coolant temp?
 

I have a grille block installed and now my temps are avg 90's compared to avg 80's before. Is this affecting reliability when it sometimes hits 95c.

I think it really depends on the vehicle. For instance my Jeep runs at 97-98c and it seems happy at that temp.

If the temp starts to climb above 100c I would maybe take a look at modifying the grill block. Just make sure it doesn't get over 110c that is usually when the rad cap starts to vent and above 112 or so bad things start to happen pretty quickly.

230f is the trigger for all the red lights and warnings on the 02 Infiniti Q45
therm opens at 180f

I had a full grill block installed initially and found that every couple of minutes of freeway driving would result in the temps rising to 100 until my fan kicked on and brought it back down to 94. I completely opened up the lower half of my upper grill and now temps never get past 95.

Did you observe a mpg increase, and if if so, how much?

My first drive, seems to be better but more testing needed to be sure. 0c degrees today can't believe I'm worrying about high temps,,ha ha!!

I think 90s is fine, last time I had Torque running it showed 78C on the highway with 40% grill block! In the summer, in traffic it goes up to 100, but freeway it stays at 85-90ish. I would imagine a little hotter is no big deal.

This is exactly what I have in my turbodiesel: Without grille blocks it barely keeps 78°C, with both blocks it crawls up to 90°C more often. Fan turns on at 97°C and cools to 89°C, so haven't had problem with overheating. Also, at 90° I see slightly lower fuel consumption at idle, like 0.48-0.52 vs 0.52-0.54 liters per hour.

You will notice that as you drive more efficiently, the engine will not be as hot. This is because you are wasting less energy as heat and using more to move the vehicle. You should start thinking about insulating the engine bay, this will also keep the engine from cooling off too fast, so it will be warmer when you start again after shopping, for example.

the average internal combustion engine is ~33% efficient on a good day... the other 2/3 of the energy is lost out of the exhaust and into the cooling system... so anything you can do to minimize the amount of heat(therefore, energy) going "unused" will help. turbos can harness a LOT of exhaust energy, but at the side effect of pushing a bunch more air into the engine, which requires more fuel to keep the AFRs in check...

a variable flow/capacity/surface area cooling system would probably help cut down on the heat lost to the cooling system, enough to offset the cost over the life of a vehicle i would think.