I figure people do two as a safety for cold cranking - I am with you in SF and probably moving to san diego next year- not that concernd with cold-
I mean, it gets a little chilly here sometimes-- but i used to live upstate new york- its a whole different level of cold - WHOLE different level.
i have to do everything on the cheap in general, so maybe ill get one, throw it in the front and see if it works well, and if so, move it to under the seat. if its having troubles, buy another and do the dual in teh back.
thanks!
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