By 15%/20% do you mean a value of 15/20 or 15/20% of the value that was originally there?


Edit: sorry, I see now that on the IX 15 rom these values are percent, but they are volts in some earlier roms.

 

Hey guys,

I have a long drive coming up and wanted to get this done!

One question:

Is it still worthwhile running a 15.8 AFR in the cruise part of the map (30-80load, 2000-3500rpm) WITH EGR?

Or did we decide that if you have EGR then don't bother?

Also:
If I do this mod do I need to worry about my CAT?

Cheers
D.

 

Even with EGR, this is a benefit. Most people think that the higher EGT's being recirc'd will hurt the gains from the leaner mix but no matter how you toss the dice...you're using less gas on your trip. Aslong as EGT's stay below 1500*F for long periods of time, you should be ok. If you start to hear some misfiring along the trip, its probably from prolonged EGT's. I know long distance drivers that run in the 1500* range for over 16 hours without fail, granted the car is tuned quite well for this stuff.

I'd set it for around 15.5:1 and be done with it, thats where I set my zeitronix NB simulator and it seems to be a good, well rounded setting for EGT's and fuel economy.

 

Would you really see elevated EGT's at cruise?

I mean maybe up 10% or so, but surely nothing dangerous???

 

I shouldn't try any of this without a WB huh? The LC-1 is cost effective, but I really would like to know if it can do the narrowband switching point. ECU+ has the variable front O2 switching point, anyway we can work this into EcuFlash?

 

I wouldn't suggest messing with the open loop alterations without a WB personally. Zeitronix can do the NB switching point very well and very easily and I consider it to be superior product for the $$$. All depends if you ever want to use the WB for anything more than JUST a WB reading though.

 

You can get over 1500*F just during cruise. Start leaning it out too much and you're approaching 1550*F which too close to the 1600-1650* cut off point even at a WOT run for short periods of time.

 

i know a guy running in open loop (not stock ecu though) cruising at 17 afr, egt at 750-800 deg C, with no prob.

i guess you could even go up to 16 afr with egr... but to be on the safe side, if you don't have egt reading, 15.5 is the best

 

OK I got done setting it up the way you said on my Evo Ix. And set it to switch at 15.5 afr, but the real time data on my gauge keep on going from 15.9 to 13.7 at study cruise not like when the stock sensor was connected your gauge will read 14.7 at cruise. Now for the last 3 day I am getting error code # P0134 ( Oxygen sensor circuit no activity detected bank 1) I thought the zt2 will send a default 14.7 afr to the ecu! how can I get around this. #2 does the narrowband output pin should be set to 0V-1V as it is now or going for 0V-5V will help. Thank you for taking the time to help me out guys.

 

been pointed out to me that the innovate software does allow you to alter the switch point of the NB simulator.

Has anyone tried changing these settings?

http://i64.photobucket.com/albums/h2...yfox21/lc1.jpg

 

hmmm, ooooh that's how you do it w/ the programmer. Yes, I've used that screen a long time ago when I hooked my LC1 up to the OE NB input on the ECU. I just used it to emulate the NB and take the whole NB sensor out of the loop. It worked great. I didn't think about the fact that you could use it to change the switch point.

 

Does the switching point apply to any closed loop operation? Meaning if you set it at 15.5, does that mean that your idle will be 15.5 as well as low load cruise?
I don't think i connected the NB wire on my ZT-2 when i installed it, but i may do it if it's a better option than adjusting fuel/tps maps. I'm just not sure about lean idle with 280 cams.

 

It changes the NB switching point for ALL closed loop operation. Idle and cruising. With cams you probably wanna stay in the 15.5 area, stock cammed people have a better chance of pushing it to the 16.2 range without affecting their idle too much.

 

You'll always see you're closed loop AFR fluctuate during cruising. The idea to to TRY and achieve the traget AFR but it will fluctuate higher and lower usually.

The ZT2 doesn't send a default 14.7 to the ECU, it sends a simulated NB signal which you are changing the target AFR with (you said you changed yours for a target AFR of 15.5 so thats the simulated target you are sending tot he ECU). A P0134 code means the ECU isn't seeing ANY signal at all from the stock O2 sensor or the ZT2. How exactly do you have the ZT2's narrowband output hooked up to the ECU?

DO NOT use the 0-5v output!!!!! Unless you want to fry your ECU! The 0-5v output has NOTHING to do with the narrowband simulation. That is for a WB "analog output" for a stand-alone ECU. Its a multi-use output which you set to do one or the other.

 

Make sure you hooked it up like this: