I've been distracted lately by a Prius purchase, but I'm looking at buying caps soon. My main concern at the moment is engineering the best balance circuit possible. I'll be buying 5x of the BCAP3400 caps to maximize the farad rating and keep costs down.
I created
this very rough spreadsheet that auto-calculates things like how many days a vehicle can sit and still be able to start. It must be opened to input your own values. Look for the Cap Calculator tab and enter values in the top right box to see the calculated values.