I need help with plug reading.

I have almost 1000 miles on the 250 now. She's running good ftmp. Choke is sticky from 3/4 to full closed. I pulled these plugs today after a good highway run of around 15 miles. I could put all I know about spark plugs and reading them on one of those mini post-it notes so I could use some help. They look pretty good to me, maybe lean? They all pretty much look the same. The heat band on the ground straps comes to within at least 1/16 to 3/32" of the body on all of them, some go all the way to the body. The pictures are a little screwy b/c of the led I was using for light put bands in the pic. Any insight is appreciated. These are Autolite 45's, I pulled them today to look at them and install some 44's I picked up.

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You can see in the last pic that the heat band on the ground strap goes all the way to the base on #3, #2 is very thin and #5 is just a bit higher than #2

I agree, Ap44's would be perfect. I tried AP45's & they were too hot & my ignition & A/F was spot on.
I use the Iridium plugs by NGK 7510. They are pricy but the heat range is perfect. Gap both at .045"

That's good to hear

I had the 45's gapped @ .045", I gapped the 44's at .040" b/c of a miss I have been having when the engine isn't fully warmed up. It's been running good, I had it timed to 14 btc but I picked up on some pinging on hard highway throttle, in the transition under load, a few times in the last week. I backed the timing to 12 btdc when I put in the plugs today at lunch. I only drove it a bit for the rest of the day, but enough to know it's running pretty good with the 44's. I found 2 sets of nos Autolite 44's so I hope they work out well. I tried to get it ping hammering it a couple times full throttle through the gears up incline. It did great, no pinging. I think the cold or sometimes idle miss is an issue with the ignition. Once it warms up, it purrs pretty nice most of the time. I've gone through the carb and it's about as goodas it's going to get with this carb. I think I'm going to swap to a TFI coil, and maybe an HEI module. Motorcraft and Delco and cross my fingers

This is a good thread, prompted me to do some research. Thanks

Hi, yes, it looks like you are going in the right direction. The gap at .040 and the timing should be fine. No pinging, ever. This is with regular fuel, I'm guessing. You seem to be in a good place. There is always room for improvement but unless you have OCD for power or MPG you can just enjoy it. Check the new plugs in a couple of weeks and enjoy the ride. Good luck

No I'm running high octane, I have to. 92/93 whatever they have at the pump. It looks like the timing is about right from the color change at the ground strap bend?

Hi, with modern fuel plug readings are not what they used to be. I like to see a uniform light tan or off white. I never heard of timing by plug color. I like to do what you did and get rid of the pinging. I always felt that gave me the best performance. Good luck