From a screenshot I saw posted here a over a year ago the ADAW bin in this ECM has a non-linear spark table with regards to the MAP. Has anyone verified if this is really so? I've not seen any other ECM's/Bins with anything but linear steps. Where in the bin are these steps defined, and would it be possible to alter them to ordinary linear steps?
Also, the rpm's only extend up to 2400. Would it be easy to change these steps too?
I did remap the L69 spark map to fit into the 8330 with good results, but some cold-start spark issues remains. I've located lots of tables but I just don't know which of them does what.
Any help with this would be greatly appreciated. I haven't found the time or energy to experiment or build a test bench to figure out all the tables by myself.
Why bother with the 8330 you might say.. I guess I could just as well get hold of the more documented 8079 and repin the connectors, but I'd really like to know all about the stuff I already have (plus it's cheaper too..).

 

What do you mean by non linear?

You'll need to learn to hac to do what you want.
The more you want, the more you'll need to learn.
It's almost no money, but it takes a whole lot of time.
See the source code for dummies sticky as a starting place.

Table steps are a result of the rpm calculation used.
Each calc stores the result to ram for use throughout the program.
Change the rpm calc or ram address used for the table l/u and you change the steps. You can also do some math to the value used prior to the l/u to change the step size.

8D has 3 rpm calcs, rpm/25, rpm/12.5, and what I call a scaled term for the third. I haven't studied the scaled term enough to explain it since it works fine as is when it is occasionally used in 8D.

You might also consider swapping to a newer dist and ecm and an older carb or tpi.

 

The MAP values were listed as: 55 51 47 42 37 33 28 24 20 10 8 6 4 2
I did find it strange, and for all I know it could be intentionally shown that way to throw off "leechers". My initial understanding was that these steps are usually part of a formula. So I'll "just" have to locate the calculations in the code then.

Yes I know, and if I had felt capable of disassembly I'd have done it and posted the results years ago. Maybe if I had come across this need something like 15 years ago I figure I'd have tackled it, but the later years have been a challenge just getting through each day on it's own.

I am able to read a hac and understand what some of the code does, but disassembling the full 16k of code is too much for me right now. The car will be scrap before i finish. I'm basically an electronics guy even though I have done some simple programming, so my way of dealing with this would have been to build a test bench and then just experiment with the code (like probing the brain of a rat). But that would also take time, more gear & money, and give limited results though.

Most car guys here told me to just swap the carb & dist to the old kind, but I don't like to remove stuff just because I don't understand how to deal with it.
The easy way out would be to just get the ECM usually used for my engine, it only needs a few pins swapped plus some way of dealing with the A/C.

Thanks for the explanations about the basic operation of the tables though, every bit is helpful.