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Most of the problem with hot soak is when the vehicle is idling and not moving such as at traffic lights.
Once up and moving is normally less of an issue.
Unfortunately means that at the traffic light drag can be sluggish to get going, on a track day is less of an issue.

Most of that is in the tune, there are setting for lower timing as safe guards when temps are high against knock. If you run 95 or 98 it becomes a non issue so you can 0 out those tables and settings. Which is what I do on all my cars so heat or not the performance is not affected and performance is consistent.

Did a cold start log. I see that as it's cold the WB is a fair bit leaner than the target and at certain temps very lean and is probably what causes it to randomly stall during idle warm up, some points I saw 16 afr on idle. However once it gets to about 60c it stabilizes and the target/WB converge. At full operating temp it's all fine.


So not having done much on cold engine warm up tuning as most engine I worked on were fine with stock settings, what is the best parameter to adjust to bring inline without throwing off the main tables like VE etc ?

is it the inverse temp table vs charge temp? or should I fudge it via the initial run AFR offset table? I know the latter will not affect the other tables, not sure about the prior.

Anyway the BIN and log attached, just the standard 12P v112 xdf and adx was used.




Just a thought, I got 6 hole ford injectors. I seem to think they had a wider spray cone and finer mist. The stock injectors have narrow cone that hits the back of the valve. I wonder if the fuel with these newer injectors are sticking to the walls? only vaporizing once warm enough. It would explain the unstable and leaner cold conditions as well as poorer cold AE behavior.

I use the inverse temp table mostly.

So make say 50c and bellow more negative on the right column?

Yep, make a fairly drastic negative change and blend it from say 50-60 downwards. Get the line graph up and make a nice shape out if it.

Now many deg should I change it by? will 5c be enough as a starting point?

Maybe knock it back 5 at 60 and taper back to -20 at the coldest set point.

Why is it with that table no matter what values I have it's a straight line graph. Am I reading it wrong?

Works fine here, I started with -5 offset at 44 to -10 offset at -40 and made the line straight from those 2 points.

Will try it in the morning when everything is nice and cold.