Edelbrock Air Gap on Magnum 318 Problems
Wow, 6 months later! lol I understand what happens with the cars when you're building a house though. Time flies!
I'm actually experiencing a similar issue with a Holley 600 DP carb on a 340 with a Holley Strip Dominator Intake (Similar to your M1) and a 4-speed. I'm definitely interested in what you do to cure the stumble.
A 650 on a 318 is definitely a lot of carb, but tuning can always be done. Good luck!
-Mike