Help Quick Fuel SL450SV & Y Block 292

[Eledu]

Dear .. I have a 1982 f100 (Argentina) with a Ford V8 292 Phase 2 engine (similar to the Y block, only the cylinder caps change) and I installed a quick fuel SL450SV carburetor with a single plane intake. The engine is stock .. electronic ignition and headers.
Originally the carburetor came with 56 primary jets and 60 secondary jets ... I put 55 primaries and improved a lot, the problem rises when regulating the secondary ones. When they open, bog is created instantaneously, the only configuration that works is opening the secondaries very little and almost at the end of the rpm (3500 of 4500). I don't know if the bog is caused by lean condition or rich. What do you suggest?
Attached images of the spark plug, the engine and the opening of the secondaries...

Greetings from Argentina!
PD: This website describes the differences between the American Y block and the Argentine phase 2
http://www.fordv8argentina.com.ar/di...sentref1f2.htm