Need Help O2 & Fuel Trim

[chop91vr4]

I am trying to tune this thing still I have a data logger a A/F guage that doesn't really tell anything other then rich lean & stotic but I have a better infofrom my TB Timer on the O2 voltage & the A/F & I'm trying to figure out how I get the trim percentage from this. I mean wtf is 100% what mathmatical equation do I need to do to come up with this?>? Thanks I apperciate any help with this

 

[tektic]

What are you logging and tuning with?
You cant tune with a narrow band o2 sensor.

 

[chop91vr4]

I have a pda logger & I'm about 98% positive that it has a wideband in it, but that is from the fact that I removed it when I put new down pipe on. ( from knowing what they both look like this was a wideband )

 

[prove_it]

100% Is basically your centerline for the fuel trim. Anything below 100% and the ecm is pulling fuel, anything over 100% and the ecm is adding fuel to the mix.

Please correct me if I'm wrong, I MAY be backwards as it's been a while since dealing with this old school tuning.

You'll see it won't stay at 100, it will vary 95-105 at idle. Also in WOT the fuel trims are not used. (open loop)