I am looking at the Ignition Map Load Calc sub on the H8s.

I know MrFred has posted the the Load Decision before, LoadIATBaro if Air Temp > 77*F, else LoadBaro.


But there seems to be two Compensation tables that are added to the above Load.

I was wondering if the Evos also have this Compensation?

And what the Compensation tables axis are? (Axis lookup is hidden in H8s)


The math is a little funky, but it looks like these Compensations could have a significant effect on final Ignition Map Load.


Thanks much for any info.


Edit:
The first Comp table is used when MAF is unplugged or the car isn't running, I think.

But, the second table is for normal use and has high compensation at is top end.

 

Can you specify locations in H8?

 

20550011

IgnMapLookUp
calls->LoadCompAdder
--------calls->LoadDecision

IgnMapLoad = LoadDecision + LoadCompAdder

IgnMapLookUp = 26086
LoadCompAdder = 261B3
LoadDecision = 26208

CompTable_Limp/NotStarted? = 2EC90 Points to 12628

CompTable_Normal = 1261A



Do the SH ecus have something similar?

 

Yes, but only in Evo9
The map does IAT LOAD compensation.

Load is either Baro compensated or Baro and IAT compensated (10E58 limit in your case)

Evo 9 uses RPM based compensation.

 

So that map is a IAT compensation?

So basically at high temps the Load is compensated twice for IAT?
(Once from the table and once because its LoadIATBaro)

[And the Lookup is thirdly compensated by "Ignition Trim vs Air Temp"]



I ask because I'm changing things for my new version of "BigMaps".
Making Fuel and Ignition maps same size and use the same Load, for easier, more consistent tuning and logging.

I think if I use LoadIATBaro all the time for both maps it will be ok, but want to make sure the Comp table isn't necessary for safety or something.

 

I do not see your point

In 26208 depending on 10E38 either Baro compensated or baro and IAT compensated load is taken.

 

I thought you meant 1261A was a IAT Comp.

Its not WarmUp, that has its own 3D map.
And it modifys the axis Load, not like a normal ignition trim.


In 26208 Load decision is based on:
mov:g.w @AirTmp$_F22A:16, r0
cmp:g.w @word_E58:16, r0
(E58=0x41=77*F)


Maybe we're looking at different things.

 

Yes, probably I have misunderstood it Or I have had insufficient coffee level

It is similar to IX.

Just the value in IX (88590015@134A = 0 in IX) makes this adder as not used, 20550011@A24 = 7 in your case is different thou.

So for 88590015 LoadCompAdder @ 1BC6C
RPM Axis
@6B70
Tables
@3C6A,@3C5A

 

In the H8s this appears to be a Tip-In Compensation.

A24 = 7 is multiplied by a TPS_Delta, then that is multiplied by the 1261A table.
Only the high word is kept and is added to the Load used for Ignition map lookup.

So if there is a large TPS change, Load is increased, and as a result Timing is decreased because you are higher up in the map.


Kind of a round about way of doing it, but it probably produces a better Timing Compensation.


Thanks for the Evo9 addresses. I was trying to find it in the Evo roms with no luck.