individual cylinder trim, need help to figure out why they are so different

bank 1 was always trimming more fuel then bank 2 from initial setup,but after doing a individual cylinder check i had some very weird results, cyl#1 -20%, cyl#2 -21%, cyl#3 0%, cyl#4 +14%,cyl#5 +4%, cyl#6 -1%, cyl#7 -34%, cyl#8 -31%. i just can not explain these reading

Hi Ben,

Can you please post up some more details of your setup? Car, engine, ECU type etc. Also can you describe how you're measuring your lambda? Do you have one wideband lambda sensor at the collector? One per bank? One per cylinder? The amount of variation you're seeing there is quite significant and doesn't look normal (unless you have blocked injectors or something like that)

Cheers

car is a 1996 holden commodore ute, engine is a N/A holden 355 running a haltech elite2500 ecu, it is running a camtech 290/290 hydraulic roller cam, edlebrock 1000cfm throttle body 42lb bosch injectors, full sequential injection and direct fire ignitionalong with banked o2 control in the collector.

these cylinder trim reading were were taken in extractor approx 75mm from the exhaust port, and all injectors have been serviced to rule them out of being the issue, also the issue does not follow the injectors if swapped to different cylinders.

Here are plugs before the changes were made to the cylinders

Does the engine idle nice n clean? Possible air leaks?

Idles good. No leaks