Question for Mike 76251
 

What sensor do you use for the air/fuel ratio, and where is the temp sensor for your tranny temp?

Not the Mike, but a Mike never the less. :)

I had a AF meter in my truck at one time. Thought it was something I couldn't live without. The Autometer one no doubt. Trouble is, I still have my EGR and all emissions stuff hooked up and working. The EGR and AIR pump play havoc with the AF meter, deluting the exhaust mixture so my gauge bounced around something terrible. So I pulled it out and sold it to someone who doesn't have emissions crap on their truck, and could actually get some use out of it.

But, to get to the point. The AF ratio meter uses a O2 sensor in the exhaust , just like it would for a computer controlled vehicle, except all it's doing is sending signals back to the meter as to what it is seeing, rich or lean, or the best stowick (sp?) This is right in the middle where it should run at normal cruising.

I bought a kit from Autometer for this, which is the wiring harness and O2 sensor. Not cheap for sure. Costs way more than the gauge. I guess the reason is because it's a heated type or something like that.

i believe its STOICH, short for "stoichiometric" i do believe.

Thanks for the reply. Though that would be good for carb tuning but I'm getting better mileage now than I expected. (13 highway)

Is there a tranny temp sensor that I wouldn't have to cut a hole in the oil pan for?

I used a Bosch one wire (non-heated) O2 sensor and mounted it aft of the header collector with a metric weld bung (18?) I got at a bolt and screw place.
The tranny temp sensor came with the guage and mounts in a remote oil filter housing on my fender well. You can see the temp fitting between the two stainless lines coming out of the filter mount,

This isn't on my truck, but is on my 69 Cutlass. I have both tha A/F and the transmission temp.

The A/F is the Autometer Phantom one. Spendy, but I have all Phantom gauges so I wanted it to match.

I placed the sensor at the very end of the header collector. If I had it to do over again, I would probably move it a bit closer to the primary tubes. Even though I have a heated O2 sensor, it seems like at idle it cools off enough not to read after a while.

The meter is nice, but not necessary if you don't plan on changing things a lot. If you have a nice digital multimeter, you can do this with a cheap O2 sensor (one wire). Weld the bung in the exhaust and put in the sensor. Run the wire up into the car and then hook it to your voltmeter and run the car. With a non heated sensor, it will take a while, but soon you will see your voltmeter move.

The O2 sensor only puts out something like 1 volt max. But there is a chart somewhere that tells you what the voltages mean as far as lean or rich or stoich. If someone wants to go this route, let me know and I will scrounge up those documents. Once you get the carb and timing tuned, you can remove the O2 sensor and everything is clean again. Or leave it in and just hang the wire under the truck somewhere in case you want to use it for future use.

Since I am always adjusting mixture, timing, heads, etc, etc, I decided to go with the gauge just so I always have it. Makes a great conversation piece as well! :)

Oh yea, the transmission temp. I have a TH350 on my Cutlass. There was a small plug on the passenger side of the transmission. I took the plug out and found oil behind it. And just so happens that the sending unit was the same size so I screwed the sending unit in there and it works great. No drilling or tapping of the pan needed.

Please tell me that's not a Fram oil filter :eek:

Is measuring the temperature there at the filter as accurate as it should be? When the fluid is travelling through the lines on the way to the filter Im sure it cools down some from wind hitting the line.

Everyone else with tranny temp, where did you install the sending unit? On the tranny itself or in the pan?
Just curious as its something I would do if I put in automatic in.

I would put the transmission sending unit in the transmission pan.

I'm doing that A/F Ratio mod today! I'm getting an "Anti-Fouling Plug Adapter" from Kragens for $4, and having it welded in JUST after the header collector. Although I'm not hooking up an A/F Ratio Meter, I am having my friend who has a WideBand O² Sensor, hook it up and we're going to tune the carb to be Stoich @ idle/cruise/WOT. :D
It's nice to have friends with such expensive toys :D
BTW: On that Tranny temp sender, I personally would put it in the pan.

I used a mechanical tranny temp gauge and installed it in the pan. I'm guessing this location is a true indication of fluid temps. I would also guess, if it's installed in the cooler out line, it would be the best indication of fluid temps. This would probably be the highest temps the fluid would see.

But, with this mechanical gauge, I see no way of putting it in the line, or any place else for that matter. The bulb (sensor) on the end of the tube is big, about 2" long. No other way I could see but to put it in the pan.

Works for me anyway.

Oh, and Tim, no way to have it stoich at idle, cruise, and WOT. It ain't going to happen. Where you are concerned about is idle/cruise, mostly cruise. A good idle isn't hard to obtain.

WOT, forget about stoich. It will be full rich.

Fram HP-1 Racing Filter avalible at Autozone, Kragen,Advance, and Walmart.

I was die hard Fram guy as well till I read this. http://www.frankhunt.com/FRANK/corve...lterstudy.html

Thanks Brandon,
Good reading indeed!!

Gotta hook in the printer for those pages!

Mike