My Gen1 prius MPG update

Good morning everyone. Just wanted to drop in and update everyone with my latest MPG for my Gen1 Prius. Im pretty much max'd out at 52-53 MPG with the current temps. When it warms up into the 70s and mid 80's i should be able to possibly reach a tad more on the MPG. I am running 52-50 on the tire press. Tires are Michelin hydros and due replacement very soon. Tread is almost to the wear bars. Haven't gotten around to a front end alignment at this time, but will when tires are purchased and installed. Car is fast approaching 250K on odometer. Will probably get tires around 250-255K. In the past 2 years of owning the car i have put approx 30k on it and it has been very entertaining getting as much MPG as possible per tank. The mileage is very very close to the stated MPG on the dash. Usually within 1MPG. SO far so good. Has anyone seen any links to possibly using a laptop to access the ECU and hack into the system to change fuel maps to increase MPG? I used to own several Buick grand nationals, and we were able to access the ECU through software to edit and change the fuel maps according to Boost levels and RPM/SHift points. It was accomplished with tuning software and I know current GM cars/trucks can be accessed through "HP tuners" or "LS1 EDIT" brand software. Is there any type of software available to access the prius ECM to edit the fuel maps?

 

Thanks for the cudos. I have taken pretty good car of the car but the previous owner did change out the battery pack about 4 1/2 years ago. Thus far it has been very reliable. I do believe it will be front wheel bearing time in the near future.
I have read on here about quite a few mods, blocking off the grille, using a higher PSI in the tires, drafting etc to gain fuel mileage. Here is what I do on a daily basis:
#1 - I always purchase premium unleaded fuel - preferably NO ETHANOL, but that is becoming almost imposible to find today. The premium fuel does indeed give me at least a 2-3 MPG increase in mileage. I believe this car does have quite a few carbon deposits in the combustion chambers. All cars will accumulate some deposits. Its a by product of burning fossil fuels. The higher octane indeed makes my engine run MUCH, MUCH smoother than with standard 87 octane.
#2 I do keep the tires aired up to 42PSI. I attempted to push the limits to 50 PSI last year and developed a bubble on one tire that required replacement. When its time, i will purchase LRR with a 50 PSI rating if the price is right.
#3 I continually stick to 5 MPH under the rated speed limit. I don't want to be a jerk and crawl down the highway at 50MPH in a 70MPH zone, But IF NO ONE IS AROUND, i will slow down and enjoy 10-15MPH lower than Posted just to boost my economy while not infuriating the other drivers. LOL
#4 I do change my oil at every 5k miles. I use 0w-20 (Brand insignificant) but it is always a synthetic type. I just stick with whatever is cheapest.
#5 I don't carry anything extra in the car (stuff, work items, etc.)
#6 The BEST mileage i get is after the initial 10-12 min warmup period. First 10 minutes its very hard for me to best 50MPG. Impossible on first 5 minutes with engine cold. After that I feather foot it and back off on pedal and press lightly to maintain desired speed.
#7 I will sacrifice speed on hills to "rollercoaster" the car.
#8 I have determined routes that get my best MPG to and from work, Etc. My work route is actually about 8 miles further but I wind up getting about 6 MPG better on that route versus driving on interstate. Its 27 miles interstate and 35 miles on the MPG route. (Plus the route is nicer and good country views on way to work)
#9 I don't run my A/C unless i really need to. Once it hits 90 degrees here, i will run the A/C but I will only keep it set to probably 76-78 degrees in the car while driving. Of course, at first I blast it cold as it will go to get car cooled down a few minutes and then turn it to say 70 for a few miles and then up to 75-78 depending on my likes.
#10 - I do coast a LOT when i know i will be stopping soon. I let the regen pull the car down and slow me towards the stop. Of course, this is dependant on traffic and time.
I also own a 1995 Chevy Impala SS and a 2003 Silverado SS. You see what I leave in the garage most of the time! I even leave my Kawasaki 600R in the garage! Its crazy how frugal this car is!