92 VX Seeking 50+ MPG

[Lovemy92vx]

I just hit 270,000 miles.
The second tank of Conoco 85 looks promising. My trip meter is at 275. The gauge is just below half way. I estimate two more "gauge drops".
Thus this looks like improved MPGs.

Next fill should I switch to higher octane?
Yes, I will put in a bottle of Techron.

Considering the overflows probable over it's lifetime, should I replace the charcoal filter?

Another 80 mile road trip and I Have to see the MPGs!
Should I test the 91 octane when I refuel?

[user removed]

Forget the higher octane unless you are going down to sea level altitude.

I would only replace the charcoal filter if you can confirm it is bad. The charcoal holds fuel vapors in suspension. Those vapors are released into the intake manifold the next time you start the car.

Symptoms of a failed charcoal canister would be a fairly strong fuel smell after shutting the engine down or after refilling the tank. To prevent the normal fumes from a refill being incorrectly diagnosed wait at least ten minutes after a refill.

Charcoal canister replacements are so rare, the only ones I replaced in 30 years were due to collision damage.

regards
mech

[user removed]

Best VX tank for me was exactly 300 miles on 4.625 gallons of gas, 68 mpg, same day same pump same station, with about 500 pounds total payload. Sounds like you are close. No reason to not refill after 300 miles if you want to know for sure.

regards
mech

[Lovemy92vx]

Met my 50+ goal yesterday: 52 MPGs!
I had to change back to my local Shell station, added a bottle if Techron, filled it with 87 and did the math. Parts or driving conditions? Who cares? I am happy. Will be happier after two more tanks.
Conditions:
Weather: cool (50's-60's), some rain, windy generally
Road trips: 4 trips average 45 miles @60mph
Commute: 5 days, 7 miles to and from. 3 days 60 mph, add 2 days city w some bad stop and go. I idled. I am studying how it is working since all the new parts
Driving style: shifting by lights and 2000 rpm, but tested accelaration a couple of times. (Good power)
Tire pressure: 44/40
Also, I drive like I'd ride my bike, coasting whenever possible. Is it better to coast clutch in or out? I am still anxious about EOC...
I also explored 5th gear on level or steady grades (found that comment about being able to accelerate evenly from 30 mph.
Fuel: 2 full tanks of Conoco 85

Pretty neat.
I am excited for warmer weather and more road trips. I am on vacation next week.
Can't wait to clean that EGR still