Really, the intake port is comprised of all the space from the carb throttle plates to the valve seat. If you look at tit that way, you can see how important intake choice is. In terms of Indys, the SR-EZ heads "as cast" have the same intake port as std SRs. The exh port was placed in the stock head's location to make the installation in A bodies running a B block easier. Hence the "EZ" monicker. There are a ton of questions before choosing a head package. After that is settled, the intake choice has pretty much already been done by the process. What is the chassis? What headers do you have or want? What cubic inch? What is the desired HP/TQ/ performance results? What kind of rpm range? What kind of driving will it be doing? How much money do you have to spend on the entire deal? Pump or race fuel? What cam and gearing do you have? You will need to have the convertor adjusted or replaced I'd bet when making a big engine change, so budget for it. Same with carburetor choice. I can tell you, if street driving on a 440 RB engine is the answer, there are much less expensive options than Indys. It takes about 500 hp to put a typical radial tire 3.91 auto E body into the high 11s. With 4.10s or more gears, and slicks, it will run low 11s. Iron heads with mid level porting can make that on pump fuel and a hydraulic cam can make that much power. Cheaper aluminum ones can make 500-600hp even easier with the right matching parts. Indy SRs and SREZs will move enough air to make that with no mods. With mods, and the right matching parts, I know of some that make just shy of 750hp on VP C-12 fuel, single carb, N/A. But the higher the number, and smaller the engine displacement, the less "usable" power there is. Meaning they get very peaky and need RPM to make those numbers.
