Weber IDA/IDT Question

[Mikey83835]

Differences? I have the Haynes Weber manual and they do not address the issue as far as I can tell, other than to show slightly different jet sizes in the reference tables, and that the IDA is for a 911 and the IDT is for a 911T,

Thanks, Mike

[Grady Clay]

Try this:

Weber Carbs Diff Between IDA IDT IDTP

Best,
Grady

[Mikey83835]

Thanks Grady

[1QuickS]

IDT's and IDTP's used a 1.40 mm idle air bleed vs. 1.10 mm for IDA/IDS/IDAP carbs and 0.80 for 46mm IDA's. This air bleed serves the same purpose as the air correction jet for the main circuit. Most of the Weber carbs (and PMO carbs) provide for changing this air bleed but it is pressed in on the three barrel carbs.

IDT's also have an altered progression circuit from that of IDA/IDS/IDAP carbs being a leaner progression.

The progression correctors may be rather easily modified into tuneable correctors. Other components of the IDT/IDTP carbs are easily swapped out.

See details of the above progression circuit hole patterns and the tuneable air bleed modification on my web site.

Cheers,
Paul Abbott
Performance Oriented