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I have made three YouTube Videos for driving a CMAX Hybrid/FFH the way it was designed to be driven, Called "How to drive a CMAX Hybrid/ FFH to get great gas mileage", also "CMAX Mods to improve MPG's" and "Hypermiling to improve MPG's". Efficiency and Aerodynamic Mods: The First thing to do is to raise your tire pressure of your Michelin's to 50psi which is safe to do according to Michelin with max pressure of 51 psi and I got 89k miles on my last set of tires on my CMAX. :) It is amassing how much you can improve tire tread life by raising you tire pressure to 50 psi. There are a lot of members on the four forums that use 50 psi. Hypermiling Video not recommended for those who can't focus on situational awareness of traffic around you all the time. Let me know what you think, any improvements. Paul

I have been doing a lot of general research to prepare for this winter with a comprehensive winter weather strategy to see the least decrease in fuel economy. Part 1: Grille blocking Last year acdii made a grille cover, see this thread, which he then kindly sent me as a gift after he got rid of his first FFH, the Blue Devil. I ran out of zip ties so I bought more on Amazon planning to put this cover on soon as temps are now consistently below 50oF. Since the temps dropped last week I've seen a marked drop in fuel efficiency. Trips that used to consistently get 60-65 MPG now are only seeing 50-55. My current tank average has dropped from about 57.5 MPG over the first 200 miles to now 56 MPG over 275 miles. These last 75 miles have taken a big toll on my fuel economy averaging only around 52 MPG. Unfortunately, the zip ties I bought are being shipped from China. I'm am quite annoyed at Amazon that nothing prior to purchase indicated that they would be shipped from China and that they would take 3 weeks to arrive. I expected them to come like most Amazon items in about 1 week or less. So while I'm stuck waiting I decided to do more research. Grille blocking is useful to help the ICE warm up faster and to insulate it to keep it warm longer. The cold winter air flowing over the radiator and engine compartment while you drive quickly sucks the thermal energy out of the components that you want to stay warm for maximum efficiency. Since the FFH is designed to spend a large percentage of its miles with the ICE off this is a problem in winter. However, you do not want to block the flow of cold air to the electric components. While the ICE is less efficient in the cold, the hybrid computer and electric components are not adversely affected by the cold. In fact, you want to keep those components as cool as possible to keep them from wearing out. Thus it is important to understand where the radiator is for the hybrid system and not block its airflow. In the FFH you'll see that there are two radiators. A large one with a fan, for the ICE, and a small one that is in front (closer to the grille) than the large one. The small one is for the hybrid components. In the FFH it is located down low and receives its airflow from the lower grille opening. The ICE radiator spans the entire height and gets airflow from both the large upper grille and the lower grille. In my past experiences with using acdii's grille cover on the upper grille (see this thread) I found that even in the summer the ICE didn't get too hot with the upper grille blocked. However, I didn't leave it on because I was concerned that the electronics would get too hot from the limited airflow through the engine compartment even though the inverter radiator being still exposed to air. Sadly, there is no way currently to monitor the temp of the inverter coolant. Hopefully someone brilliant will figure out the XGauge coding for that soon. Thus, my plan for this winter is to use acdii's grille cover on the top grille while temperatures are consistently below 50oF. Once the temperatures drop down below freezing I may block one row of the lower grille. I do not want to block any more of that lower grille to keep the electric components as cool as possible. I discovered that as soon as the car is turned on the coolant is flowing through the inverter radiator. Even though the ICE was not very warm and the inverter coolant was barely warmer than room temperature the coolant was constantly flowing while the car was in park sitting in the garage in my tests this evening. I want to further test this when the car has been sitting for hours and the ICE/inverter components are completely cold but it seems likely that this coolant will circulate non-stop when the car is on regardless of temperature. For this reason I don't want to interfere with that by blocking the lower grille except partially in extreme cold. The reason to consider partially blocking the lower grille in extreme cold is because the ICE is still cooled by that grille and in extreme cold blocking the upper grille only might not be enough to keep the ICE warm. The common Prius grille blocking links talk about only blocking the lower grille on the current gen Prius since its inverter radiator is located up high. The Prius also appears to constantly circulate the inverter coolant anytime the car is turned on regardless of temperature. Part 2: Use the heated seats Instead of turning on the HVAC right away when the ICE is cold I plan to use the heated seats for initial warmth. Turning on the heated seats will not make the ICE come on like turning on the HVAC will. On low each heated seat draws about .13 amps from the HVB or 0.0364 kW. This is a minimal power draw, less than the headlamps. Part 3: Intelligent HVAC use I use "intelligent" here to mean that I'm applying my knowledge of the FFH's inner workings to how I control the HVAC settings. Since below a certain coolant temp threshold the ICE will run constantly to make heat I don't want to turn the HVAC on until the coolant temp is warm enough not to interfere with normal operation. Since the PCM update modified these settings I don't know yet what that temperature is. I also plan to not set the HVAC temp any higher than absolutely necessary. Parts 2 & 3 will improve efficiency by not causing the ICE to run only to make heat which is not efficient. Part 1 improves efficiency by getting the ICE warm faster and keeping it warm longer. I don't sacrifice much personal comfort to do this since in the winter I'm already dressed for being outside and don't need much heat anyway. When leaving from home our car is also parked in a heated garage so we always get into a warm car at the start. In any car you wouldn't have heat immediately so turning on the HVAC on from the start does no good. With the grille blocking strategy I hope to dramatically lessen the ICE warm up time so that the delay compared to a gas only car is minimal. I wanted to share this strategy so that others can consider implementing any of the above steps or adding their own suggestions. Once I know the minimum coolant temp to turn the ICE off and still have heat I will add it.

From the New York Times http://www.nytimes.com/reuters/2013/07/16/us/16reuters-autos-ford-hybrids.html?hp I imagine this will be discussed more in the days to come.

I recently bought and installed a ScanGauge II in our FFH. After driving a 100+ miles with in installed over the past few days I have a number of observations and a number of questions... Observations Horsepower - the generator can place about a 15 horsepower load on the ICE when the battery is low and the ICE is doing maximum recharging. This is good for about 18 amps of current flowing into the HVB. In other situations it seems that each hp of ICE output to spin the generator is good for slightly more than 1 amp of current flowing into the HVB.Amps - the maximum regen braking charge seems to be about 30-35 amps. I've never seen the regen braking charge go above 35 amps while still getting 100% brake score. That seems to be the limit for the generator. When driving in EV 1 bar on the Empower screen is about 20 amps of current flowing out of the battery. The max current I have seen flowing out of the battery has been about 50 amps. This happened when I was accelerating in EV at 1.5 or 1.75 bars and then it kicked over to the ICE. Since one motor/generator must spin the ICE up to speed (like a starter motor in a conventional car) there is a momentary spike in amps flowing out of the battery to start the ICE.Recharging - The computer likes to charge the battery with a 15 amp current flow when the battery SOC is low to maybe about 75% of the display. This seems to be in the most efficient range of the ICE as well as the LOD will often be 85+ when this load is placed on the ICE by the generator while accelerating. When the battery SOC is higher than 75% of the battery icon the amps from the ICE generator drops to 5-8 amps. If the battery is almost full the current flow drops to about 3 amps.Coasting - when coasting with your foot off the gas pedal the generator places about a 3-5 amp load to gradually slow the car down.Idling - when idling the current draw to run the computers and charge the 12V battery is about 0.55-0.60 amps. This amount of current is drawn whether the car is in Park, Reverse, Neutral or Drive as long as you are not moving. The brake lights pull a minimal amount of current, but enough to make this range 0.59-0.64 amps when you are stepping on the brake.Lights - the headlights/taillights draw about 0.25 amps. The park lights and fog lights draw the same amperage as the headlights. If you combine headlights and fog lights the current draw is about 0.40 amps.HVB temps - the HVB temp quickly increases when driving from the current flow in and out of the battery. The past few days each morning the HVB temp showed the same as the exterior temp when first starting off (between 75 & 80 F) but quickly warmed up about 10 degrees within the first few miles of driving. Only on Friday where we did a lot of driving in the city in 95 F outside temps did the HVB temp go above 100 F. The HVB fans ran non-stop on Friday. Other days I noticed that at about 85 F HVB temp the fans would kick on at a low RPM (about 750-1000 showing on the display). On Friday I saw the HVB Fan RPMs as high as 2000. Even when running at that speed I still couldn't hear the fan when I got out of the car to listen with it "running" and with the SGII indicating a fan speed of 2000. I imagine that when we hear the fan running from outside the car after the car is off it must be running much faster than 2000 RPM.Current draw when off - after turning off the car in the few seconds before the SGII turns off the power draw shows 0.04 amps. This is likely to run whatever computers are still active to display the Trip Summary and Lifetime Summary screens.AC amp draw - the AC will draw 15-20 amps from the HVB when first turned on with a hot car. Once the car has cooled down the AC continues to draw an extra 2-3 amps minimum that we observed. This puts some numbers to the effect of AC on gas mileage. That is a lot of current that must be replaced by burning gasoline.Battery display on dash without charge/discharge arrows - It is very hard to get the battery display to show no arrows for charging or discharging. It appears that while moving the car displays no arrows when the current flow is less than 1 amp in or out of the HVB. However, sometimes the current flow will be less than 1 amp and the dash will still display arrows for charging or discharging. Also, when stopped a current flow of less than 1 amp displays as the HVB is discharging. No matter how hard I've tried I have never been able to get the display to show 0.00 amps as the current flow. With steady pedal pressure it is possible to keep the amp flow steady for many seconds though while driving as long as the slope of the road doesn't change.Warm up stages - when the ICE is in S1a the power demand on the ICE is very low, less than 10 hp and a LOD less than 60, this is quite inefficient and shows why skipping stage S1a improves fuel economy so much as discussed hereQuestions :headscratch: What exactly is LOD (Load)? The car often shows 95-99 when accelerating slightly more aggressively such as accelerating onto the freeway, when accelerating in the city it often shows only 80-85. When the ICE is idling in warm up the LOD is as low as 50. Is this the % of maximum power output of the ICE at the current RPM?How do I understand the ignition timing screen (IGN)? When the ICE is off it shows -10. When the ICE is on I've seen values anywhere from 5-8 (when ICE is under load accelerating) to 30+ (mostly when the ICE is under a light load but still on such as freeway driving where the Empower screen shows the power demand being just above the EV threshold.Why does the car show 1.2 horsepower when the ICE is off? I tried using the adjustment in the setup but even decreasing the reading by 10% only lowered the display when the ICE is off to say 1.0 horsepower. What does the default value of 1.2 hp when the ICE is off mean for the numbers that the SGII displays for hp while I'm driving?As I think of more items I'll continue to add to this thread. As it stands now I hope that my observations will be of benefit to others and that those with more experience and knowledge than I will be able to shed some light on my questions. Thanks in advance for that help! :worship: