#1 because it is a known unit . #4 bigger venturi same style . I ran a HP1000,1.56 venturi , on my 440 . Very happy, more power than my BG 825 #6b , a little bigger again . But if #4 shows improvement this will then show if annular is better for your motor . Then you will have to try them all again on the street / strip to confirm results .
Tex
New best ET 10.259@129.65 . New best MPH 130.32 Finally fitted a solid cam, stepped it up a bit more 3690lbs through the mufflers New World block 3780lbs 10.278@130.80 . Wowser 10.253@130.24 footbraking from 1500rpm Power by Tex's Automotive
