Insulating engine for higher mpgs

This is real easy to do, holds the heat in a bit. Obviously a bit different on yours, but:



(the short section of pipe insulation, centre of picture. The longitudinal groove is from the hood making contact)

 

I still have some 88C thermostats for the 1.5L engine. Send me a PM and we can do a deal.

Bob Wilson

 

Just my thoughts:

• MG2 is mostly cooled by radiant and convective cooling on the right side. As a general rule, the hotter the insulation, the weaker it becomes and we know this car already has a reputation for burnt, MG2 stator coils. IF you monitor MG2 and MG1 temperatures and keep them under 100C, it will probably be OK. Just remember "heat is the enemy."
• No opinions about keeping the engine warmer since in cold weather, it does lose enough heat to run the engine more frequently.
• I would be more interested in a bottom and sealing the engine compartment to air-block for the engine compartment. The bottom block to minimize drag at high speed. However, it would take pains to make sure the MG2 and inverter side still had abundant cool air.

Bob Wilson

 

Bob, you raise a good point: Toyota likely designs the whole system so it's within normal operating temps when stock. For example, first and second gen don't have a panel under the engine compartment, 3'rd gen does. If on a second gen. you do multiple changes, say add an underpanel, and lots of insulation above, you might push the limits too much, have something overheating.

Just thinking aloud; I guess the key is to not do too many things, especially in the absence of precise temperature monitoring, and the info regarding temperature parameters: assume there a bit of leeway for raising temperature, but don't push it too extremes.

 

I use Google for my DIY dentistry and in-home surgery too! Who needs a professional for anything these days?

Blankets are for babies. I filled my engine compartment with spray-foam. Smells like burning every time I drive, but no one can beat my mileage!

 

What happened maestro? You were doing so well when playing with others. I was even thinking I should give you some credit for that. Are you having a bad day?

 

Now there is one thing I didn't mention, spoofing the ICE thermostat so the engine 'thinks' it is warm, 70C. The reasons this works is if the coolant falls below 64C, the ICE comes on just to heat the engine. It happened this morning when I was coming into work and forgot to turn off the heater at a long stoplight. This chilled the engine enough I was a little surprised it came on. The light was a the end of its cycle so I just waited for the green . . . no big deal. But one trick to prevent these fuel wasting events is to spoof the thermostat:
NHW11 Prius Temperature Hack

Bob Wilson

 

haha, i like that, im gonna stop at home depot tomorrow after work and try this. i cant wait. ill post pictures after im done. oh how many cans of spray foam did you use. lol