TunerStudio and Microsquirt

Fair answer thanks. I was overthinking it again.

It's going on a Ford 2.0 dohc out of a Granada. It's in wifeys Ford Pop project.
It's all wired, sensors are working, most parameters entered as much as I can.
It's the afr table that's causing angst, I'm really struggling with it as in I have no idea how to build the table. I know how it works but relating that to a figure that needs to go in the box(s) is not computing.

It's not a paid version at the moment. I probably will pay at some point.
It has a wideband lambda sensor.

I still have to synchronise the ignition but I'm fairly confident that 80deg is correct as it's using the standard 36-1 internal toothed wheel and standard sensor position.

The AFR table is a target table, to help guide the ECU as to what air fuel ratio it’s aiming for when it’s running in closed loop (constantly referencing the lambda reading and adjusting trims to try and get you on target) or when you are using the ‘auto tune’ feature to find tune your VE table.

The AFR table doesn’t need to be especially complicated, many of the cells will be the same as each other. Theres plenty of discussion online about what AFRs give the best performance and economy, but below is my rough understanding.

14.7 AFR is the mathematical ‘perfect burn’, and you could do worse than setting the whole table to this value, it would be like you were tuning with a narrow band lambda sensor.

Best full throttle power, for NA applications, is found at 12.7-13.5 AFR, depending on your specific engines needs. So set your top couple of N/A rows, say 80-100kpa (presuming you’re tuning using speed-density) to this.

On older engines you may find the engine will struggle to idle smoothly at 14.7, it might be happier at high 13s, low 14s, you can experiment with different values in the idle area. Just remember you’ll need to put it back to 14.7 to give you best chance of passing an MOT emissions test.

You may find that you can eke out a few more MPG by cruising leaner than 14.7, somewhere in the 15s, maybe even as lean as mid 16s depending on the engine. Once you’re up and running you can find out where the engine is on your table when sat doing 40-60mph on a flat road and populate this part of the table with leaner values. You may need to alter the ignition timing to maximise the gains here and keep an eye on temps and an ear out for knock. It might be easier to just leave it at 14.7 for cruise and save all the hassle for a few percentage if mpg… haha.

Finally if you are boosted then your low boost values will want to be 12.5ish, as the boost builds (say past 1 bar) you may find it better to be running as rich as mid 11s. Or you engine might not need it, depending on the fuel you’re using, the efficiency of your intercooler etc. boost is a whole other can of worms. Main thing, it’ll be richer than the n/a part of the table!

As I said before don't worry too much about the AFR table, as long as its ball park, it will be fine, especially with an N/A build.

For reference, here is a quick table I put together for a friends Mr2 turbo build. Note that it's a turbo car, so the KPA values on the vertical axis go up to 1 bar of boost.



You will still want it idling pretty close to 14.7 in order ot pass a basic emissions test

Thanks Goldnrust and Kevins.
Some of the issue has been that despite being a new project the tables that came up were clearly for a turbo motor. I changed the scales to suit straight away and then started to ponder on what to put in the cells.

Kevins, thanks for that nugget of information, just the sort of thing that helps. I have put together afr and ignition tables that should get me in the ballpark initially. I'm reasonably confident of the rest but proof of the pudding and all that.

I set to yesterday and made a timing indicator tag. There's no timing marks on these engines but I did notice a small notch on the crank pulley. I also had a hunch that I had left the engine at tdc on number one bore. Plug out and quick check; yup, good to go.
I made a tag wit 0 degrees and 5, 10 and 15 btdc on it. All ready to check the timing in the ECU.
I'll detail that in my build thread.

I appear to have a problem with the crank sensor. Tuner studio sort of sees it initially (rpm) but then its gone. The synchronisation error light is on as well. I have done a tooth log and it doesn't look at all right. Oh, also the pulse width is off the dial!!
Any thoughts/ideas?

the way its going up and down in waves isnt right its getting confused.


" try a 10K resistor in parallel with the crank sensor"

click here

on my bmw with the cossie crank sensor i have to use the resistor.