Running a VLT Tune on an NA computer

[Moss]

Hi guys quick question,

I have a VL which has been converted to turbo, running a lowmount T04E at 10psi and a front mount, with Turbo injectors and an NA ECU. It runs well but the bigger injectors tend to run the motor really rich, and it wastes alot of fuel.

Ive installed a Nistune, and for now, I just want to run the car on a standard VLT tune. I have a few things to install in the future (FF plenum, fuel pump, GTR injectors, etc) but for now I just want to retain a nice economy so I can cruise.

I was just going to run the NA tune but resize the tune to work with the turbo injectors, using the conversion. Obviously this would be just like having the NA injectors again, so I'd lean out on boost. Ive been told by a good friend with a bit of experience that I can just load a VLT stock tune, but it wont run properly due to the lack of a knock sensor (due to being an Na motor / ECU). I've found out that the knock sensor pin is #21, an this needs to be earthed, with a resistance (can't find the correct resistance, but it has been indicated around the 470-550 mark). I also have knock sensors and plugs on my spare RB20DET I could use, but would rather not bother.

So my question, which approach is better and will work?

- NA map with injector resize
- Turbo map, do nothing with any wiring (maybe delete the knock sensor part of the tune?)
- Turbo map, run a wire from pin 21 to earth @ 470-550 ohms (not sure what exactly obviously)
- Turbo map, run a wire from pin 21 to a knock sensor of my old motor, and hope that 3+ years out in the weather hasn't mucked it up.

Thanks for any help!

James

[bachig24u]

which nistune base image is on the Board?
Its either a CR31 or VLT that is hand written on the type 1 board.

Tell me what injectors you have installed (NA or VLT) and what the injector multiplier and latency values are in the tune file.

I make up hybrid tunes for these all the time with no running issues unless they aren't calibrated for the right combo.
We also used 1000cc's/90mm MAF pipes with no problem on an 3EA/3EM.3TA/3TMs.

[Matt]

See what part number Nistune reports. I usually load 23710-B49XX (VL RB30ET) into most Type 1 boards for RB30s

Lack of knock sensor on these earlier ECUs does not seem to matter like the later ones because it only is used to pull timing out where knock signal is encountered (in a particular area of code which I investigated). Where there is lack of sensor/knock board in the ECU only a fault code is reported.

Given the ECU is NA there will be no knock sensing board fitted anyway, so no point fitting the resistor (470K ohm) to the ECU knock line

Use the existing base turbo maps, ignore the knock sensor code (you can untick the 'knock sensor DTC' if you wish) and work from there

[Moss]

Sorry for the late reply, haven't been doing much with the VL lately as I've been flat out on my 180.

I haven't had a chance to plug the ECU into a computer yet, but as I am running Turbo injectors, I assume it is running the Turbo base file as it idles perfectly, much better than it did with the N/A ECU and Turbo injectors.

If all the knock sensor does is log a fault code as you say, then I'm happy to live with the error code, so long as it doesn't actually pull timing out of the engine.

Thanks guys

[Matt]

The code is simpler in the VL ECU and no timing is pulled with the fault code active

[Moss]

Awesomeness, thanks Matt, now to fix all the other issues with the bloody POS