The performer has 318 sized ports and is ideal for that engine. If you had a 340 or 360 you would probably want to gasket match and blend a bit but it will bolt on and work fine as-is. The performer is also one of the few aftermarket intakes that will allow you to bolt up a factory AC compressor in the stock location.
That is 100 percent why I used one on my old 340. A/C and easy to port is was almost like the 340 one night wise etc.
Was a better to choosecthag than others.