Thanks guys.
Biginchmopar: I'm used to the software from AEM so- thats something.

Thanks everyone, as usual, I get a good range of information .
In this case, to my surprise, I didn't find a solution I was hoping for which was- cheap! grin
I really just wanted to add driveshaft speed to what we are already taking ( afr/engine vac/rpm ) and was shocked that everything I looked at was well north of a grand to get set up and running.

What i learned here confirmed my research- data logging "costs what it costs" no matter which route you take.

I could get into EFI with data logging already there for about what Logging alone costs- but , we have a ton of money tied up in carbs right now.
I do think we may go that way when we do the Charger build though.

So, i'm down to comparing apples to apples at least .

Thanks again for everyones time to help.