Hi Mike, I might be one of the guys you are looking for. I'm in the process of fitting up a throttle-body fuel injector (TBI) to a model A. Aside from just fooling around, my primary motives are to find out how efficiently a 200 ci four-banger can be made to run, and whether it can conform to modern emmission requirements. BUT, one could also do this with speed and power in mind. I am using a throttle body from a 1990 Pontiac "Iron Duke" (2.5L) engine with throttle bore of 1.720 inches (the original Zenith is 1.181).
Let me warn you that its a lot of work. First of all, the manifold has to be either substantially modified or completely fabricated to accept the TBI. Second, the engine must be converted to 12 v negative ground. Pertronix electronic ignition is required, and the exhaust header must be fitted with a boss (flange) that will accept an oxygen sensor. Your engine will have to be wired to the EMC (electronic motor control) which will completely control ignition timing. You will also need a thermostat and an engine temperature sensor.
Then the fun begins, because the EMC will have to be programmed to run your engine! For me, this is a game because I have fabricated the intake manifold to accept the TBI, the old Zenith carb, or a new Zenith FS carb intercangably within minutes. Once I have the engine tuned to the TBI, I plan to go back and see if I can tune it to the carbs using the O2 measurements from the oxygen sensor. This stuff just keeps an old man busy and out of trouble, if you get my drift. My wife is happy because she knows where I am and what I'm doing...
One additional note: if you are planning to do this for speed and power, you will probably need a Stipes 380 cam. The A engine has breathing problems and will not be able to utilize the TBI if it is not breathing correctly.
No, I have not finished the installation yet, and probably will not until this fall or winter. Right now I am enjoying my roadster for the summer tooting around Lake George as I am wont to do when I'm up there.
Affordable Fuel Injection made up the kit for me and I think it cost me about $1400. You might want to wait until I can report on it before committing that kind of money on a darn fool project like this though! Happy Motoring---