NICK C
10-18-2013, 05:04 PM
I have FFR7622 with a 429 BB. I am installing Mass Flo EFI and am instructed to place the O2 sensor bungs 9 to 18 inches from heads. That would put me on a primary tube which I would think would be a limited sample. I have the Factory Five supplied headers for 429/460. Wouldn't the narrow part of the side pipes just adjacent to the collector provide a good sample. Thanks for your help. Nick C
Jason Lavigne
10-21-2013, 07:45 AM
Hi Nick,
My understanding is that it's more important to have the O2 sensor in the proper temperature zone than to have it in a collected stream. If you're only in 1 primary tube, but you're at the proper distance, then you've got a good reading on that one cylinder. The hope is that the engine is running well enough that it's representative of how the others are doing.
If you're too far away (in the collector), then you're likely to have a poor reading because it's too cold, so it won't have done you any good to move the sensor out that far.
Definitely run that by Mass Flow, too, because they may be able to get you a better idea of how much that temperature change matters or not.
Jason @ FFR