Cold = Bad, What to do?

[Ryland]

If the slower route is 30% longer then your mileage needs to be 30% better on that slower route just to break even unless you are ONLY looking at the MPG figure, but I would look at the Gallons per week figure, the same figure that says that a 4 mile trip is reasonable in nice weather on a bicycle.

[redyaris]

Three or Four miles is a bicycle trip, 4 out of 5 days a week...

[undata]

Originally Posted by Sovereign

Thank you, but, between the two existing options, which is better?

Back roads definitely. Only a dummy would willingly drop onto a super-highway with a dead cold engine. Fact. Need for (just a little) proper warm-up has not disappeared just because car manuals have been re-written.

[bestclimb]

A couple of blocks is plenty of warm up especially with a block or oil pan heater. that said back roads offer more opportunity to improve mileage without annoying other road users.

[wobombat]

I've heard horror stories of block heaters creating insanely high electrical bills. One of the things an engine does best (or worst rather) is create a bunch of heat, so I would say keep the car in a garage that hopefully is reasonably warm, then drive it normally. As long as the engine block is kept at a normal temperature until startup, the losses of driving it on a cold day versus a warm day should be minimal.

Remember that the engine has to warm up to somewhere around 180-210 degrees F, so regardless of the weather the engine still has to warm itself up at least 150 degrees to get to its normal operating temp, so I imagine that the bill for operating a block heater would be much larger than the loss of running an engine rich for an extra minute or so. And if the highway route is indeed shorter and you're driving earlier than most of the traffic then definitely take it.

Now I don't have data to back this up, so if anyone does, feel free to prove me wrong.

[bestclimb]

My commute was 18 miles or so. Mornings I used a block heater 65+ mpg on the drive to work was easily attainable. Mornings I did not use the block heater 55 was a struggle. The mile out of my neighborhood would see at least a 10mpg drop if I did not use the heater. I did this several times. I realize the plural of anecdote is not data but it certainly convinced me. If you run the block heater on a timer the hit to the electric bill is not much (if you run it all night...well stupid hurts)

Additionally I would have hot air coming from the vents before the mile in the neighborhood was up (20mpg speed limit) With out the block heater I would have warm air about a mile or so after I hit the 55mph road. So on the comfort (and safety as I could keep the window defrosted) the block heater is totally worth it. The fuel savings is a nice bonus)

[MetroMPG]

Originally Posted by wobombat

I've heard horror stories of block heaters creating insanely high electrical bills.

What? Sure, maybe from doofuses who leave them plugged in all the time.

A "powerful" block heater may be 1000 Watts (1 kw). 1 hour is sufficient to pre-warm an engine (outside of Alaska). How much do you pay for 1 kWh of electricity? 10 cents?

I imagine that the bill for operating a block heater would be much larger than the loss of running an engine rich for an extra minute or so.

Depends on the vehicle and trip length (the shorter the trip, the more potential savings).

low cost
The study found that for vehicles with a block heater connected for just three hours prior to being started, electricity costs over a 112-day winter were between $10 and $25, depending on the vehicle model. During that same period, the net fuel savings ranged from $20 to more than $40.

source: CAA-Québec - Block heater: get connected!

[darrylrobida]

why worry about the day to day?
My cold/heat problem is to design a surface mount heat exchanger to totally replace
the radiator. thus more aerodynamic options. Pls refer me to t thermodynamics guy if
u know one. Thanks