An Edelbrock 500 CFM with electric choke works great, but wont bolt to your intake. There may be an adapter available, or you can use a 57 up or Blue Thunder intake. Always mount an Edelbrock on an insulator at least 1/2 inch. One thing to remember, the distributor design changed in 57. If you change the carburetor on a 56 or older Y block, to make it run its best, you MUST change the distributor to a 57 or newer.