I purchased my Prius C last weekend (coming from and Aveo 5 HB) and I did get the block heater installed. I was wondering about blocking the grill as well and was curious if I should just do the bottom portion? Or do both the top and bottom? Temps are falling fast......
I suspect Prius c strategy will closely resemble the regular model. In that case, block the lower-grille entirely once the you see temperatures like we are seeing now... highs around the mid-50's. I leave my upper-grille open all year long, even in the extremes we see come January. Others block it though. Let us know what you learn. Having an aftermarket gauge of some variety to observe operating temperatures is very informative.
Please be aware there are two radiators, engine coolant radiator and HV inverter coolant radiator. The normal temperature of the engine coolant is approx 190F (88C) and the inverter coolant temperature is cooler is better. Please refer to Gen3 Prius Grill Blocking strategy. The inverter coolant radiator on Prius c is located at the bottom same as Gen2 Prius. Therefore, my recommendation is leave the lowest part of grill open in the mild climate. Ken@Japan
Thanks for the info! What I suspected wasn't right then. Using the "block all the upper and most of the lower" strategy for Gen2 would indeed be better than what we do for Gen3.
Let us know how it turned out when your done. what method are you using, and could you post any pictures?
