So my 1970 impala 350 with edelbrock 1406 carburetor air filter is 14x2. i want to get a longer air cleaner stud and put in a 14x3. I am not sure it will still fit under the hood. Does anyone know the answer?
You can easily put a 14x4 filter under the hood as you have a small block and the Edelbrock-Carter AVS carb is the same thickness as a Rochester. Your car was offered with a big block that sits two inches higher than a small block (and two inches longer and nearly three and a quarter inches wider; which is why they are called a BIG block). Just doing simple math you know it will fit.
You could probably close the hood on a 14x6 severe duty air cleaner off of a pick-up truck (designed for construction sites or driving on dirt roads), but I would check it before slamming the hood.