What say you, Graham?

[XfireZ51]

Lance,

My point was that Graham did not experience significant divergence of BLMs bank to bank perhaps because the OEM injectors were better matched. Or since it was in the design phase, they may not have had the normal variance found on production pieces. More than 20 years later, various injectors are being used, w a difference in electrical and mechanical properties, and this could be aggravating the differential side to side. Throw mods into the mix and voila!
I'm no code writer, but it's my understanding that due to SPFI, it would not be hard to program individual L/R fuel trims to help even things out.
What's interesting is that it is almost always the left bank which runs leaner than the right. So it may not be injectors. This "split BLM" is not as pronounced in stock motors as it is in modded ones. And idle or low rpm operation has a greater degree of it than high speed cruising from my observation of it.