I'm doing my first tune on a friend's LS1 VT Commodore A4 using EfiLive and Flashscan.
The car has a set of Pacemaker tri-Y's and a Unifilter pod filter and inlet. It pulls about 165 rwkW on an old Vane dyno. The LTFT's are between 10 and 20% positive and the AFR's on my wideband show mostly 10.9 to 11.5 at WOT. The headers go from blue to red very nicely .
If this was an early SD Delco, I would adjust the VE's appropriately and it would be good. But I've read conflicting accounts of how the VE inputs are a low priority part of the fuelling filter on an LS1, which purportedly relies mostly on MAF inputs to set the injector pulse width. On this theory, altering the VE's is not the quick way to zero LTFT's, and may not even have much effect.
The EFILive note on the MAF table says something like "don't change this table unless the MAF is modified from stock"- and it's not. So if the VE's aren't worth changing, and you shouldn't modify the MAF table on a stock MAF, where to from here?
I'm planning to adjust the VE's to take account of the LTFT data, scan the PCM again, and then modify the MAF table until I had close to zero LTFT's. But a post from GMPX says + or - 5 is okay.
I'd appreciate some enlightenment please, Oracles
John