Upon discovering that Zenith carbs were not correct for our engine, I started checking the availability and price of Weber IDTP. I soon discovered a very subtle distinction in a pair I saw for sale. If I have this right, the 914-6 part number adds a “1” after IDTP, whereas the 911T does not. So
914-6 70-76
- 40 IDTP 13 C1 – 901.108.115.00
- 40 IDTP 13 C – 901.108.126.01
911T 69-
- 40 IDTP 3 C1 (left 911) – 901.108.118.01
- 40 IDTP 3 C (right 911) – 901.108.118.01
The distinctions, like the model number, are quite subtle.
The Webers themselves look identical from IDTP to IDTP1, the only real difference is the location of the main fuel jet installation. The main fuel jet location for the middle barrel is towards the front of the car so for 914/6 the location of the main fuel jet is relocated from that of the 911, nothing more that that and a part number difference.
Paul Abbot from Performance Oriented
