AFR gauges are for looks only. Most of them are narrowband and just tell you roughly what the car is doing between rich, stoich, and lean. However, a wideband AEM UEGO will tell you what your exact AFR is down to the 10th - that is useful for tuning.
Needless to say, I have an Autometer AFR gauge narrowband because I think it looks cool.
But then again.. A wideband gauge is only "helpful" if you can tune with it, like with an AEM EMS. A VAFC will still display what the AFR is when it is being tuned I think.

 

well with a wide band gauge you can find out what spots you are running too rich and too lean and then tune your VAFC on those results correct???

 

you can do this with the EMS, not sure if it can be done with a VAFC though!?!

 

I have the AEM UEGO Gauge...it works very well for tuning purposes...but I wouldn't bother using it with a VAFC...the UEGO itself costs more then a VAFC so it just isn't worth it. However, with the EMS, you can run the car off the Wideband...I have mine set to run 16.5:1 AFR durring gentle cruising highway...this way mileage goes up...although I still only get 31-31.5 so not too much more...city is really only up 1-2mpg too so I guess you really cant expect much. But over time it will make a difference and eventually pay for it self.

But yes its good to the .1 so it is a very useful tool in conjunction with the EMS

 

I thought anything over 14.0 air/fuel ratio and our engines will go kabooom!??!

 

Yeah, that seems really lean???

 

For WOT tuning, yes. You really don't want to go above 13.5, and 13.7 is starting to push it. 14.0 wont mean an instant boom but it could cause problems quick.

If you understood how the EMS worked, you'd understand what I'm doing. Basically the EMS has multiple tuneable "squares" you could say. The x-axis is based on RPM and then the y-axis is based on manifold pressure, so basically the harder I get on it the will reduce the vacuum and move to a "higher" spot in the y-axis frame on my tuning graph. Basically, like I said before, under very light throttle cruising around at low rpm (set it to 5000 max) it will see that AFR. Yes it is lean and I'll probably bump it back to 15.5 since I haven't seen benifits of running it that lean as far as mpg, but the car runs fine. Now when I go WOT I run about 13.0-13.2 or so AFR since I'm getting power through advance timing unlike AFC guys

 

Just wanted to say all my parts are for sale, check it out: CLICK HERE

 

Why not keep the exhaust if hoing SC?
Dang you just got that intake too... Shoot me a price for the STB shipped to 98466.

 

How bout the inline pro 2.5L?? Isnt that considered n/a and will be about the same price with all bolt ons? And what is the reliability on uping the liters?