HELP 388cu in with issue?

388 cu in sbc approx 450 hp

I was just thinking maybe the cam wasnt degreed in correctly or the msd box in a clunker even though its new.
Tried timing at
38
40
45
48
50
52
and the car ran same et's
Dead hooks best 60ft was 1.70


1963 nova 2800 lbs
cast vortec heads
eagle crank
10.5 compression
.525 lify hyd .282 dur
770 street avenger 74front w pv 77 rear
dual plane intake
turbo 350
2800 conv
4.86 rear- w/spool 12 inch slicks
msd 6al pro billet dist

Eigth mile or quarter
car has been 7.85 at 86 in the eigth
12.33 at 106 in quarter


plugs look good
changed jets 2 steps and gained a lil mph plugs are right - jetting good

there is no need to set the total timming past 40 less you want to blow the engine up were is the curve at ?