My k5 mpg blew my mind today? (305 ci)

[Rule_So_Hard]

83 k5 117k 4 barrel quadrajet.
Okay so I finally fixed all the vacuum lines and ran some carb cleaner through the carb and its waaaay better than it was. Today we had about 100 miles of driving for Xmas so I knew we needed the extra room for presents so we took the K5.
I rolled into the gas station at 99.5 miles and rounded up to 100. I go to fill her up hoping to have less than 10 gallons and the pump shuts off at 9 bucks. Gas is 2.29 a gallon here so that's like less than 4 gallons? I figuredninwas pumping too fast so I give thebteigger some light pressure and it shuts off again at 9.16.
I mean I've been cursing this 305 all day because it is the most gutless engine ever. My k5 wont even break 1 tire lose in gravel.... 100% serious. But 25mpg?????? Holy cow. We had the wind blowing into us otw there and I couldn't maintain speed at 70 without kicking down to 3rd. In went 65ish there and then otw back in took xcountry roads and did 55-60 the whole time.

 

[Green79Scottsdale]

 

[350runner]

That's freaking awesome!

Sent from the dust in front of you!

 

[Rule_So_Hard]

That's freaking awesome!

Sent from the dust in front of you!

That's why I'm confused... Math is math but it doesn't make sense, it even has 31" tires. But how it got better mileage than factory rating idk

 

[Green79Scottsdale]

I think there will be a lot of guys curious about your exact set-up. CCC Quadrajet in 83? Timing setting? Carb settings? Gear ratio? It's hard for me to believe 25 mpg, but I have an open mind...

 

[350runner]

700r4?

Sent from the dust in front of you!

 

[Rule_So_Hard]

I think there will be a lot of guys curious about your exact set-up. CCC Quadrajet in 83? Timing setting? Carb settings? Gear ratio? It's hard for me to believe 25 mpg, but I have an open mind...

Hey I'm with ya, I got 6 mpg on my past tank with the vacuum lines all messed up.
That's why I have absolutely no clue how. But 4 gallons at 100 miles is 25 mpg.

And yeah I have a 700r4. The RPO codes are gone from the dash so I plan to check the gear ratio when I do the brakes this weekend.
I have nothing done to it.but a custom muffler I made and a tall filter with a moroso air cleaner. And it's still not perfect because the the secondaries are locked out by the choke 50% of the time and the other 50% the secondaries come on too soon. It has a lot of little.issues that need worked out yet.

 

[Rule_So_Hard]

700r4?

Sent from the dust in front of you!

Yes 700r4 with a new filter and type f fluid, TV cable adjusted up a little to hold gears a little longer. The only problem with The trans is it locks the torque converter up as soon as it hits overdrive.....which is really inconvenient. I just hit the brake enough to keep it unlocked until in reach a higher speed. Like I said its a project and has a lot of little stuff needing worked out.

 

[350runner]

Yes 700r4 with a new filter and type f fluid, TV cable adjusted up a little to hold gears a little longer. The only problem with The trans is it locks the torque converter up as soon as it hits overdrive.....which is really inconvenient. I just hit the brake enough to keep it unlocked until in reach a higher speed. Like I said its a project and has a lot of little stuff needing worked out.

Good deal bud! I wired in a switch that cuts the power to the lock up solenoid. I flip it on when I'm cruising at 60 plus. works great for me 17.5 on highway rides.

Sent from the dust in front of you!

 

[Rule_So_Hard]

Good deal bud! I wired in a switch that cuts the power to the lock up solenoid. I flip it on when I'm cruising at 60 plus. works great for me 17.5 on highway rides.

Sent from the dust in front of you!

Yeah that's in my list of things to do. Its a Long long list

 

[350runner]

I wonder if this mpg spike is due to that custom muffler.

Sent from the dust in front of you!