IMO, 50k - 75k. I just haven't done so yet. IDK why, guess I was gonna keep em in til 100k. The Maggie goin on in summer may make me change my mind. But even as it sits N/A at 82k & counting, I'd be pissed if I replace em & the MPG improves tremendously & it performs like a beast.

In a way, I'm kinda hoping it does.

Only reason I wouldn't want it to see both goals, is cause then I'll kick myself for not havin done it sooner.

 

You won't see a performance increase by changing the O2s. All of the real power comes from open loop which doesn't include data from the O2s. You could see an increase in cruising fuel economy. You could also see a decrease. It just depends if the O2s are skewing the oxygen level that they are reading.

 

Gotcha.

No decrease. My winter MPG is in the toilet.

I plan to hook up a W/B in prep of the Maggie. As it sits, I have no clue on A/F, unless I go to dyno or hook up HPT. I figured I'd have my Maggie on long ago, so I didn't want a lite show so I held off on W/B install.

I think my A/F is outta whack anyway. It was tuned post cam. After tune, my cat material degraded / burned up / blew apart in chunks. It flows better now...
Not part of my original plan, just sayin.

 

Log your O2 activity, if they're workin fine, let em ride. Don't know who told you the 30K thing Tom, but it sounds like an O2 sensor salesman to me BTW, rock auto dot com has Denso factory replacements at a great price, I replaced both of mine last May when my B1S1 took a dump

 

It's not hard to switch rears to front. If you look on the plastic connector it has a letter by each wire (A, B, C, D). Just coordinate this onto the rear connector.

 

thanks for the help guys