I have to replace a rod with a bad cap, so, when I pulled the head to my surprise I find the motor is still fitted with cast iron pistons. Then after cleaning off a light layer of carbon I see a small ford script stamped on the top-center of the piston with the word STANDARD in capital letters to the right of the script. All of this becomes even more interesting when see that the valves are modern stainless with hardened pressed-in seats and modern valve spring retainers. Naturally the motor has been worked on previously, but the fact that the bore is standard and still fitted with the old cast iron pistons is interesting, at least to me. No evidence that the block was sleeved either.
Some people in the T world hate cast iron pistons. Others, including me, actually like them. I would say, without a doubt, that in all total balance of all the various factors involved, that using aluminum pistons is better than using the cast iron pistons.
Cast iron pistons came in several varieties. And the weight of the piston and the placement of rings as well as the use and size of oil holes in the lower ring groove makes some cast iron pistons somewhat better than others. Of course, lighter is better, generally speaking. However, proper balance between all four pistons is more important yet.
And while I will use cast iron pistons (provided the bore is good, straight, and round), I do not use the original two-piece valves in a model T to be driven. The likelihood of them breaking apart while driving and then destroying the engine is just to great.
So you may have a good start to a decent driver. But you may need to check further for poor quality work or bad choices. The bad rod cap is a bit of a red flag. (I also hand cut and fit old bearings into my engines. Done several that way. It can be done well! Or not.)
Years ago, my wife purchased a '25 Coupe from Montana - after an AWOL trans. band nut found it's way between the field coil & magnets to make a "spaghetti" entrée, I rebuilt the engine - new mains & rods but was a standard bore with minimal wear so the cylinders were honed, new rings fitted to the original cast iron pistons - one of the best running T engines around !