I was thinking I read some where that you can tap a wire from the PCM to read a/f ratio, is that narrow band?
So if I need a wide band where do you install that o2 sensor? before or after the cat? is it a new senor all together or do you swap out one of the stockers?
Yep on a ranger thats only going to be a narrow band. Only a few cars have wideband in stock form. Mostly european high end stuff.
Never have one downstream of a cat. You can do one of two things. You can unscrew the stock drivers side 02 and wire it up out of the spray of water. Then screw in the wideband.
Or you can actually tap the stock 02 wiring into the wideband. That way the PCM gets all it needs and you can have a full time in-cab wideband.
(A lot of mustang guys do it that way)
Others.. weld in an additional bung.
He who is enslaved to the compass is free to sail the seas
The narrow band rich/lean A/F meter like the Autometer 4375 can piggyback off of the signal wire from either of the factory upsteam sensors. The narrow band gives you a vague idea about what's going on (rich, lean or stoichiometric) but you really need the actual A/F numbers from a wideband to calibrate or monitor the open loop mixture.
A wideband uses a more sophisticated sensor and it should be installed upsteam of the cats so you can use it for both closed and open loop. I changed from the 4375 to the wideband 4378 when I installed the supercharger. I had already added the extra bung to the exhaust when I did the V8 swap.
Since the late model Ranger returnless fuel system runs at about 65~70 PSI, I have the same 4363 FP gauge that you referenced above. Instead of boost only, I installed a 4301 vacuum/boost gauge that reads 30 inHg vac to 20 PSI boost.