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backfire through throttle bodies

hey Austin, i'm the FNG on the forum. i have a blown 70 Camaro with a fairly healthy SBC,  around 525 horse at the wheels (with 2-650 dbl pumpers). had a blower on this car since the mid 80s( i know, i'm old) had the car almost 40 years. it now has a 6-71  w/dbl hump angle plug heads, and a .565 lift blower cam w/114 degree center line.  only 3 or 4 inches of vacuum. with the carbs it was dialed in really well but the carbs had no choke, so very temperamental in cooler weather. so decided to try the 1200 dual quad power adder system for better drivability. after wrestling with the iac settings for a while, it seems to work best between 13 and 20 steps. problem is it backfires through the throttle bodies and dies when getting back in the throttle after coasting for a corner or stopping at a stop sign. i know from my carb experience that this is normally  a lean condition and i would increase the accel pump shooters or pump cam  or maybe timing to take care of it. i'm just not sure which accel setting to try next to fix this  i have increased the shot across the ranges, which caused a bog, so i went down with setting now pops through the TB. am i in the right area (accel pump)  for this or should i be looking  more at timing. it has died in an intersection twice now ..don't feel like getting t-boned! any help would be definitely appreciated. thanks

Try disabling DFCO first.  Raise the enable temp to maximum.

if you back fired you may have blown out the back of the blower bas gasket known problem with super chargers I bought 10 of them when I installed my 871 causes a lean condition and loss of vacuum 114 lob sep you should be making more vac fitech likes at least 8 to 10  hg

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cool thanks, i will check that out. its been on there for a while. its very possible its blown out. i'll let you know.

thanks Austin, i will give that a shot too and let you know.