There are "dipstick" heaters that warm the oil and can be left in place while driving, but the percolator heaters that are plumbed into the heater hoses will probably do a better job of keeping the entire engine warm, plus you'll have heater operation almost immediately.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!