Does anyone know what size v band flange the precision 6765 uses? They claim 3" and i ordered a 3" flange and it doesnt work. its too big.

 

T3 housing I take it. Leading edge of your vband on the turbo is probably something like 3.1-3.2" in diameter instead being about 1/2 an inch bigger like an industry standard 3" vband that uses the larger flange/ clamp like you bought to use.

Take a look at this thread I posted in about this recently... should help you out. https://honda-tech.com/forums/forced-induction-16/precisions-new-vband-flange-2527590/