On the dyno... your "legacy" CFS 850 annular made close to 10 HP and a similar # increase in torque over the GC in 1.425/downleg config. That's what got me interested in trying the 1.562/annular config.

I couldn't get the 1.562/annular to run any quicker or faster on the track than the 1.425/downleg, and it didn't run nearly as nice on the street, either. I didn't have the patience, knowledge or opportunity to try it again before selling the annular boosters w/ the silver 1.590" sleeves. I do still have the black sleeves & downleg boosters, but will likely offer those for sale, too.

Speaking of the silver sleeves... when I bench-tested a bunch of carb bodies & GC sleeve & booster configs -- even using downleg boosters -- the silver 1.590" sleeve flowed LESS than the black 1.562" by 10-15 CFM IIRC, in addition to having less booster draw. My hypothesis is the transition into the large(r) venturi with the Claw / Demon entry form is too abrupt, which is why the venturi size increase doesn't translate into any flow increase.

I'd have to dig back into "the archives", but at some point BG upped the "model" of the 1.562/annular config to something "bigger", but I don't remember what at this point. BG's wet flow test #s they used to put on the back of the original Gold & Silver Claw brochures (I still have one of each) don't correlate to anything that makes sense to me, even today. Between BG and Holley, the "model" stopped relating to anything tied to venturi/booster/throttle size config years ago...