interesting Weber 32/36 tuning setup

[hpsenicka]

As I slowly work my way through various systems on my '73 2002I am finding a variety of curious things that need attention.

The most unusual one so far if the way the carb has been set up.

The PO had somehow managed to set up the Weber 32/36 with an open vacuum port! The vacuum port on the intake manifold at the base of the carb (where you would expect the vacuum advance to be attached) had a one inch piece of tube slipped over the fitting.... but it is not plugged, and goes nowhere!

The car will not idle if I put a cap on this fitting... so I am presuming I need to reset the "best lean idle" mixture and idle speed according to the normal adjustment procedure after I cap the fitting.

Before I change anything ... is there any legitimate reason for the carb to be set up this way?

While I am at it, would it be advisable to re-route the vacuum line for the dizzy to this location? The dizzy vacuum line is currently attached to a manifold fitting closer to the #3 and #4 cylinders.

[peteinjp]

While I am at it, would it be advisable to re-route the vacuum line for the dizzy to this location? The dizzy vacuum line is currently attached to a manifold fitting closer to the #3 and #4 cylinders.

when I had a 32/36 the port at the base ran to the distributor vac unit. I'd give it a shot. It should affect the idle as that is the highest vaccume is it not?

[winstontj]

Take a look at the base settings per the Weber manual and also take a look at CD's settings. Honestly I didn't notice any difference between the two in terms of performance or that flat spot they all talk about. I did however notice a difference in fuel economy - it got a little better when tuned properly (to CD's specs even with the larger secondary).

As for the vacuum advance - it's gotta be at the base of the carb not on the manifold. I don't really know the *science* of why but it just does. It has more to do with vacuum reading as you open the throttle or something but you've gotta put the advance there, NOT on the manifold. Plug everything else up, put your advance in the right place, time your motor with a timing light, set the carb to base specs and you should be good to go. At least if nothing else you'll have a great platform to start with.

[oh2fly]

You need to know if your distributor is vacuum advance or retard. If advance, the port you need is the bigger one above the throttle plate that has no vacuum at idle. If it's a retard unit, use either the port below the throttle plate or one in the intake runner. If you attach a hose to distributor and apply vacuum, if the engine speeds up, it's advance. If it slows down, it's retard. If it does nothing, reach for your wallet, the diaphragm is shot.

[mikem]

The advance hose to teh distributor should attach to the vacuum port on the CARB, near it's base.

Also, check your distributor's vacuum advance module to see if it holds a vacuum. If not, then the diaphragm is shot and it is just one big vacuum leak.