conflicting over seas info online to use a capacitor a diode OR a capacitor and diode in tandem

what i need is way to make the wild 0.1v to 0.9v swings in volts being sent from the o2 sensor to be stabilized to around 0.5v to 0.7v

having no knowledge in capacitors diodes and such im looking for some guru here to help me solder in the correct whatever to be able to achieve this

reason i need this info is i have installed an aftermarket exhaust and my engine light keeps coming on with catalyst deficiency below threshold , but its just because i now have high flow cats

thanks
NS