IDA vs IDT Webbers

[smestas]

I saw these Weber’s on eBay and was wondering if anyone can give me a quick overview of the differences between IDA and IDT specs.

I did try a search of "IDT+Weber" and found nothing.

eBay Link Click Here

[Bobboloo]

They're both the same thing. The IDT's were just jetted for the 2.0 T or L engines circa 68-69'. The IDA was not specificly jetted for a particular motor. They were found on several different early cars. They are completely interchangeable.

Bobby

[Bobboloo]

Here's the specs on the IDT 3C as delivered on a 68' T or L

venturi 27
pre-atomizer 4.5
main jet 110
air corr. 185
emul. F2
idle jet 50
pump jet 50
air bleed 110

These specs are only relevant if the carbs were pulled off the stock motor that they originally came on.

[smestas]

Thanks Bobboloo!

[911pcars]

Here's a minute detail difference between the two. The IDTs were installed on smog-controlled cars in 68-69. The idle mixture screws are not tapered like a typical mixture screw. They're more needle shaped with much less taper; the result is that the idle mixture changes drastically close to "seated", then doesn't change as much as it's backed out.

Sherwood Lee
http://members.rennlist.org/911pcars
Early 911S Registry

BTW, there's a quiz on the Registry BB regarding the Weber pic on the home page. Think you know Weber carbs? Take a look.

[Bobboloo]

I stand corrected. I didn't know that. Thanks Sherwood.

[jseel]

does anyone know where i can get a rebuild kit and more info on the idtp 3c/1 carbs? thanks a lot!

[Bobboloo]

Pelican has the rebuild kits. They were setup basically the same as the ones above and used on the 2.0 69T in the US. They were also used on the 2.2T's ROW but with different jetting.

[Zendalar]

Here is picture of different jettings on different engines. This was taken from www.mittelmotor.de catalog.