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Hi,
Referring to a VX n/a V6 and TunerPro readings.

Is it normal for the Spark Advance to spike from 20Deg to around 40 Deg when coming off throttle to 0TPS% ?
The time to come back to 20 Deg can vary from 1 to 10 seconds on a log from TunerPro.

I can't see that it is meant to do this.

Yeah that is how they are tuned from the factory. Have a look at the spark map in the 100 grams/s column. That is basically then the throttle is closed and the engine is under high vacuum, it is possibly also engine braking.

All part of the emissions strategy the manual ones used to rev above 1000rpm if you clutched in was better for emissions to keep the revs up between shift. the later years there's no real decel when doing 50 due to high timing on closed throttle and targeted rolling idle speeds etc

Yeah it's quiet annoy when it stays above 1000rpm on decel, I've started pulling out a little timing and lowering the IAC settings.

Man I thought you guys were off the planet with those huge figures till I had a look. Holy shit was my exact words. All I can say is the fuel must burn real slow under those closed throttle conditions.

Yep it does. Even on the dyno I found MBT to be around 40-50º in the 30-40 kpa at high rpm on my VR. Iirc the early VN SV3800 ran almost 60º in those same areas.

Yeah at 50 g/s it goes to 47°.

Crazy why not just have a fuel cut to eliminate emissions. Maybe it's to do with the CAT.

I am glad that it isn't just my vehicle doing it. I guess at this point I wont play with those settings as It is there for a reason.
Though i would like to know if it is wasted fuel because of it?