Evil Aviator

Yes, but you seem to have missed this passage:

"O2 Target Idle Volt - The target voltage for idle conditions. Some engines require slightly richer mixtures when at idle to ensure a stable idle speed. This can be achieved by setting a slightly higher target voltage for idle conditions."

Add to this the fact that you know darn well that stoich isn't going to give you your best fuel economy at cruise, regardless of what somebody wrote in the manual.

I have a high-flow cat and test pipe that are part of a special quick-change V-band system.

BDC

Go Haltech. It works, very well supported, and has a long history of working on the rotary, particularly the 13B in the Rx7's.

I can help you install it and get it going.

B

Maxthe7man

Yes the 3 way cat needs the stoich flick over to work right..
But if you examine close loop strategy , you will notice that it is indeed functioning for fuel economy at times, such as idle.. If you even tried to program in open loop the average overall leaness a properly tuned closed loop system sees, you would have so many lean spots misfires and surges through the gears, the car would not be very driveable..
I do strange things for fun sometimes, like monitor the ecu's in not only my cars, with both stock and aftermarket ecu's, but also my work truck which is obdII, I learned alot about closed loop by driving with a voltmeter plugged into each vehicle for sometimes, weeks at a time...
Some people will argue that they have seen static a/f's of upward to 18:1's without the stoich flick over of closed loop on a wideband o2 sniff of a tail pipe of some newer cars, while that is true they have not seen it, its not true that its not seeing a flickover, the snapshot averageing sampling of the wideband o2 sensors don't show the stoich flickover...Newer vehicles that are running very lean, with wideband o2 sensors from the factory, are still running closed loop, just a wider range of deviation from stoich is now used, they still flick back and forth, and some cars like the mitsubishs with DFI will take a leaner swing without a misfire due to improved combustion strategy, but they still swing to rich during closed loop operation, on a wideband test the dfi system will show up as a about a 16.5:1 average but is in fact punching back and forth from 12-18:1...
As I mentioned in my post, running overall lean is hard on a motor,there is a reason, we left carbureation back about 20 years ago, if economy was as easy leaning the charge straight out, the carb was ca[able of that wihout 25 lbs of sensors and wiring, closed loop operation seems to keep the exhaust valves from burning up as well, by periodically showing the parts a blip of cooler exhaust gases.
The new obd systems of closed loop, also use oxygen sensor feedback to maintain driveability and fuel economy as the engine wears and the sensors get older, gm's computer will learn each engine individually, and trim the base maps to not only each engine, but each cylinder, it will optimize efficiency of each cylinder over a period of time, so that the as long as everything is working, the vehicle will run a long time while providing the best fuel economy, lowest emmissions and best driveability it can... To say its not closed loop is designed only for emissions is simply not true, its like saying a foot is only designed for standing and then ignoring the fact that it some of it is designed for running and walking..
I can see the difference from the sensor feedback in my gm vehicle, when the computer is reset , the fuel economy dropps by about 3 mpg for around a 1000 km's, then it starts to creep back up, as the computer starts to trim the fuel back to what the engine needs..
The only time I would recommmend and autometer air fuel guage to some one, is when they are tuning a closed loop car , it will show closed loop operation where the wideband will not, I tune with both, and sometimes I use a high quality digitial voltmeter to see what the ecu is doing, on my Gm van, my voltmeter of course bounced back and forth everywhere, however my voltmeter is a graphing and also capable of averageing , on the averaging readout, it shows 451 mv exactly.....So I punched that number into my haltech for closed loop target, and miracles of miracles, it shows up as 14.7:1 on the wideband, and while the autometer is flicking back and forth showing the cross over , the wideband readout is static...

Its only a matter of time, till we are all going to have Catalytic converters , vintage vehicles or not, people like the sierra club are suggesting that vehicles that don't have them be crushed , all it takes is them to be listened to by a politician with a granola complex and life can change for us pretty drastically, in Canada , it happened to us with the Kyoto accord, we still don't know what the goverment is going to push down our throats to comply with that ...Max

apreludem

hmm..i was just reading this and you guys mentioned "visual" portion of the smog test.....what do you mean by that exactly....the car will blow a lot of smoke or something?

HAILERS

The visual is........will the **** see the original airpump, acv, cat etc as they came from the factory. A Cadillac electric airpump going to the cat won't cut the mustard.

A Ford with OBDII has the two o2 sensors for each bank. One prior to each cat....one after each cat. With something like a Actron CP9145 (semi cheap/practical), you will see the o2 sensors prior to the cat jumping on either side of stoic. If you look at the o2 sensors after the cat...you will (should) see a static display. If those 02 sensors after the cat are jumping around..then the cat is not doing it's job and should be replaced (more true than not, exceptions are out there).

RETed

This thread creates a lot of confusion...

Closed-loop O2 is not a necessary feature. My tuning run all open-loop, and we run the maps lean enough under ligh-load cruising that they will rival (if not beat) stock mileage numbers. 15mpg mix driving is easy to attain; best highway mileage was 25mpg. This is all without O2 closed-loop enabled - the Haltech gives you the option to use this feature or not. I don't relying on O2 closed loop, because you're relying on the condition of the O2 sensor itself. When the O2 sensor degrades, it's reaction time slows down. Once it's reaction time slows down, performance is degrade and, thus, mileage starts to go down. In open-loop mode, dependency on the O2 sensor is negated, so there is no chance the mileage will suffer due to a fialing O2 sensor.

I recommend buying the product that you can get the best support for (locally). There is nothing better than running into a problem and obtaining a satisfactory fix quickly.



-Ted

apreludem

very good point.