Today I removed the 4 plugs, 3 are the same "Autolite 3095" and 1 is a "Champion X".
I will fit 4 the same in time but I live remote and cant get plugs locally so in the meantime while I'm waiting I still want to drive the car every day but first,
Two questions -
1. the length of the X is quite a bit longer that the others...is this an issue?
2. The electrode on the X is bent to the side not over the top?
Also I gave an compression test and all 4 read 90. What does a healthy standard engine read?
Here is some pics to clarify
Yes, the electrode on the X is supposed to be that way. And no, the extra length isn't a problem.
I just noticed the bit about compression. Is that 90 Celsius? I think 55 or 60 psi is generally considered mighty good for a Model T.
Thats interesting as it is 90 psi on my tester? (which is just under 8 kpa x 100). I dont think it has a high compression head, not that sure as I havent owned it long.
Thats good news about the plug, I will refit them and go for our usual evening cruise.
"I just noticed the bit about compression. Is that 90 Celsius?"
Haha, good one.
Kevin, put the X plug in #1 cylinder, it will probably burn cleaner than one of the Autolites.
If it doesn't have a high compression head, maybe it's got domed pistons.
Its a bit confusing as I read up a bit last night and it is much higher than normal. My tester is in new condition but could be reading wrong. At least they were all the same.
Jerry, they could be domed I guess. I'm trying to contact the guy that restored the car to get more info.
Ken, yes I did put the X into number 1 as thats where it came out of but your thought makes sense. All 4 plugs were relatively clean when removed so I just gave them a light brush.. I guess the mixture is set about right.
I usually never adjust it from 1 full turn out. I've tried the odd time when climbing or cruising and it makes no difference.
The car is not easy to turn when cranking but I havent cranked any others lately to compare, when cold it is very stiff to turn for the first couple of spins I guess thats thick oil.
I tracked down a previous owner in NY who restored the car in early 90's and was surprised to hear he only done the body, never touched radiator, engine, trans, diff at all. He said the car was restored in 1960's, I have heard that some people used Mustang Pistons in that era so maybe this may account for the compression?
Probably Y Block Pistons. There are no Mustang Pistons that would work.
Would these be high compression?