QuestionI want to install a pair of used Weber DGAV's that I rebuilt on my 76 TR6. I have Pat Braden's book "Weber Carburetors" which took care of the carb rebuilding. I'm looking for installation instructions for putting the carbs on the car. I have the leakage and intakes which is no problem, but don't know what to do with the vacuum hoses etc. Do you know of any literature available concerning the hoses?
AnswerHi Terry,
I don't have any info on the vacuum connections of that carburetor system but I can tell you some of the info on what BLM did with the TR-6.
First you need to look at the distributor to see if it has a vacuum advance unit, a vacuum retard unit or both. Some TR-6 cars came with both units on the one distributor as BLM tried to meet US emission standards, then they plugged the retard unit and only used the advance unit even though the car came with both on the distributor.
Any time you modify an engine you alter the needed advance curve of ignition. Generally if you have a vacuum advance unit, you need to connect it to "Ported Vacuum" (vacuum picked up on the carburetor flange that only had vacuum when the throttle is opened)
If you have a vacuum retard unit on your distributor you need to connect it to "Straight Manifold Vacuum"
If your carburetor/s does not have a ported vacuum port and you have a vacuum advance unit on your distributor I would drill the base of the carburetor and install a tube for "Ported Vacuum" or get a distributor with a vacuum retard unit on it.
It takes some equipment like a distributor machine and/or a Dyno and someone who is sharp on advance curves to get it to the best it can be.
But just for normal street use you can probably get away with just using a standard Triumph advance unit distributor with ported vacuum or a vacuum retard distributor with manifold vacuum.
Most of the other components in the system were thermovalves and delay valves in the vacuum lines for emission standards.
That is the best I can add.
Howard
