600-650 cfm is enough for that motor, unless you constantly ride above 5500 rpm. The formula for carb size is on this page, look in the paragraph: Size
TuningMadeEasy
I recommend the Summit carb. I have it on both my Pantera and my Longchamp. Best carbs I've ever had, super throttle response. And no fumes.
PANTERA INTERNATIONAL
A DE TOMASO CAR CLUB
Presents the De Tomaso Forums
The On-Line Meeting Place for De Tomaso Owners and Enthusiasts From Around the World
Clicking on the banner will take you to the sponsor's website.