Quote Originally Posted by EyesofThunder View Post
Was experimenting with the Dual Bank/Single Bank on my L29 454 today, no worky (I know, I have a dead right bank O2). But looking at the L30 (the 305), it is factory single bank and works (obviously or GM wouldn't have shipped it), but it also has 3rd O2 sensor checked too. I will experiment more tomorrow on it.

The other question is did GM do something like ground out the Bank 2 sensor input?
Yes the Vortec 305 has that 3rd precat O2 sensor and the single aftercat O2 sensor.
The L31 350 and L29/21 454 uses the dual precat and dual aftercat sensors.

peace
Hog