What has caused you so much blower surge, vacuum leak?

making 10" vacuum bud.. no leaks just a big azz high helix retrofit blower... and big cams on 565cid with big heads... need to do some blade reworking on the carbs... if I run idle up a bit surge is less dramatic, but goes too hard into gear

What is meant by high helix? Is that the design of the rotors?

What are you swapping out for? Just curious.

High helix is a billet rotor that as more twist to it than a conventional 14:71 rotor and the retrofit is the delta opening on the bottom tha has been pushed forward to the furthest point possible.. the opening is cut into the front gearcase... this is why the blower is so far back on the manifold... 12 lbs of boost @ 6% underdrive... there are many factors that influence boost, big heads, big cams, cam timing etc

was going to go to 5 liter whipples but it didn't pan out

I see, I questioned the builder why not go to the whipples instead of 14-71s on mine, we ended up with 14-71s, that;s why I asked. (or PSI, but then he told me what they cost....)

these are no normal 14:71 ... I used to run the same type of blower on my BB funny car

Yes, I figured with your description, a nice boost # for running it underdriven, I know there's more to it than that. what is your pulley ratio? Crank to Blower?

Who does your engines? You I presume? (I see AK Racing in your boat descrip).

59 bottom 63 top 8mm drive

you are correct in your presumption lol... I've done one or two in the past I do mostly custom work where I can take my time, no rushing..
it takes about 100 hours of real time from start to dyno ready completion for an 1100 like mine... tons of meticulous fitting and trial assembly etc...