I got the DIY written up on the grill block:
DIY coroplast grill block
Also, after using the grill block for a few days now I can definitely say that it helps warm up times. I monitor coolant temps and if I can I wait to turn on the heater until coolant temp is over 169°F due to the PTC heater kicking in. So, I'm quite familiar with the 150-170 range. It definitely has sped up the warm up times there.
" I wait to turn on the heater until coolant temp is over 169°F"
That's dedication. I probably turn the fan on low as soon as it climbs past 70!
Its kind of odd. I attribute it to whatever heater core issues are going on, but the Mirage's coolant temperature has to be substantially warmer than other cars I own to blow warm air. Typically on my 04 Civc, I waited for the coolant temp to get to about 130F and then it would blow warmish air. The same goes for my Prius. On the Mirage, I have to wait for darn near 160F to start getting warmish air. I don't get hot air until the coolant temp is up around 180F. Today on my drive in it was 4F outside, and even with the coolant temperature up around 190F, the air coming out of the center two vents was only lukewarm with the fan on max.
This morning I forgot to plug in the block heater. It took a full 1 mile (of my 7 mile commute) to get up to the temperature I typically start at with the block heater. I tried very hard, and got lucky and got 'stuck' behind a bread truck doing 0-5 mph under the speed limit. Still, I only managed 45 mpg. Lately, I've been getting 47-48ish, and really not trying hard at all. So, I think its not unreasonable to say that the block heater probably nets me ~10% increase in fuel economy in the winter on my daily commute.
In contrast, today I remembered my block heater, and I tried to get good fuel economy coming in. The result was a hair under 51 mpg on the MFD.
I like the glove box light. I need to get on that.
2014 White SE with CVT
Thanks! Its been working very nicely. A kit will be for sale pretty soon.
I just took my Mirage on the freeway for the first time since the grill block modification. The coolant temps were rock stable at 195F. Ambient temperature was around 30F I believe. No concerns about overheating, at least until it gets warmer.
Also, I was able to get a respectable 47 mpg on the trip there and back. Not too shabby for winter.
2nd fill up in the Mirage this weekend. I am a bit disappointed at only 38.1 mpg, but it has been pretty brutally cold.