# Weber 40 carbs on 2.0 16v internal setup ? ? ? questions ? ? ?



## MicroCADDY (Jul 21, 2008)

OK I did a 2.0 16v swap with P&P on my mk1 Caddy then i carbed it. At the time weber 45s just after i finally got them tuned the engine went down & had to get rebuilt. As i was putting everything back together i ended up busting the carb in mounting. ( don't ask ) so i picked up a set of new Weber 40s well now i can't get these to tune for shyt.

*Here is my OLD 45 carbs setup*
170 air corrector
F16 emulsion tubes
145 main jet

55 F8 idle jet
36 Venturi

*NEW 40 carbs setup *
170 air corrector
F11 emulsion tubes
115 main jet

55 F8 idle jet
30 Venturi

running rich as hell. no back fire just carbs spitting & sputtering 



So what internals are you running with these carbs on 2.0 16v ?


----------



## candm (Apr 27, 2003)

MicroCADDY said:


> OK I did a 2.0 16v swap with P&P on my mk1 Caddy then i carbed it. At the time weber 45s just after i finally got them tuned the engine went down & had to get rebuilt. As i was putting everything back together i ended up busting the carb in mounting. ( don't ask ) so i picked up a set of new Weber 40s well now i can't get these to tune for shyt.
> 
> *Here is my OLD 45 carbs setup*
> 170 air corrector
> ...


im not sure why you are not running the 45s, but you will need at least a set of 34 chokes to run in those DCOE 40s. there is no point in changing any jetting until you have those in your carbs first. hopefully, your ignition and timing are sorted out but the chokes determine how much air moves through your motor and 30s are really small.


----------



## MicroCADDY (Jul 21, 2008)

I ended up snapping off one of the mounting lobes when mounting on my 45s. Was in a bind / time crunch & happen to get a new unused set of 40s off my buddy in less then 4 hours for $650.oo

Yeah i was looking into getting 36 venturi 

You thing 34s would be best ?


----------



## candm (Apr 27, 2003)

MicroCADDY said:


> I ended up snapping off one of the mounting lobes when mounting on my 45s. Was in a bind / time crunch & happen to get a new unused set of 40s off my buddy in less then 4 hours for $650.oo
> 
> Yeah i was looking into getting 36 venturi
> 
> You thing 34s would be best ?


I would get the 36s which are the biggest you can go in the 40s


----------



## candm (Apr 27, 2003)

MicroCADDY said:


> OK I did a 2.0 16v swap with P&P on my mk1 Caddy then i carbed it. At the time weber 45s just after i finally got them tuned the engine went down & had to get rebuilt. As i was putting everything back together i ended up busting the carb in mounting. ( don't ask ) so i picked up a set of new Weber 40s well now i can't get these to tune for shyt.
> 
> *Here is my OLD 45 carbs setup*
> 170 air corrector
> ...


new 40DCOE webers come with quite a different set of parts than what you have. somebody has changed a # of things, so im not thinking these could possibly be new. here is a list of what comes standard in new 40 webers:
chokes: 32 ( yours are 30 ). way too small
idle jet: 45F9 ( yours are 55F8 ). close to what you may need.
air corrector: 200 ( yours are 170 ) close to what you need.
emulsion tubes : F11 ( yours are F11 ) probably will work but a bit lean.


----------



## MicroCADDY (Jul 21, 2008)

candm said:


> new 40DCOE webers come with quite a different set of parts than what you have. somebody has changed a # of things, so im not thinking these could possibly be new. here is a list of what comes standard in new 40 webers:
> chokes: 32 ( yours are 30 ). way too small
> idle jet: 45F9 ( yours are 55F8 ). close to what you may need.
> air corrector: 200 ( yours are 170 ) close to what you need.
> emulsion tubes : F11 ( yours are F11 ) probably will work but a bit lean.



Well i bought them off my good buddy who bought them new. Never had fuel in them & never mounted. Now he may have been getting them ready for whatever he was going to run them on.

*THANKS for that info*


----------



## MicroCADDY (Jul 21, 2008)

1 thing i just found out. My floats was way way outta wack. Adjusted them & picking up 36mm chokes


----------



## candm (Apr 27, 2003)

MicroCADDY said:


> 1 thing i just found out. My floats was way way outta wack. Adjusted them & picking up 36mm chokes


you may have a bad ball and seat on the 1 carb on the left, however, you do not check the float level like you have pictured. you want to hold the top carb cover vertically with the floats hanging and and the metal tab on the floats just making contact with the ball. then, you measure from the float to the cover ( with the gasket in place ) ,and your measurement should be about 12mm, then, holding the cover so the floats drop, you measure again and should have about 26-27mm. you adjust the metal tabs on the floats to get your float levels set


----------



## MicroCADDY (Jul 21, 2008)

I know how you measure them & adjust them. both balls & springs are in good working order.

BUT i read on a could websites that they should be set at 8.5mm & 15mm 

What's the correct float settings for a spain Weber 40 DCOE ?


----------



## candm (Apr 27, 2003)

MicroCADDY said:


> I know how you measure them & adjust them. both balls & springs are in good working order.
> 
> BUT i read on a could websites that they should be set at 8.5mm & 15mm
> 
> What's the correct float settings for a spain Weber 40 DCOE ?


just what I said. the black plastic spansil float measurements are 12mm when measured with the gasket in place and the top cover held vertically so the floats are hanging down. when the metal tab just touches the ball, you measure between the cover and the float. the other measurement is taken by tilting the cover slightly so that the floats are hanging away from the cover, and at that point your measurement should be 26-27mm.
the #s you have are for the brass floats


----------



## MicroCADDY (Jul 21, 2008)

candm said:


> just what I said. the black plastic spansil float measurements are 12mm when measured with the gasket in place and the top cover held vertically so the floats are hanging down. when the metal tab just touches the ball, you measure between the cover and the float. the other measurement is taken by tilting the cover slightly so that the floats are hanging away from the cover, and at that point your measurement should be 26-27mm.
> the #s you have are for the brass floats


OK thanks. Readjusting now.

main jet size ? 


just looking to get things close as possible & then i will have a carb tuning guru run wideband on it & get them running like a beast


----------



## candm (Apr 27, 2003)

MicroCADDY said:


> OK thanks. Readjusting now.
> 
> main jet size ?
> 
> ...


wasn't it last time you took it to the " carb guru " that everything went downhill? I would invest in a wideband yourself as you can get 1 for under $200. make sure you have a flow meter to balance the carbs, and invest in the book, " how to build and powertune Weber and Dellorto carburetors. good luck


----------



## MicroCADDY (Jul 21, 2008)

Yeah last time the " guru " had to come to my place to tune them & didn't work for him. but i have recently talked to him & can come to him. 

BTW it is running a bit better since i adjusted them floats to the specs you suggested.

WIDEBAND is on my list for sure & i already have a syncrometter


----------



## FLiGLi84 (Dec 5, 2006)

I have some 40mm Dellortos and I need yo adjust the floats. Car runs but running out of fuel.... Someone told me the floats or the adjustment on the accelerator pumps are at different lengths!! I am looking for someone near Houston or close to ship them for rebuild and adjustments. Any ideas???


----------

