Rod,
You still rolling with the piece o' scheit stock tires on your nice shiny Kirkham?
Before you invest in a set of Webers or fuel injection you need to buy a set of Avons or Billboards so you can put a bit more of your FE power to the ground.
I have a set of Avons but don't know the original tread depth; my tread depth has decreased quite a bit on my rear tires since I got them.
Stentor