Conference vmsnet::car$note:carbuffs

    Two Questions:
    
    Does anyone make a conversion kit to change from points to a magnetic
    trigger, without having to do any major mods to the distributor?
    
    Also, what is the correct vacuum port on a Holly double pumper to hook
    the vacuum advance line up to?  The line is currently connected to a
    port located up near the side of the front bowl.  There is another port
    down near the throttle plate that is plugged off.  I thought this was
    supposed to be the one for the vacuum advance.  Is this currently
    hooked up wrong?
    
    Dave
    

    The easiest way to convert is to replace with a good bone yard non
    computer controlled HEI type dist.I my self am using a stock GM point
    distributor with accel components and have never had any problem.
    The current set of points,rotor and cap have been running for
    three years and every time I check the dwell it is right on the money!!
    If you choose the HEI you must run a new 12v ingition on wire to eliminate
    the resistered wire which feeds the + on the coil now.
    
    The vacum port at the base is all the time vacuum. The port above the
    base in most cases is the timed port which is for vacuum advance on
    holleys. 
                                                Jack

>    Also, what is the correct vacuum port on a Holly double pumper to hook
>    the vacuum advance line up to?  The line is currently connected to a
>    port located up near the side of the front bowl.  There is another port
>    down near the throttle plate that is plugged off.  I thought this was
>    supposed to be the one for the vacuum advance.  Is this currently
>

It depends on the vintage of the carb as to where the ported (timed) and 
manifold vacuum ports are located.

On my really old Holly, the manifold vacuum port is on the side of the 
metering block.  On the newer versions, it's on the throttle body.  On even 
newer versions it's back towards the center of the carb on the throttle 
body.

Hold your finger over the port while the engine's idling.  If there's 
vacuum, it's manifold vacuum.  If there's none until you rev the engine, 
it's timed vacuum.

Most General Motors engines want manifold vacuum at the vacuum advance.

    I used a Pertronix conversion when I went from points to hall cell.
    Quick and easy. No mods to anything. Cost about $65.
    
    Chris