Hot 318, carb choices.

If your 500 is rich,your not going to like a 750.
Sounds like someone has the 500 way out of wack.
Your car should run good with a 600-650 cfm carb.
You just need to decide which brand to go with.
I've had good luck with Ede carbs. My choice would be a Ede 600
for that hot little teen.