There is no 750 in the Thunder series only 650 and 800. the thunder series would be a better choice for a street car wit hthe tunable secondary air door.
Dwayne Porter ran a performer series in a dyno test on his stocker 383 , it's in the tech archive , it was a turd , he swapped on the carter version of the same carb and it ran so much better , Ebrock has the carb made to their specs and it would appear that it is a different internal calibration than the carter version.
I have one of the old carter versions , great carb , I HAD the ebrock
