1g o2 sensor in 2g housing - good or bad?

[yotabeater]

i've been battling a helluva knock problem with my 91 tsi. running a b16g, 550's, 255 pump, 19 psi, afpr, afc, datalogger, blah blah. i thought my o2 sensor was bad, and my buddy had a spare off his car, so we tried switching it out. took mine out, and forgot i had a 2g o2 housing. the ends of the sensors were completely different.

the 2g was really girthy, with about 15 holes in it for measuring. the 1g sensor was about half as big, and only 4 holes. the threads were the same, so we slapped it in and started tuning. the car ran freakin smooth as hell, and got rid of a lot of my part-throttle knock.

my question, is there any downside to this? do i have to run a 2g sensor in a 2g housing? i had to richen up my settings hella after i put the sensor in. hi's are at -4% from 4k-7k, lows are about -11% all across, except for 1k, which is weirdly at +10% (seems really rich), but my o2 volts never go above .89 at WOT, no matter how much i richen it. also, i am running the mmcd logging software. when the long term fuel trims are above 100%, is that rich or lean? me and my friend keep arguing about it. any feedback is appreciated as i am fairly new to tuning. thanks.

 

[evotuner]

I am running a 2G o2 housing with a 1G o2 sensor, and haven't experienced any problems.

 

[yotabeater]

what about my afc settings and o2 volts? even with how rich it is, i get like 18 counts of knock doing 4th and 5th gear pulls at WOT. :thumbdown