Of course they do Tango -
Chevrolet 262-400 Small-Block V8
PERFORMER RPM Q-JET (1500-6500 rpm)
Designed for 1955-86 262-400 c.i.d. Chevy V8s for spread-bore (Q-Jet) or square-bore carbs. Delivers maximum power and a broad torque curve for high-performance street. Carb pad will accept square-bore carbs without adapters. Performer RPM Q-Jet has same provisions as #7101 (see above). Will not fit under stock Corvette hood.
The Weiand Stealth is square flange only, however; the 8004 "Avenger" is a dual plane spread bore mainfold.