250 GTE with weber 40DCZ ?

Hello.
We are Restoring a 62' GTE and the Webers are 40 DCZ carburetors. Are these uncommon? Rare?
The only litterateur I read only ever mentions the DCS or DCL.
Kind regards, Robert

 

What is the serial number?

1st series and early 2nd series cars had 40DCZ carbs. In summer of 1962 - somewhere around serial number 34xx-35xx - they changed for 36DCS (?). Not sure about exact types as I cannot tell them apart on photos.

My early 2nd series car (3197) has a set of tipo 40DCZ6.

Cheers, Kare

 

Hello Kare.
Thank you for the reply. The Chassis is 3433
Best, Robert

 

on a related topic of the 36 vs 40, what is the difference between the two carbs?

 

Ed The throttle bores are 40 mm on one and 36 mm on the other. Both carbs, when used on street 250's, had 27 mm chokes. They 'downsized" from the 40 mm bores to assure higher air velocities for better response and mixtures without giving up total air flow through the 27 mm chokes. A simple explanation for a more complicated situation.

 

great explanation - i like simple

 

Perfect opportunity for a further question!

250GT Lussos use 36mm carbs (DCS?). Some of them - maybe 10..15 cars or so - have 40mm carbs (DCZ?), and many of those have been documented having these for quite a while, so they might very well be original. With all your experience can you perhaps estimate would this change the character of the engine, so were bigger carbs maybe an option for enhanced performance or were they just using up the remaining 40s found on their shelves?

Cheers, Kare

 

Kare: By #3467, 250 street engines had switched to 36 DCS carbs. ALL the Lusso's for which I have Build Sheets (including the Prototype) were constructed with 36 DCS carbs. Based upon the fact that the 250's had been using these carbs for some time, I believe that all Lusso's were built with 36 DCS units. I believe the change was solely due to costs and the 36 mm unit giving better overall performance, especially in the lower rpm ranges.

 

Makes perfect sense. I've also noticed that Weber serial numbers rise through production but in the end numbers get completely random. For me this clearly indicates they were cleaning the shelves.