Wednesday, May 9, 2012


So many things to talk about it's been hard to pick one. You readers have been quiet. That's good, that means you have been outside. But I do need some input. What would you like to talk about? I have been struggling to pick one topic each day this past week.

Today I chose our friend Sparky. Sparky makes things go and he has for over 100 years now. I am talking about spark plugs. Since I decided to replace the ones in the Buick, I got to thinking how much longer they last than when I was a kid. They were lucky to last 10,000 miles in 1966. This set had 135,000 miles on them and 5 years of weathering on them but they didn't look too worn.

They gauged about .005 inch wider than factory specs. That is not much wear after all those sparks!
1500 RPM divided by 6 cylinders, and... that is a lot of lightning strikes inside that cylinder. The plugs were $9 so I thought I better change wires while we're at it. They looked and felt new but they have carried a ton of voltage over 5 years. Ever see an old car or truck or tractor engine running at night and you could see the wires light up? I don't want that after the effort of changing the plugs.

On the Rendezvous, you have to unbolt the engine mount and pry the engine as far as it will pry to get to the back 3 cylinders. The flexible exhaust connector won't let you pry the engine any farther. It's a nightmare under there. Don't complain when you get your shop bill, believe me. It's worth every dollar they charge in my book.

About the only way these plugs can fail is if the resistor inside of them burns in two pieces. The tip is made of titanium and is about indestructable so I imagine many if not most of these engines go to their grave with the original plugs in them.

The engine fired quicker than ever and I could feel the difference. It runs smoother and you can feel it from the moment you start right into high gear and road speed. I am sure I picked up one or two more miles per gallon.

The Dodge has 100,000 on its plugs again so I might change them. They are much easier to change because of the size of the engine compartment. It runs so much smoother after I cleaned the battery terminals it isn't funny. These engines are so sensitive, just a volt or two makes a big difference in performance.

The best thing about the old Delco HEI distributor was we didn't have to gap and replace ignition points any longer. It's amazing what these systems do today. A friend told me we are all driving what Indy or NASCAR had in the 60's, about one horsepower per cubic inch. That's a pretty good analysis.



  1. Far as I know mine are still original in the 97 Blazer with 145,000 km . If I ever do change them I don't want to be the one working in that cramped space. Even my old vehicles seem to go a long time on spark plugs now . Today's gas maybe burns cleaner?

  2. Like your picture.


  3. Yes, today's fuel is pretty clean, Ralph. The 10%, soon to be 15% ethanol in American fuel cleans everything out! I wonder how much wear you have on those? This engine just got a little sluggish so I thought it was time for new plugs. What a difference! It really runs like new. Anonymous, Sparky has been around a LONG time!