O2 ?

[Bruce Fulper]

Originally Posted by Timetraveler

Rod your O2 needs back pressure to work. I don't believe in using an O2 gauge to dial your car but it can save your engine if your going lean at high rpm. Do your testing with a long extension or a muffler and get your reading. Then run your extensions with a paint stripe and cut at the end of the paint burn. 'OLD SCHOOL'

Does NOT work. Never did. You can cut your way all of the way to the cylinder head. Air changes. Not a reliable test. Leave it where it's at. You're making your own relationship to any changes anyway.