Weber set up sugestions please

[ariogul]

Hi 

i have schrick cam 284 - e12 head - and 40 dcoe webers with kn filters  and electric fuel pump . 
what should be the venturi idle jet f choke ..... sizes? 
thaks 

[Oldtimerfahrer]

Hi,

There are lots of posts on this topic in the general 2002 section, not here in the ti section which is more around the ti and less about tuning them. Generally speaking you can either follow whats written in the Weber books (which would give you a textbook starting point) or research more, but noone can give you any "golden" prescription even with displacement, compression ratio, cam etc. You are better off reviewing the posts in the general section, you might even find something close to your setup in the threads and ask questions there...I have 45s with 40 chokes so the information I have is useless.

Good luck,

Andrew 

[2002Scoob]

What Andrew said. There's only loose guidelines as a starting point, and you could end up 3-5 steps in either direction on any variable vs. another motor or setup, I find. 

 

You also win the award for most overkill brake-booster vacuum line  

 

And are all the rest of your AN-esque fittings actually fitted, or just kinda' sittin there? hard to tell, but your fuel lines look a bit suspect. 

Edited May 17, 2020 by 2002Scoob

[Jeff]

Weber sold 40mm DCOE carburetors to Alpina for a 2 liter engine under the designation 40 DCOE 88/89. I'm not sure what camshaft was used engine with this jetting, very likely a stock 264 degree camshaft to meet TUV requirements. 

 

I've also attached a PDF copy of the English Weber Tuning Manual

 

-Jeff 

 

Alpina 40 DCOE  88/89  2 liter jetting 

 

34mm      Choke Sizes

4.50         Auxiliary Venturi 

1.25         Main Jet 

.55 F8      Idle Jet   

F16          Emulsion Tube

2.40         Air Corrector Jet

0.60 F5    Starter Jet 

0.40          Accelerator Pump jet 

0.60          Accelerator Pump back Bleed

2.00          Needle Valve

 

WeberTuningManual (2).pdf

[2002Scoob]

240 airs! That's big for a not so big main jet. Interesting!

[Oldtimerfahrer]

Hi Jeff, 

I have an old scanned overview of Alpina jetting for A0-A3 setups from 1500 to 2002ti. It differs a bit from what you have...

For a normal 2-liter with a stock camshaft, it only has 7 parameters shown (?? are not on the german language table):

34mm      Choke Sizes

??         Axilliary Venturi

120         Main Jet 

50 F8      Idle Jet   

F16          Emulsion Tube

200         Air Corrector Jet

 ??   Starter Jet 

50          Accelerator Pump jet 

??         Accelerator Pump back Bleed

??          Needle Valve

They show 7,5 as the float level...but that is probably for the old brass style floats.

I will try to find a pdf, the one I have printed is pretty illegible.

Andrew

[2002Scoob]

Interesting again! @Oldtimerfahrer Please share if ya find a digital copy.  You're welcome to chime in and drop anything you find to the Brunhilde fat-ness thread, too 

 

If there's anything consistent about DCOE's, it's that they appear to be pretty inconsistent. Haha. I wonder what kinda of progression drillings they had...

 

I'm also on brass floats, and dropped their height down to 7.5 with a 50f9 and things started getting a bit lean with no way to reach the mains.

 

That's really interesting how they were running such lean air correctors... I find that a bit baffling. I just got back from a test-drive with the floats at 8.5, a 55f8, 125/180, and was mid-high 13's at WOT, and subsequently stepped back down to a 170 air corrector. And I'm still seeing 10's/11's on the wideband that I don't wanna see. 

 

 

Edited June 10, 2020 by 2002Scoob

[Oldtimerfahrer]

The lower spec Alpinas had 40dcoe carbs in Germany, but also the A3 came with a full tuv approval, despite 300 degree cam and 45's. The only real safety change for tuv being ventilated front disks....I have the alpina tuv compliance sheets showing what changes were done for the A3 to make it tuv compliant. When I registered my car in Germany, I went through all of the stuff with the tuv inspector and he dutifully typed it all into my registration document and even gave me a historical vehicle certificate...though my ti is not an Alpina tribute, I had a similar engine build.

Andrew

[2002Scoob]

Yep, I also used Alpina approval records for my DCOE's, although the approval I used (I forget which) states a HP limit of 112ps, I believe. Beyond that it requires larger tii spindles and brakes, if I remember correctly. 

 

Pretty sure I'm well north of that 112 number with my new build, but luckily I had a dyno-chart from my original motor from a few years before that which hit 112ps on the completely original motor with worn out valve guides and rings, which I used with my fresh build for approval.

 

Shhhh.... don't tell TUV!

[Chris_B]

So, what do you have now and why are you asking? Is there a problem with your current jetting? It is pretty much useless to ask what other people have because your situation is unique.