Why are our kPa increments so odd?
#1
Boost Pope
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Why are our kPa increments so odd?
All this talk of maps and values got me to thinking...
We all seem to be using pretty much the same basic VE and Spark tables. I'm guessing that DIY was the originator. Does it bother anybody else that the steps between kPa values on the veritcal axis of all of our tables are really uneven?
Take the attached picture. The numbers in green are the actual kPa values that appear on the left side of my VE and spark tables, and the numbers between them in orange represent the difference in kPa between the two adjacent cells:
Up in the boosted area, there are 28kPa between each cell, apart from the top-most one (which is really just a pad, I don't plan on boosting to 230kPa.) Down in the atmospheric area, it gets weird.
I can understand why you'd want a little more resolution down at the very bottom, but what about the cells from 35kPa to 100kPa? 20 kPa each for the first two steps, then 9, then 16. Whiskey Tango Hotel? Is there some amazingly straightforward and logical explanation for this that I'm missing?
We all seem to be using pretty much the same basic VE and Spark tables. I'm guessing that DIY was the originator. Does it bother anybody else that the steps between kPa values on the veritcal axis of all of our tables are really uneven?
Take the attached picture. The numbers in green are the actual kPa values that appear on the left side of my VE and spark tables, and the numbers between them in orange represent the difference in kPa between the two adjacent cells:
Up in the boosted area, there are 28kPa between each cell, apart from the top-most one (which is really just a pad, I don't plan on boosting to 230kPa.) Down in the atmospheric area, it gets weird.
I can understand why you'd want a little more resolution down at the very bottom, but what about the cells from 35kPa to 100kPa? 20 kPa each for the first two steps, then 9, then 16. Whiskey Tango Hotel? Is there some amazingly straightforward and logical explanation for this that I'm missing?
#2
DEI liberal femininity
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Join Date: Jun 2005
Location: Fake Virginia
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haha I noticed that when I was porting my hydra map over too.
I think you'd want 3 cells for idle/fast idle, then maybe around cruise, moderate load, then right around 101kpa, then every couple PSI.
so like 10 kpa, 25 kpa, 40 kpa, 65 kpa, 83 kpa, 101 kpa, 120 kpa, 140 kpa, 160 kpa, etc.
I think you'd want 3 cells for idle/fast idle, then maybe around cruise, moderate load, then right around 101kpa, then every couple PSI.
so like 10 kpa, 25 kpa, 40 kpa, 65 kpa, 83 kpa, 101 kpa, 120 kpa, 140 kpa, 160 kpa, etc.
#4
Only reason I have kept it scaled like that is because I ran their timing map for the longest time and I didn't feel like making up a new one. You could easily rescale though and enter your own semi-conservative timing values in by looking at the DIY map.
I keep my fuel map scaled that way just so that they match. It's also nice to have everyone on the same scale when comparing things.
i set the second from the bottom cell to whatever KPA i idle at, the 2nd one to my fast idle, the one above that to whatever I cruise at. Atleast that's how I used to do it. Makes it easier to tune by hand when its not interpolating between two cells. Now that MLV works for me though screw hand tuning.
I keep my fuel map scaled that way just so that they match. It's also nice to have everyone on the same scale when comparing things.
i set the second from the bottom cell to whatever KPA i idle at, the 2nd one to my fast idle, the one above that to whatever I cruise at. Atleast that's how I used to do it. Makes it easier to tune by hand when its not interpolating between two cells. Now that MLV works for me though screw hand tuning.
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