bogs under throttle

So I did the fuel pump relay mod and now my car bogs under any throttle but eventually evens out, like after 3-5 seconds. My mechanical timing is off a little according to the timing light, it read 6 degrees btdc and when it flash, the pulley timing mark was straight on 10. Could the relay mod have caused my problem?

Also, it feels like it pulls timing under boost quite a bit, mostly under 3000rpm. After that it might misfire under full boost (4 psi) which I feel is unacceptable given the low amount of boost and good condition of the electronics and wiring. The corner light, brake, and battery lights will fade in and out, usually coming on when I start from a stop and just recently happened driving down the road normally. Sometime, rarely, the car will just shut off, no warning either. I'm concerned because this is a real driveability issue and I want to get it solved soon.

check your alternator belt and connections.

Belt is brand new <500 miles and connections are tight and good. I wish it was that easy. Maybe bad engine grounds?

could this be caused by a dying fuel pump or bad connections to the fuel pump?