Well the ol 4x4 rule fits this one. Four of us will Say go left and the other four say go right. I battled both the Tilly and the Zenith until I got them both to run well. I like the Zenith because they were designed for the "A". After a solid rebuild and flow testing the jets I get 19.5 mpg. After hearing about heating the tilly castings in Mama's oven to straighten the warped flanges (it works) I have two nice Tilly's I keep in the trunk. Only my opinion but the Tilly seems to be a little quicker off the line. Have not heard of the Hatch book.
