Well, its not an adaptor there.......the top of the manifold itself are reworked. Directional blades to get even distribution, internal cooling lines for watercooling. The water/meth injecion system is DIY, by Cooling Mist pump & nozzle, adjustable hobbs switch, and a reworked old school Edelbrock boost controller.
...and the picture lies a little... hole stuff coming lower, it was just a checking for space against brake booster, laid on top of the carb....
