cant go into boost please help

[jsbuickpower]

when i start to build boost at about 10 psi or so it miss or back fires my car was not running for a while be cause the maf was messed up i put a new maf i think from micro teck .last time i had this problem it was my fuel line going from the pump leaking do u think it could be the maf or my be the fp its a walbro 340 255 lph it has a racetronix hotwire kit

 

[ES1]

You need to put a fuel pressure gauge on it that you can see while under boost.
Needs to go up 1psi for every pound of boost.

It could also be a bad new MAF.