<VV> Re: main jet vs idle, Plug fouling. Longish

[NicolCS at aol.com]

Your saga reminds me of why I installed and MSD-5 (multiple sparks below 
3000rpm) on my '67.  It helped, but the final remedy was to locate the vacuum leak 
(throttle shaft).  I used to have a 308-GT4 that just loved to foul plugs at 
idle.  Installation of MSD-6 boxes transformed that car from a plug fouler to 
an "idle forever" motor.  Of course, your car should run perfectly without 
such nonsense but...  

Have you swapped carburetors from side to side?  If the problem stays with 
the carb, it's a carb issue.  If not, it's an engine issue.  Do you have a 
spare, known good, distrubutor (with cap and wires)?   If the problem remains with 
a swapped ignition system, you can eliminate that as the source of the 
problem. Have you tried looking at the engine in the dark of night?  Sometimes you 
can find a HV arc-over on the coil tower or on a plug wire that way.  

BTW, re your engine scope: I remember learning that the bright dot on the 
rising coil voltage trace is the rotor gap.  It should be about 5KV, AFAIR. Also, 
is the firing line a smooth, drooping horizontal, line?  If it's erratic, 
that's said to be cylinder turbulance from a leaky or sticky valve and that can 
disturb the ignition process.

This is fun but I'm glad that it's your car this time <GGG>  Is this 
something like an initiation rite?
Craig Nicol