[peterpjb]

Originally Posted by Gaz64

The photos are DCOEs, which at the time, the largest would have been 48mm, 50s and 55s came later.
DCO 3 carbs are completely different in many ways, the mounting flange is the first major difference, and hence the carbs don't interchange.

DCO 3 and DCO 4 are Ferrari 58mm carbs, and very rare.

If Carroll did run DCO 3 58mm carbs, the manifold would've had to have the different flange mounting.

Note on Page 9, where the statement of the carb rarity, and the consequent option of 48 IDA downdraft carbs.

https://historicdb.fia.com/sites/def...9_group_gt.pdf

page 9 is the addition for Sebring ‘63 where the SAI Cars raced the first time with Weber 48 IDM