Chris Conway

If you can do some basic electonics then it is possible to use an AD595 thermocouple chip with a voltage divider on the output. I am currently building an 8 channel system which works out at less than AUS$100 per cylinder (incl. sensors) for a range of 0 - 1000C with a 0 - 5V output.

Go to 'Fuel-Advanced' Select the 'Individual Cyl Fuel Correction' You can then decide if you want an individual table per cylinder. You can then set up the table with EGT as the 'Y' axis and RPM as the 'X' axis. The numbers you put in the table are a % of how much you want to adjust the main fuel table. ie. if the exhaust temp is too high then you may want to add some fuel in the approporate correction table, therefore put 10% (or some other +ve number) in the appropriate cell. The opposite is true if the fuel is too cold (subtract fuel). It is vitally important that the main fuel table is accurately tuned before you start with individual corrections. You should also ensure that all EGT probes measure the same temp. You can do this by moving the probes to different cylinders and checking that they measure the same for each cylinder. If the probes are not measuring the same then you could make the wrong adjustment and melt something.

See attached spreadsheet that may help.

I have been trying to find latency numbers for SARD 650cc side feed saturated injectors that are a direct replacement for Subaru injectors. Does anyone have some numbers?

Superb, I will give this a go. I assume that a water temp sensor would be suitable?

I have had similar problems which I believe are caused by 'heat soak' when the engine is turned off. What I have done is to add numbers into the 'IAT Fuel Trim'so that it will increase the fuel added. I add 1% @ 30C and up to 8% at 50C at a map of 30kPa. I then reduce the % trim to 0 by MAP=80kPa. The remainder of the IAT fuel trim numbers are what would be expected for changes in air temp. ie, take fuel out on hot days and add fuel in on cold days when the engine is on boost (> 140 kPa). I have also added considerably greater numbers in the fuel cell which is generally below the idle speed. ie,850 & 1000RPM = 70 at 30kPa, 700RPM = 78 @ 30kPa. This also seems to help maintain stable idle. I also used open loop idle speed control and fix the idle air valve position rather than using closed loop control.

I have used the 4D table for a very similar reason and have set it up as follows: Used Vitual AUX 1 as the activation by setting ECT>85C and MAP < 80kPa. The reason for this is that I did not want the 4D table to be active while the engine was warming up as this would cause the AFR to be too rich. Also did not want the 4D table to be modifying the main map when on boost. The table was then set up using the Gear number as the Y-AXIS and RPM as the X-AXIS. For gears 0,4,5,6 I set all the cells to '0' so as to have no influence. I then set gears 1, 2 ,3 with various % increases to get the AFR I wanted (around 14.2). The whole reason I set this up was to be able to run lean (16.2 AFR)at cruise loads (< 100kPa)for gears 4,5,6. When I used lower gears then the car would be a bit rough so I need to run at richer AFR (14.2) to get stability. I works fine and I get great fuel economy (around 8 L/100km).