Could someone tell me the diameter and length of the Model T valve pins?
They cost .25 each - why not just buy some?
I have some A2 drill rod, so I thought I'd save the postage.
I have 7/64" (.109375) and 3/32" (.09375) rod. Would one of those sizes work?
Make sure those pins are HARDENED. It's surprising how quick they can wear thru and you'll be limping in on two cylinders.
Use a 7/64" drill bit and cut the shank off.
I found the repro ones sold a few years back to be awful - they would break after about 500km of driving. Thus, I know the 2 cylinder routine well!
You could easily notch them with side cutters, so were obviously not hardened.
Ditto on the poor quality repo ones. Use drill rod and harden it.
Ford spec is 7/64" X 17/32"
There was a problem with valve pins several years ago. The ones being made were soft and didn't last. The valve pins currently being sold by Lang's are hardened. I don't know what any of the other suppliers are selling.
I have usually just cut the closest fitting nails I had handy to length to fit the spring cup. Usually, that seems to work just fine.
One time, it didn't work so well. I have no idea why, but one of the nails I used was too hard. After only a few hundred miles, not one, but three of the pins BROKE under the strain of those really strong stock model T springs. Fractures were in the center of the valve stem and pin parts worked out. I actually completed a tour and drove home by carefully placing two halves into the valve stems.
Because I wasn't sure what nails were which or how many pins? I more carefully chose a couple different nails, and replaced all of the pins. That all happened about forty years ago, and I haven't had that problem since.
Drive carefully, and enjoy, W2