Weber DCOE45 152 45DCOE progression circuit modification

[alfettaparts]

I remember I had similar issues running 45mm dellortos. I was able to open one of the progression hole a little rather than drill another hole. Also spent ages experimenting with the airbleed holes on the idle jets using tip drills and solder. Once I got them right I bought a set of jets drilled them and left them alone. The motor ticked over at about 700 rpm and behaved pretty well in the progression phase given that it was heavily modified with some crazy duration cams.

[maxbg]

Apologies for digging up old threads.... I have a weber 45DCOE 152 which has a higher air flow in the 4th cylinder.

Pls see the youtube clip.

YouTube - Weber Carb balancing

The question is whether I can use the 152's Air Bypass bleed screw to equalize the air flow?

[Gordon Raymond]

Impressive guys! I've been restoring Weber units since the '60's and have seen few discussions as on point as this one. I avoid the Spanish Webers largely because of what has been discussed here, lack of flexibility for many Alfa applications without additional labor. Gron Perry will agree with this! Even the late Italian 138 /139 series are more tune - able, without additional progression holes or modified (grooved) throttle plates. The problem for the Weber restoration fellow like me, is cost that needs to be passed on to the customer. When I have to R&R throttle plates, mill a groove in them, or drill precise additional progression holes, that takes time, and costs money. My customers are better off with a set of 40DCOE2's or 45DCOE9's to begin with, even though more "used". Your discussion IS right on the money, and I am pleased you all have spent the time to discuss this problem. As mentioned, some of the newest "stuff" from WEBCON addresses these issues, and will hopefully return us the Webers we want that are flexible in application.

[maxbg]

YouTube - Weber DCOE Modification