Crystal Report - Stored procedure

I wrote a SQl query that includes a function package. I also, filter the data for a specific date. The query runs in TOAD in about 3 minutes. But in crystal in runs for about 6 hours.

In crystal I used the Parameter Fields option to create a date parameter.

Question: Would creating a Stored Procedure for Startdate, Enddate speed up the processing time?

If the stored procedure is the answer, how do I write it for crystal to read it along with the query?

I appreciate all assistance. Thanks.