A blown power valve rarely even happened when there was no power
valve protection, I think since the early 90s holley went ahead and modded carbs so they would not blow a power valve, I never had
a blown power valve probably lucky, because in younger days I had carbs and timing that were not even right and had backfires.
I don't see anything wrong with running a double pumper square bore
carb on the street but on something with a strong vacuum pull at
idle like a ZZ4 or even the hot cam, it would really be pulling in the
fuel off the idle thats set up for a low vacuum race cam. Someone
that has had a Q-jet thats set up to be a good street carb slaps a
double pumper on there street cam, they will think all holleys are
fuel drinking aholics. I have had four Q-jets 72-350,73-454, 78-350 vette 78 454
pickup and a 69 350 pickup, none of them were quadra bogs, but i'm sure
if it was goofed up something had gone wrong with it like anything else
it could bog on the secondary. the 73,78 vette 78 pickup I bought new
none of them came from the factory quadra bogging. But I do love to
tell a true Q-jet man his carb is a quadra bogger if I know its getting under his skin. Yrs ago I had friends that had lunati cams so I
would refer to there cam as a Lunitic cam I always used a Chevy,
Crane or Crower cam so they would call my cams CRAP cams
I know TimH will be ordering a set of Vortech heads probably next week.