I am designing a downdraft linkage for Webers on the E3s and E9s. It will be another month or so before production and I will announce availability as soon as I can. In the mean time, can someone tell me what the circled lever in this pic is for? It seems to activate some kind of switch I believe. Is it necessary?
Downdraft Linkage System question
- Thread starter halboyles
- Start date
It is for a vacuum operated diaphragm to slow throttle return when decelerating, controlled by the speed relay and a dashpot on the firewall. Most no longer work after 50 years.
and used to rev the car when tuning the carbs 
So, it sounds like it is unnecessary for most users.
Well, at least this vestigial part has some purpose!and used to rev the car when tuning the carbs
Most of these diaphragms are frozen and don’t move anyway
jmackro
Well-Known Member
Hal:
The arm & tab for the diaphragm probably isn't necessary. I have Webers on my car and removed that diaphragm many years ago; it works fine without it. Perhaps they were more critical with the original Zenith carburetors.
I have been monitoring you website from time to time, checking whether your improved linkage was available yet. Glad to hear that it is getting close.
The arm & tab for the diaphragm probably isn't necessary. I have Webers on my car and removed that diaphragm many years ago; it works fine without it. Perhaps they were more critical with the original Zenith carburetors.
I have been monitoring you website from time to time, checking whether your improved linkage was available yet. Glad to hear that it is getting close.
Jay, they were a rudimentary attempt at smog reduction.