Is anyone familiar with A-25 Champion spark plugs ? I ran across a set of 4, but can't find any info on them. Hope they are a good plug for a model T
I run them in my speedster's Rajo head. They work great for me.
Word of warning; do not screw the terminal top down too tight. When you go to take it off you can unscrew the top of the electrode from it's connection inside the plug and they never seem to work the same after. Been there, done that.
A-25 plugs can be either a single unit or 3 piece construction like X plugs depending when they were made. Either will work just fine. The older 3 piece plugs came in an X style insulator or the later ribbed insulator style. Most were labeled with
X and A-25.
These are newer plugs, not 3 piece. Thanks for the info guys.
Not to speak for Mark, but I've read about the problem he spoke of, and the problem is that if you're not careful as he says, the center electrode can actually come loose from the porcelain on the plugs that are not designed to come apart.
The separating electrode seems to be a common problem with the A-25 plugs. I've experienced the same thing with Autolite 3095, but only once.
The 25 have a screw connection that might have been glued in place but with a little force they of course thread off the same direction as the terminal nut.