Attributes . 2-Circuit metering, 1.690 in. venturii, 2.000 in. throttle bore. Billet aluminum black anodized metering blocks. -8AN O-ringed inlet threads. Come standard with -8AN o-ring to -6AN male adapter and -8AN plug. Can be plumbed from either side. Holley Ultra Dominator race carburetors are for race applications only and are not designed or suggested for street use. Ultra Dominator carburetors do not provide attachment points for street transmissions, vacuum outlets or stock throttle linkage and cables. . Names