Thanks very much for the reply Ken, I hadn't read that no but had read
this which seems to cover most of it. The main thing I was struggling to get my head around was how it worked out the TPS change once you reached your Switchpoint, but I read the link you posted a few times last night and I finally got it I think.
So if I'm understanding this right, the ITB Load TPS Switchpoint should be the TPS% where you reach 90kpa. So this is saying, ok when I get to say 10% TPS I should also be at 90kpa, so I'm then switching to the Alpha-N area of the table.
Then the ITB Load at TPS Switchpoint is the partitioned VE table, so you're just saying I want this section for MAP based VE and this section for Alpha-N based VE. To get to each of these switchpoints it uses the previous table for when you hit the desired TPS%.
Now I kinda got that bit already, but what I was then struggling with was once it got the the Alpha-N area, how did it work out the difference. Which if I'm right, it's basically just a percent of the remaining VE area. So if at say 2109RPM my TPS% is 10.4 and the VE load area is 79.1. This means that if my TPS% was at say 50% at this point, it would be 50% of the difference in the remaining VE cells, which would put me at roughly 90 ITB Load. So basically it just divides the VE table above the switchpoint and the TPS% is the division of that area of the table.
Does that make sense?! lol I think I've got it anyway. I was previously thinking that say 50% at that same switchpoint would move you to a different switchpoint, but if the RPM was the same it wouldn't, it would just move you higher up the ITB Load table based on the TPS% which is worked out as a percent of the ITB Load after that switchpoint.
lol I know I've probably repeated myself like 10 times there, but hopefully I've got it right and maybe if I say/type it enough I'll get it right!!
Please don't tell me that's wrong now or my head might implode!! lol
Ok so the next question, not sure if you looked at my logs in that link I posted? But is there a best way to check your switchpoints? Like should I go through say 1st and 2nd gear from idle to redline but slowly increasing the throttle change, or can you just literally go WOT through a full rev range and you'd still get the same results to see where your kpa hits 90 at those RPM's to then set your switchpoints?
Also could incorrect switchpoints cause an issue where if say at 2900rpm with 13% TPS and at 75-80 ITB Load my AFR is at 14.9 which is correct, but then at the same RPM and Load my TPS% was 20 but my AFR's are then going into the high 15's and even high 16's?
Thanks very much.
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