Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - View Single Post

bwilson4web · 03-30-2011, 09:08 PM

Hi,

With that many miles, the tires are probably OK but you may want to shop early for low, rolling resistance tires. Now my understanding is the EU practice is to avoid tire rotation so front tires wear out first and are replaced in pairs while the rear tires wear out on a longer schedule. Credible USA sources for tire rolling resistance is poor and I know even less about EU sources on tire rolling resistance.

You may want to consider an engine block heater. When temperatures fall below the 3-5 C range, a block heater can materially improve mileage. Some folks advocate year round block heater usage to handle the universal, cold-start, fuel burn.

BTW, I'm under the impression the EU, NHW20s (your model) do not have a coolant thermos to accelerate ICE warm-up. However, Ken@Japan shared some warm-up data and it has an advanced warm-up profile. Still, the car responds best if lower power is used in the first mile or so during the ICE warm-up.

If the car does not have an EV button, there are many hacks to add one. However, EV mode has marginal use ... primarily to move the car around a parking lot ... and scare the horses. <grins>

Instrumentation helps and I find ICE rpm and coolant temperature to be the two most useful. Coolant temperature because until it reaches 70C, the ICE tend to burn more fuel to improve warm-up. ICE rpm needs to stay under 2,200-2,600 rpm to stay in the high efficiency regions. Higher rpms are not bad but rather ... less good.

GOOD LUCK!
Bob Wilson

03-30-2011, 09:08 PM	#8 (permalink)
bwilson4web Engineering first Join Date: Mar 2009 Location: Huntsville, AL Posts: 843 17 i3-REx - '14 BMW i3-REx Last 3: 45.67 mpg (US) Blue Bob's - '19 Tesla Std Rng Plus Thanks: 94 Thanked 248 Times in 157 Posts	Hi, With that many miles, the tires are probably OK but you may want to shop early for low, rolling resistance tires. Now my understanding is the EU practice is to avoid tire rotation so front tires wear out first and are replaced in pairs while the rear tires wear out on a longer schedule. Credible USA sources for tire rolling resistance is poor and I know even less about EU sources on tire rolling resistance. You may want to consider an engine block heater. When temperatures fall below the 3-5 C range, a block heater can materially improve mileage. Some folks advocate year round block heater usage to handle the universal, cold-start, fuel burn. BTW, I'm under the impression the EU, NHW20s (your model) do not have a coolant thermos to accelerate ICE warm-up. However, Ken@Japan shared some warm-up data and it has an advanced warm-up profile. Still, the car responds best if lower power is used in the first mile or so during the ICE warm-up. If the car does not have an EV button, there are many hacks to add one. However, EV mode has marginal use ... primarily to move the car around a parking lot ... and scare the horses. <grins> Instrumentation helps and I find ICE rpm and coolant temperature to be the two most useful. Coolant temperature because until it reaches 70C, the ICE tend to burn more fuel to improve warm-up. ICE rpm needs to stay under 2,200-2,600 rpm to stay in the high efficiency regions. Higher rpms are not bad but rather ... less good. GOOD LUCK! Bob Wilson __________________ 2019 Tesla Model 3 Std. Range Plus - 215 mi EV 2017 BMW i3-REx - 106 mi EV, 88 mi mid-grade Retired engineer, Huntsville, AL Last edited by bwilson4web; 03-31-2011 at 12:33 AM..