1fastWS6

iTrader: (3)

At WOT on the dyno and on the street I'm getting 27.5* timing max. My HO and LO timing tables are both set to 28* timing in the .56-.80 g/s rows from 2500-7000 rpm. I've zero'd out the timing retard vs IAT. I was not getting any KR while logging.

Where else in the PCM (I have LS1 EDIT) should I look to see why it's still pulling timing? Before my last cam install I got 28* as expected.

jimmyblue

iTrader: (11)

What is your Dynamic Cylinder Air PID reading at WOT? I see 0.80s
and I don't even have a (non-stock) cam. The timing I believe will
interpolate between rows and if you are seeing (say) 0.82 for CylAir
you will be somewhere between your 28 degrees and {whatever is in
the 0.84 row}.

Also, check that the values in your timing table are not just being
rounded up, and really 27.5 degrees to begin with - I know in my
HPTuners I can up the decimal resolution and see that (after many
sessions of fiddle-and-smooth) I have a lot of non-integer values,
but if I display with zero decimal places they -look- like integers.

wait4me

iTrader: (10)

look at your mean best timing table for your year, it is set for a max of 27.5 at 80 gs/s
id up those values and then it should change your timing max values.

1fastWS6

iTrader: (3)

Thanks for the ideas guys. The MAF is seeing less than .80g/s at WOT in 4th gear. I'll check the decimal resolution, but I didn't change anything in the table from when I dyno'd it last with the smaller cam and it was getting a full 28* then. Oh, and this is a modified '98 timing table that I'm running. Anything else I can look for?

John_D.

iTrader: (2)

There is an ECT table that will reduce timing, but the coolant temps have to be fairly high. Also an IAT table that starts taking it out earlier. And of course there's knock retard... There's an AFR table too (although mine was all zeros). These are all in the timing tab in hptuners.

SmokingWS6

iTrader: (1)

Have you changed maf's to a non stock larger one? If so you'll need to scale maf table accordingly so you'll read the correct g/cly table.

Slowhawk

iTrader: (12)

My scanner sometime's will read .5 lower on max timing for the hell of it.I don't worry about it.

1fastWS6

iTrader: (3)

Hmmm, maybe that's it. AutoTap can be kinda glitchy like that sometimes.

I'm still running a bone stock MAF so that shouldn't be a factor.

Bink

There is an "EQ Ratio Spark" PID in the New EFILive Tune 7.1 software -
you can download a trial version (Beta). I suspect the new spark PIDS will be a BIG help in identifying the source of our final spark values.

-joel

jimmyblue

iTrader: (11)

Is this the same as the "Knock Learn Factor" I use,
or something else?

Knock Learn Factor being what steers the interpolation
beterrn High Octane and Low Octane tables, based on
knock history. If you see it less than 1.00 there is
some history of knock and you are being pushed toward
the low octane table spark value.

Bink

It's a different PID Jimmy - looks like there are several PIDS for Spark/Timing that are new. GMPX said we'd be able to definitively determine our spark origin with with EFILive V7 - with FlashScan we'll be able to adjust .

-joel