Webers & Spark Plug life

[Rick Parker]

My plugs are for the most part consistently dark, indicating that the mixture is rich. My jetting package is close to what others seem to be using. What plug life are those with Webers seeing AND are you able to get a good plug color with good drivability? How often are you guys changing your plugs? They seem to like a rich setting. It runs good.

[Tom Howland]

I'm still tuning after 1 year. Plugs are black. I get about 300 miles on the plugs. I've got a blast cabinet so I can clean them easily. I am making progress on the tune though. I don't spend that much time tuning. Using an A/F meter which I couldn't do without. The mains are working well. Stumble in transition. And too rich in Idle. Thats were the black comes from. Thinking of drilling out a 60 Idle jet to 62 or 63. I'm at 65 now. I've been through all the holder sizes. The stumble at transition I'm hoping is a similar problem like "big deuce" had. That I can fix. Right now I'm working on the heat soak problem boiling the gas down the venturis. Been changing the oil a lot. I've got the 1/2 inch spacers under the carbs but that has not helped. This weekend I'm putting in another relay, switch, and 10 minute timer to the radiator fan. I'm hoping the air circulation for 10 minutes will keep the temp. under the boiling point and not deplete the battery.

[Gaz64]

Rick,

I have run two cars of mine now, one with quad 44 idfs and the other with twin 45 dcoes with a data logger wideband O2 sensor, carb mounted tps, map sensor, rpm signal etc.
After a 10 minute drive of various loads, I can look at the logged file at leisure and adjust as necessary.
It is time consuming, and a lot of trial and error, but you can sneak up on the tune to get near EFI quality.
My plugs average out at a dark outer shell with the earth strap colour change mid point along the strap.
The insulator shows no sign of overheating, I get about 5000km out of my plugs before I decide the edges aren't sharp enough, then it's time for a plug change.

[lemans24]

38 degrees full advance on the timing fixed my fuel boiling issues. When i shut it down I still turn the electric pump off just until it starts to stumble just to be on the safe side.

[paulmartin]

hello rick , i just ran NGK R5671A-7
gap them at .42
they are a hotter, racing plug and run clean , the difference is amazing.!
hope this helps , cheers paul