Question on holley 4150

i might of miss read your post,is 13.8 your crus AF than thats not bad....my book is old and iam not shure what pv is in a 750 hp, i would think a 6.5..would need the part number to look it up....to find the right pv for your combo...your going to have to drive around with a vacuum gauge and see what your cruz vacuum is,then get a pv slightly under that...........lets say your cruz vac is 10 to 12,then you well need to start with a 8.5 and go from there.....i hope this helps.....good luck