[ps2fixer]

That pdf is pretty neat, kind of crazy you have to drop to enter stage 4.

Driving home from my parent's place is roughly 8 miles, the engine hit a peak temp of 172F if I remember right. I figured around 160F would be counted as warmed up, it took something like 3 miles for that temp. Upper grill is still open. I drove 30-35mph at first, then 45mph the rest of the way, short trip averaged to 50mpg. Guess I won't be seeing 50mpg from short trips at 55mph unless I have a full boat tail.

I figured the "B" mode wasn't good for mpg, it seemed like I could feel the engine turning over so figured it was engine braking too which is wasting energy, same as brakes effectively.

I got my scan gauge in today, added in the GAS and SOC xgauges, 2 pips on the gas gauge and I drove a ways on it and it was 25% yet. No clue how full it was for the first fill up but if I keep track of that, I suspect I can keep track of the bladder effect, maybe use the gas % to get the fill ups more consistent. I'm not sure how accurate it is though.

SOC is pretty interesting, looks like my car hangs around 59% quite often. Driving home on my dirt road at 20mph it takes roughly 2% not counting the take off (I thought of it as I made the turn so had to flip through the gauges to see it). It is a bit down hill then up hill for my drive way, ended at 57.5% if I remember right.

The MPG on the scangauge vs the in car display is very close to being the same. Clearly the scan gauge isn't calibrated yet to the car.

Looks like the rpm I was targeting was around 2100-2200rpm just a little high to be most effective, it's so quite so I guess it's kind of hard to judge rpm by year lol.

I'm thinking sealing up the front end as much as possible, and having some sort of slider door to allow for extra cooling in the lower grill block would be the best route to go. Seal front, under belly, and hood so any heat in the engine bay can be used to help heat the engine up quicker. On long trips might need to open the slider if temps rise too much. I think I'll probably need to buy one of those chinese digital thermistors to keep an eye on the inverter temp.

It would probably be pretty neat to get some digital gauges that I could control with a micro controller and setup analog gauges for engine temp, hybrid SOC, engine rpm (or load). The A pillar is a common place to throw gauges like that, shouldn't be too hard to tap into the signal wires without effecting the reading to the computer. With it already in the car, it could intercept the signals and adjust the signals for what the computer actually sees too and what the scan gauge would say. Like could make the engine temp "sticky" to the higher mpg modes so it runs less. As long as the computer runs in closed loop, I think it would be safe to spoof the temp warmer on the engine temp say +20F or more near the line where the modes change or make a lookup table. As long as it doesn't have a dead spot in the temp range it should be able to self tune the differences out and run like normal once it learns it.

I'd also like a "cruise" control that is stead pedal instead of steady speed, I suspect that would give the best mpg in the prius in most cases, let the mph change instead of the engine load/rpm and battery charge level. Idea is less using the battery at 41mph+ the more efficient it will be.

Either case, I think the Prius is good enough to keep. I think my 2004 Matrix will be going up for sale soon, I got a pretty good deal on it, so I probably can turn a profit reselling it. It had a trans line leak, pretty simple fix.

I haven't looked into the brake system too much on the wire diagrams, but I suspect it works somewhat similarly to the accelerator position signal. I'm not sure how much physical brake I'm using vs regen, clearly the brakes need to be used every once in a while to keep rust off them and such, but less use of the physical brakes and more regen would be more efficient. Just a simple button to hit to spoof the brake signal might be useful. The brakes are super good on the car, so I'm guessing the regen is working really well. My truck and my Lexus brakes feel like complete garbage compared to the prius lol.

Anyway, lots of ideas, just have to take action on what I can get done. Adding the micro controller in the car would be interesting to play with.

For my trips, roughly this is my travel pattern

3 days a week shipping out packages (10 mile round trip) all 55mph roads
1-2 days a week - I go up town, around 30-40 miles round trip. All 55mph roads till town then most are 45mph, couple spots are 30-35mph. I know the lights fairly well so I generally know if I'll make the light or not for coasting and such.

The road I live on is dirt (hard packed but bumpy generally, not much gravel in the mix). I'm roughly 1/4 mile from the corner, and it's up hill slightly from my house, maybe like 15-20ft higher than where my driveway is. My driveway goes up probably 5-10ft higher than the road with a dip in the middle. For the most part, my area is flat, minor small rolling hills, but generally no more than a 30ft change in elevation across a mile.

Anyway, I think my main focus will be the front of the car and main target would be areo and quicker warmup times, seems like the most logical starting point on this car.