My 1969 e type OTS is fitted with triple 2” HD SU carburetors.
I can find very little information on the slow run volume valve. Is there a methodology in setting this up.
Right now the rear carb slow running stop is hitting the carb body, any movement on setting screw increases the RPM above 900rpm.
I can lower the RPM down by screwing in the Slow Running Volume Valve, this then allows me to take the stop off the carb body and adjust the low idle in the conventional way using the low idle setting screws.
it seems to have very little effect on the higher RPM running.
Any information on this would be helpful in tuning this valve.

 

Do you have the small (paper) handbook that comes with the car? If not, you can get it on Fleabay easy enough. The instructions in there for setting up the carbs is excellent.
Here's an ebay link https://www.googleadservices.com/pag...gQIARBz&adurl=
My '69 4.2 is a brown book, but SU set up instructions are the same