Weber carbs

Guest · Post by **Guest** » Tue Feb 13, 2007 3:37 pm

Hi All,

Just running through certain things on my new 72 911 ( 2.8 ). It has a pair of tripple choke webers fitted. I can't make out anything but numbers on the carbs and am trying to identify them. Am I right in assuming the triple choke webers fitted to 911's in place of MFi are usually the IDA version? Also, it doesn't appear to have any form of cold starting system. There isn't a manual choke and I can't see anywhere on the carbs for a choke cable. Anyone have an idea?
Also, it still has the original fuel filter in place, but with all but one (bottom)of the outlets blanked off or not being used. I was under the impression when carbs are fitted a different fuel filter (inline) is generally used. Can anyone shed any light.
Also I'm looking for a pair of air filter covers that offer protection from water as the ones fitted are of a sponge sandwich type and being located directly below the engine grill they get wet when it rains heavily. Anyone know where I may track some down.

Any help would be appreciated.

Adam

Lightweight_911 · Post by **Lightweight_911** » Tue Feb 13, 2007 6:43 pm

Have you got a shot of the engine that you can post here ?

It sounds like you may have ITG filters on the carbs - do they look like this ?

As for the Webers, they could be one of 4 models:

40 IDT's
40 IDA's
40 IDS's
or 46 IDA's

These carbs don't have any facility for a coldstart ('choke') system.

For air filtration you may want to consider K&N Watershields - the photo below shows one of these & also the location of the carb model number:

Berny · Post by **Berny** » Wed Feb 14, 2007 7:36 am

Hi Lightweight can you tel me the diffrence between IDT IDA and IDS 40s regards Berny.

Lightweight_911 · Post by **Lightweight_911** » Wed Feb 14, 2007 7:54 am

Berny -

Porsche originally used the IDA's to replace the Solexes for the 'S' models in early 1966 (the Webers were used on several Italian cars including the Lancia Aurelia V6's).

IDT's were a modified version of the IDA used on the 'T' models & incorporated different jetting & idle mixture screws with a different taper.

IDS's were introduced for the 'S' models sometime during 1968 (engine no. 960502) & incorporated an extra 'high speed enrichment' circuit - this apparently gave no increase in performance but was meant to be a safety feature to prevent destructive detonation at high revs.

Guest · Post by **Guest** » Wed Feb 14, 2007 8:55 am

They're nowhere near that smart looking. This is what they look like

Not very pretty.

Does anyone know if this will fit?
http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... L:RTQ:UK:1

davidppp · Post by **davidppp** » Wed Feb 14, 2007 9:24 am

hello, Adam.

It would be a guess as to whether that would fit: the Weber filter is different from the Zenith, and different between the 2.4 Carb and the 2.4 MFI T.

I'd look to put the MFI back, provided the heads have the holes for the injectors..

This would be a better long-term investment than sorting the carbs, and begin the process of putting the whole car back to stock appearance.

Kind regards
David

1972_911t · Post by **1972_911t** » Wed Feb 14, 2007 12:14 pm

You can buy the filters that Andy shows in his second pic for $159 for the pair.

http://www.motormeister.com/suz/carb_ac ... ilters.htm

Steve

Guest · Post by **Guest** » Wed Feb 14, 2007 12:20 pm

Excellent...thanks.

Lightweight_911 · Post by **Lightweight_911** » Wed Feb 14, 2007 1:42 pm

The first thing I would do is to remove/ditch the air conditioning system ! - I saved almost 100 lbs in weight by losing the air con on my 2.8 twin-plug car.

904GTS · Post by **904GTS** » Wed Feb 14, 2007 7:45 pm

From what I've heard Motormeister are a company to be avoided, a search on Pelicanparts forum will give you an idea of what they are like.

Also be very careful if there is a chance of water getting into the carbs, I know of an engine which hydraulic locked after being left out in a storm, bent rod a lots of other damage, you don't need a lot of water to fill a combustion chamber.

1972_911t · Post by **1972_911t** » Wed Feb 14, 2007 8:01 pm

From what I gather the problem with motormeister is the questionable quality of there engine rebuilds not new part supplies. When I was looking for a set of these filters motormeister was the best price I could find. Pelican parts do also sell these just for a bit more.

http://www.pelicanparts.com/cgi-bin/kse ... L-PP901526

Steve

Guest · Post by **Guest** » Wed Feb 14, 2007 11:02 pm

Ya, I checked out motormeister, but they rdidn't fill me with confidence when they said the postage would be $100, so I plan to order them from Pelican.