Since I've owned my T it has always turned over rather slowly, and i always wondered if this was just the normal result of having a 6V system, or if there was another reason. The car has a fairly new starter and i cleaned all the connections i could, especially the ground/frame contacts, with no noticeable improvement. The one huge mistake i made was trusting that my cables looked pretty good visually, although i knew they were probably 30+ years old. I decided to swap them out today, and the difference is amazing, it now turns over twice as fast as it did before. When i pulled them out and got a closer look at them, i could kick myself for not figuring this out sooner.
On a happier note, thanks to whoever makes these new cables for our T's, they're very well made.
John,I went through the same scenario. As you say.... what a difference! Having the correct gauge of cable goes a long way too.
One of the best ways to find minor issues like this is to run the starter with the ignition off for a short while (fifteen seconds should be enough!), then carefully run your fingers over every inch of every cable and connection. High resistance poor connections will almost always produce a noticeable warm area. I say "carefully" because sometimes that "warm area" is a bit more than a little warm. I still have a small scar on one finger from locating a high resistance intermittent connection on the starter solenoid of a modern car about ten years ago.
Glad you got your T working a little bit better!
I noticed the same thing on my 1919 Roadster. The battery cables were either originals or older replacement cables that seemed to look OK.
I finally spent the money and got new battery and starter cables and there was a really noticeable difference.
I later replaced all of the wiring in the coil box, timer wiring and switch wiring.
There was more of a difference this time! Smoother running and starting.