first gear pulls good second pull very good and third it back fires and feels like boost cut but my data-logs don't show it. Boost cut is at 12.0 psi and datalog show 9.6psi

Fully built b16 60 trim 440cc injectors

hondata s300

 

Do you have a wideband oxygen sensor gauge installed on the vehicle?
If so, what are the air fuel ratios at during full throttle 3rd gear full boost?
If not, get one before proceeding.

 

See above and in addition, check your plug gap.

 

What's the duty cycle on the injectors?
What do your timing tables look like?
and as mentioned above: AFR's and plug gap...