From what i have gathered the IAT vs Timing table appeared in obdii 96/97 lt1s and there after...

that must be hardcoded in the OS if it where a IAT thing...

But i feel there is such a table...

 

From what I've seen of timing vs. coolant temp tables, they don't start to "kick in" until the coolant temp gets rather high. So they probably aren't a factor.
Now timing vs. IAT would be a different story. If someone wanted to break down the code in the pcm they could find it. Maybe we should ask Tunercat if such a table exists? Heck, they found the forced tcc lock table that I was sure existed...maybe they'll find this too.
Only thing is this, whether it's july or december I still get the same amount of "mystery" timing at wot. So I'm doubting this would be the source as I'm sure the IAT temps are a little warmer in summer.

 

Tunercat assures me there is not such a table, which i know there has to be... i guess i'll run the disassembler to see what i can find...

Depending on how the table is setup you wont get any extra advance wether summer or winter... so that will depend.. but look at it this way... people use the IAT mod to get more power
timing and fuel

 

Ok , technically you won't.
But watch IAT's in warmer and cooler weather and tell me that there isn't a difference.

 

There is.. but what if that table is filled with +4 in the complete table?

 

If that were the case then why are we even having this discussion?
There would be 4 degrees of timing added in above what is shown in the 2 main tables.
I guess I understand what you're getting at, but odds are if there is a IAT vs timing table it isn't filled with the same value.

 

If you check uot the ls1s.. on the working range is more or less zeroed out..

 

Are we sure that the added timing reported in datamaster is real?? Anybody ever checked w a timing light. I believe some of the older TBI and TPI PCM's had a table for PE Timing Addr vs RPM. I'll have to look again to make sure. Maybe I've killed too many brain cells.

Steve

 

The pe timing could be... as there is one in the ls1s but im not really sure as this advance is seen all around.

 

I was thinking it can't be IAT timing table unless its based on RPM because its not just 4* everywhere, it adds 2* at 3000rpm, 3* at 4500rpm & 4* at 5500+ rpm or something rather.

 

Well... on ls1s is a vs g/cyl.. but.. hm...
it could be an adder for the PE vs RPM thing...

but i can see this advanced added regardless im WOT or not.

 

The timing you're seeing in Datamaster is real.

There is a universal spark adder at upper rpms that both LT1edit and tunercat refuse to admit, however I know of 2 guys that agreed on the section in the disassembly where it's at. Basically plan on 4 -5 degrees getting added in the upper rpm band.

Since it's also added to the factory spark values just move values relative to stock.
Doesn't matter what the number is, just how much you had to change it to make the engine perform better.

Oh, the IAT temp tables are only for extreme climate differences, nothing for normal climates.