Heat riser/ choke question

When I changed my 318 from the stock 2bbl and intake to the 4bbl 340 intake, I used the intake gasket that blocked off the heat riser for whatever reason. Saw a fb discussion about heat risers and up to this point I had no idea it was used for the choke and fast idle on it, ever since then the electric choke wants to stay in fast idle for a very long time, even on startup after being driven. That being said, is there a way to adjust fast idle and when it returns to regular idle without the use of the heat riser? Carb is a 600 holley street warrior vacuum, first carb i've owned with an electric choke minus the stock 2bbl. TIA