engine cutting out down track after in 3rd gear!

ok spec on setup. 360 .030 kb pistons 10.2to1 comp. run 93/110 oct 50/50 mix J heads ported with 2.02/1.60 hughes engines cam HTL4852s solid cam. 248 252 @ .050 .563/.572 106 lsa. air gap intake,Hooker super comp headers, carter race mec. fuel pump, holley street avenger 770 carb , pertonics flame thrower 3 bilet dizzy with rev limiter set at 6800 , TF727 race built with 3500 stall, 3.92 sure grip 28/10.5/15 MT slicks. problem I am having is after I shift into 3rd gear going down the 1/4 it starts to sputter, pop and stop pulling... dad said it looked like I lifted at end of track. not sure whats going on! looking for imput on what you all think. I found that the vac adv was pulling the timing up really high and that my fuel pressure was only at 6psi. I plugged the vac port on carb and unhooked the vac advance. recurved the dist to 34deg max. haven't changed the fuel pressure bc I need another regulator. could these things cause this? I haven't been able to get back to the track yet. and don't know when I will be able to. this is my daily driver lol. only ran 12.7@103 in a 67 notch cuda race weight 3300. what do yall think? im sure this combo should get me high 11's when running right and little better traction.