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nathans1987
March 11th, 2009, 03:34 PM
What is the best way to tune the VE table without a WB oxy sensor? i'm guessing it can be odne because of the amount of mailorder tunes around but there isnt a tutorial on it. i tryed to use the same conncept as using the WB one but the map chart dosent work only 2 spots had a number in.

WeathermanShawn
March 12th, 2009, 03:37 AM
Theoretically you could use the feedback from the narrowband O2 sensors. They are designed to switch rich-lean, etc,, at ~14.63 AFR. If you disabled LTRIMS, and followed the tutorials to force the car into open-loop (just like AutoVE), the STFT's variation (positive or negative) would tell you the variance from 14.63 AFR.

You might have difficulties as engine load increased, and in those areas where you need additional fuel. You have no way of knowing whether you were getting the correct AFR ( the narrowband accuracy is designed to operate only at ~14.63 AFR). You would risk either too much fuel, or worse not enough. Detonation could cause significant engine damage.

I would simply advise to get a wideband.

joecar
March 12th, 2009, 07:34 AM
Nathans1987,

Welcome to the forum...:cheers:

+1 on what WeathermanShawn said.

LC-1 = $200

Replacement motor = $4000+

FlashScan V2 has a serial AFR intereface that recognizes the serial AFR output from the popular widebands (i.e. install the wideband sensor into exhaust header (in place of the NBO2), plug the sensor into its controller, connect the controller to FlashScan V2's serial input using a serial cable).

Also note that withe a wideband you can get your tune dialed in very quickly (some people can do it in one or two 20-30 minute drives, plus a maybe upto an hour for idle tuning) and very precisely.

nathans1987
March 13th, 2009, 03:40 PM
does a LC-1 for $200 come with a controller and where in perth would i get one.

mr.prick
March 13th, 2009, 04:28 PM
does a LC-1 for $200 come with a controller and where in perth would i get one.

The LC-1 is the controller, and you will have to wait until one of our friends from OZ sees this thread to find a place in Perth that stocks them or buy one online.

nathans1987
March 13th, 2009, 06:16 PM
so i can use my curren o2 sensor?

joecar
March 14th, 2009, 05:34 AM
The LC-1 controller uses the Bosch LSU4.2 wideband lambda sensor.

Your current narrowband O2 sensor will not work.

WeathermanShawn
March 14th, 2009, 05:39 AM
Nathan, when are you asking "Can I use my current O2 sensor", do you mean your factory O2 sensor (narrow-band), or do you have a wideband O2 sensor?

I would only advise utilizing the narrowband O2's for light or part-throttle areas of your VE Table below 2000 rpms. There are many write-ups on this tuning method using LTFT's and STFT's via Google or other tuning boards. However most were written before the days of EFILive or other advanced tuning software.

EFILive supports the use of many differing types of widebands for logging. You can hook up supported widebands via a serial cable when logging. You get instantaneous and highly accurate AFR readings.

You need a wideband to safely tune your car. Then you can use feedback via the factory narrowbands to fine-tune your VE Table.