Boosted_One Posted July 3, 2005 Report Share Posted July 3, 2005 Kev-What WBo2 are you running? I found out that the display for my Tech Edge unit is terribly inaccurate, I have to use the numbers from megatune and my datalogs. Is there any way you can check your meter against a known good one? When my display reads stoich, the actual is close to 17.5:1. My tech edge was right in the window as my dynos WB O2. I use the Tech Edge display and the Tech Edge ECU. Wonder why yours is so far off??? Some tolerance error. They have instructions on how to bias the units output to compensate for the display error, but then the MS logged readings would be off. I'm pretty disgruntled about the whole mess. Their new units use a digital connection to the display so there can't be an error there, but there's a long thread in their support forum about the problem. I need to find a calibrated unit and just verify the MS readings. SUPPOSEDLY the output of the unit is correct, but I'm still leary. And I was wondering why I had severe detonation at richer than 13:1. There's a program you use for the tech edge unit to calibrate it. I know on my tech edge I use a VW WB sensor and the actual WB ECU had to be calibrated (from Tech Edge) to that sensor as there is some variation between sensor types, even if they are LS1, HUEGO, etc. Link to comment Share on other sites More sharing options...
Vanishing Point Posted July 4, 2005 Report Share Posted July 4, 2005 I think fuel is a red herring. I've swapped injectors, injector bank wires (the megasquirt is BANK fired, 2 banks), eliminated the vacuum port on #4, checked the plug wires, done a compression and leak down test, checked the injector sound with a stethescope. I think the plug being black is caused by oil as it has definate oil residue after 5 minutes. Since compression and leakdown are excellent, guessing valve seal. This, however, does not explain why it won't run well at 14.7:1. Perhaps I'll double check my wideband with a narrow band. This is frustrating.Holy crap that would suck if you went through all that because your A/F meter was out of calibration. At least you may have found a future oil problem :? I have only used the narrow band and it does everything I have needed. I suppose if you wanted to dial a race engine in perfectly repeatedly you would care if you was running 12.5 to 1 or 12 to 1 A/FBetween the narrow band and the lean/rich knob on the SDS I think I have gotton dialed in pretty close. Now it would be nice to know what A/F ratio made the best power on my setup so if I built another I could tune for that.SDS says MOST engines will make MAX power at .76 volts narrow band. You may find to much pre ignition at that setting. I went rich to stop it then backed it back off and bought the race gas. I may try the water injection thing next year just to say IM running pump gas.Tony Link to comment Share on other sites More sharing options...
kev_rm Posted July 6, 2005 Author Report Share Posted July 6, 2005 My wideband may be suspect, but it's a fact 0.76V doesn't mean ANYTHING on a narrow band other than it's richer than 14.7:1. Narrow band only provides two data points - leaner or richer than 14.7:1. Every other data point is highly dependant on EGT. Link to comment Share on other sites More sharing options...
Vanishing Point Posted July 6, 2005 Report Share Posted July 6, 2005 My wideband may be suspect, but it's a fact 0.76V doesn't mean ANYTHING on a narrow band other than it's richer than 14.7:1. Narrow band only provides two data points - leaner or richer than 14.7:1. Every other data point is highly dependant on EGT. Wow Kev, I was just trying to help. I am very happy with how my car is tuned and running, but I tune loops for a living. Its a FACT you have been kicking a dead horse because your WB calibration is off.I would be pissed if my $300 wide band didnt work right also. .76v was picked by SDS as a starting point. They have done more of this stuff then I ever will.Good luck I do hope you get it calibrated and can just tune and drive for fun.... been there.Tony Link to comment Share on other sites More sharing options...
artinist Posted July 6, 2005 Report Share Posted July 6, 2005 under high boost mine likes to run around 11.5-12:1 Link to comment Share on other sites More sharing options...
Boosted_One Posted July 6, 2005 Report Share Posted July 6, 2005 under high boost mine likes to run around 11.5-12:1 exactly where you want it too... Link to comment Share on other sites More sharing options...
kev_rm Posted July 7, 2005 Author Report Share Posted July 7, 2005 tony, I appreciate your sympathy don't trust you're narrow band too much, that's my point, however badly that came across (and misguided since my wideband is suspect) Link to comment Share on other sites More sharing options...
heefner Posted July 7, 2005 Report Share Posted July 7, 2005 exactly where you want it too... 11.5 is a little too rich for me. Check out this article on tunninghttp://www.innovatemotorsports.com/resources/rich.php Link to comment Share on other sites More sharing options...
Vanishing Point Posted July 7, 2005 Report Share Posted July 7, 2005 tony, I appreciate your sympathy don't trust you're narrow band too much, that's my point, however badly that came across (and misguided since my wideband is suspect) Thanks, I know anything above 13.5:1 could be off on the narrow band. Thats where the mixture knob came in handy.I should really put my car on a dyno, but its running so good now I would hate to change it.I dont know what your manual says for checking calibration on your WB, but industrial gas places sell all kinds of nitrogen mixtures. You maybe able to find a lab that can rig something up for you.Tony Link to comment Share on other sites More sharing options...
Recommended Posts