Timing tuning..

[fasttrackperformace]

I am messing with a 347 forged ls1 with lower compression. The engine has a truck computer, harness, and tune on it. The high and low octane tables are copied, the ect and iat spark tables are zeros in the area of operation, the knock retard tables are zero'ed (trying to find the issue), and the burst knock tables are zero'ed(trying to figure the issue).

I have always looked over the historgram at the g/cly that the engine was operating under boost to alter my timing numbers for them drop under boost. The timing number that the scanner shows for the certain cell vs the g/cly during the pull is much lower then the numbers in the tune.

Attached is a log from a dyno pull and a tune. Say your looking at 4724 rpm, the g/cly in the historgram shows .80 g/cly and 4.8 rpms and 17 degress of timing. The tune in that same cell reads 19 degrees. TIA.

[WS6FirebirdTA00]

Delete the MAF PID, you are halving your g/cyl because of it. When you are in SD, there is no need to log that stuff anyway really. Try that first, that may be what is giving you oddball data.

[fasttrackperformace]

I think that was a problem before and I forgot . Thanks

[fasttrackperformace]

Here is the next pull with the same tune, just the deleated MAF pid, it follows the 1.20 g/cyl row but the timing is different in the logs then in the tune.

[WS6Fury]

Don't zero out your knock tables, that's asking for trouble if something goes wrong. Just log the knock tables in the scanner and it will tell you if its compensating for knock.

Seeming like you took everything else out, torque mgt sometimes will play a roll in cutting timing down. Look at your other spark tables too just to make sure your not operating in a cell that may be cutting spark (ie IAT Spark - too hot, too cold outside, etc).

[fasttrackperformace]

This car has alot of false knock for whatever reason....and at this point we have plenty of octane just as long as the boost does not go out of control.

The problem is the timing is higher then the actual numbers. Almost all of the tables take timing away, that I am aware of anyways.

[tahoe]

This was easy, you add the same timing in "afr spark correction add" as stock,
i.e at 4400 rpm and 11.77 fuel/air ratio you add 4 degres.

At 4400 rpm and max cyl air mass, you comand 14 degrees, add to that the "AFR correction add" of 4 degrees, and you have the explanation for the scanned 17,5 degrees.

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[fasttrackperformace]

I zeroed that table out late last night but did not get to make a pull with it like that. Thanks for the help.