I just finished replacing a bad AFPR, and also dropped in some new SVO 30# injectors (set my injector constant to 33#).

After the upgrades, I took the car out for some 900-1600rpm cruising in order to gather data for my lower VE tables.

I was able to gather about twenty-five different points (some duplicates) worth of rpm/Kpa ranges, but now I've come to a point where things aren't as "accurate" as I would like when I started plugging numbers.

Take for example these numbers:
1400rpm 48Kpa 108blm
1400rpm 51Kpa 110blm

Looking at the Lower VE Table, I notice that the Kpa numbers are in 5 Kpa incriments. How does the computer differentiate between these "floating" Kpa figures? By floating, I mean my actual Kpa figures as opposed to the table's 5Kpa incriments (ie: 48Kpa and 51Kpa as opposed to say 45, 50, 55Kpa etc. on the table). I'm thinking the non-programmable logic operates in one of three ways.

1) Bases the actual Kpa to a "rounded" number. Rounding to the nearest number on the table. Example: 48 would be used as 50. And 51 would be used as 50.

2) Rounds up to the next Kpa once the Kpa on the table has been passed up. Example: 48 is used as 50 on the table, and 51 is used as 55 on the table.

3) Stays at the table Kpa until the next table Kpa has been reached. Example: 48 stays at the 45 table area, and 51 stays at the 50 table area.

So my main question is, do I simply round to the nearest Kpa figure, and plug the numbers for that block or what? I know I'm probably reading into this too deep. As far as my first few burns are concerned, I know it's not important how the computer rounds the Kpa figures. But I'm a perfectionist, and in the future I'll definately be diving deep into a perfect VE table. A perfect VE table meaning a few different chips for different seasons since ambient temperature changes things alot (my IAT is relocated), and for different driving styles. I'm obviously new at this and still have A LOT to learn.

Any and all comments are welcome, even if you say I've no clue what I'm talking about...Which is quite possible.



------------------
86 Trans Am WS6 Black with tinted windows, ZZ4, Mini-ram, true duals, LT4 HotCam, AFR 195 heads.
***Too many other mods to mention***

"In the future, cities will become deserts,
roads will become battlefields, and the hope of mankind
will appear as a stranger" The Road Warrior

 

Good question Steve, I would like to know/understand the same thing, it would be very helpful. I know they slide in and out from cell to cell so its really hard to decide on which ones to alter. I just change them a little at a time where the data tells you to change them. By a little i mean. .4 or .8, then run it again to see what you can come up with.

Brendan

 

Thanks Brendan, I guess I'm not the only CrAzY one here then.

Now I AM going nutty!!!...I was just thinking about the Upper VE Table just now. Instead of us simply worrying about a 5 Kpa span on the lower, the Upper Table representing the 1600-5600rpm range has a whopping 400rpm span along with a 10 Kpa span! I know that the air flow variances become more linear at the upper rpm and less vacuum ranges (kinda like head flow bench numbers), and I wonder if this is the reason for such a great span on the upper tables???

It'd be nice to learn why these tables are set up like they are.

 

Start again, use the 33 injector size, and relocate the IAT to where it was originally.

Then drive around some an see where your BL numbers are. The move the injector size around some and see if that doesn't take care of you BL numbers or at least get you close.
Then fine tune your VE entries, and work back and forth with timing since it will have an effect on what the VE entries need to be. And VE entries will have an effect on detonation, and also timing.

One change at a time, and just do what makes the egnine happy, not what you THINK it needs