[Isaac Zackary]

Originally Posted by vskid3

What kind of mileage are you seeing so far? They do pretty good for how big they are.

Thanks!

I get 41mpg. That's nearly all highway. That's what I got when I drove it back home (1,500 miles) going 75mph with the A/C on the whole time. Today I took it on my usual 150 mile route over the mountains. Again I got exactly 41mpg, even with the steep grades. (At least according to the average MPG meter on the dashboard.)

Originally Posted by vskid3

Toyota ditched the heat tank with the Gen3 Prius and switched to having the exhaust heat up the coolant for faster warm up. Heat tank seems like a complicated solution that only helps in specific use cases. Your Avalon might have a system in place to decrease warm up time, but I haven't looked into them enough to know. If it doesn't, I would lean more towards something like the Gen3 Prius' system than the Gen2.

From what I can tell the engine warms up very quickly, so it must have some sort of exhaust heating system. Still, I'd like to warm it up before driving, especially in the winter. We get clear down to -40°F/-40°C on occasion.

A regular block heater would do. I just need to get ahold of a dealer to find out what part I need since I can't seem to find one anywhere on the internet. Then I'd also have to figure out where it goes.

However, something that can heat the engine without being near a plug would be great. And a heat tank doesn't use energy (except the pump). It would add more weight though. I've also thought of a Webasto or Eberspacher fuel burning heater. But those would likely need a small diesel tank to work. There are a lot of situations where I'll have to leave the car for hours where I can't plug it in during freezing weather, hence why something portable would be nice.

I'm not so concerned about heating the engine for comfort or solely for fuel efficiency. I want to make the engine last as long as possible. And cold starts are what do the most damage.

Originally Posted by vskid3

Unless you have money to burn, I wouldn't mess with adding battery capacity. I think CNG would make more sense and pay off quicker than messing with the battery.

CNG retrofitting doesn't seem cheap either. And yes, the Enginer kits seem quite steep in price. Basically, if I want to save money I'd have to source my own parts instead of using prefabricated kits. And old Chevy Volt batteries seem to be a better bargain than DOT certified CNG tanks. Plus electricity is easier to "trick" into accepting another electric source. Electricity is electricity. But getting the engine to accept another type of fuel is not as easy.

Originally Posted by redpoint5

Are there examples of Avalons that have been converted to plug-ins? In other words, is the Avalon designed to run in an EV only mode as it is? If not, I don't see the point in adding battery capacity. If the EV mode is like the Prius, then you'll be limited to very low power and a top speed of something like 40 MPH.

My Avalon with has an EV mode that quits at 25mph, although I can get it to drive with the engine off at speeds below 47mph.

But that's not entirely the point. If setup right the car could run in a gasoline/electric blended mode for long stretches. So instead of 41mpg I might be able to see 60mpg or better. Of course I'd have to figure in the cost of electricity. But with electricity costing 10 cents per kWh around here (and lots of free charging station including at my place of work) I wouldn't worry about it that much.

Also I do a lot of highway mountain driving. Even if I didn't make it a plugin-hybrid, just having enough battery capacity to absorb my descents would be great.