Carb cfm with ported heads?

I can’t say for sure based on a few factors starting with I haven’t been there and done that.

Generally speaking, a bigger carb can be harder to tune because of the reduced signal to the carb because of the bigger throttle bores, cam size and timing events, numerically low gear ratio, etc....

Your engine has increased in size thus reducing what would be a huge carb on a 318 down to something closer to what it could use.

Depending on many factors it may very well be a non issue going to a 950. But as I said before have not been there and done that.

I hesitate to say, “Go for it!” I don’t want to suggest something that I’m not confident on.