Still getting poor mpg. Possible culprits?

[Daryl]

Last time I threaded up on this I was at 14mpg. Since then, down to like 12mpg.
I’m not driving any differently, etc etc.
I cleaned the TB, MAF sensor and air filter. Probably unrelated, but also installed new thermostat, thermostat housing, water pump and radiator flush/fill.
Using same Chevron 89 pump gas and Techron additive/fuel system cleaner every 3k.
So what can I do? Where am I missing the boat?

As always, I appreciate and welcome any/all input.

 

[Slice]

With the cold weather your fuel mileage always drops. Maybe don't stress over it and see what happens in the summer.

 

[white95]

How about the fuel pump strainer in the tank?

 

[Daryl]

How about the fuel pump strainer in the tank?

Pretty much brand new with the new tank, sending unit, etc I did a short time ago

 

[Daryl]

How about the fuel pump strainer in the tank?

In place, also new-ish

 

[Snorky]

Are you the type to let it warm up to temp before driving? You really only need to let it idle enough to get everything coated in oil before driving. Then just don't thrash on it like a lunatic till the engine and oil get acclimated to temp.

A lot of people idle their cars for extended periods of time to warm them up which murders gas mileage.

 

[badass98svt]

Did you replace the fuel filter, Daryl?

 

[Daryl]

I do it right along those lines: get in, start it up, wait a few seconds then head down my street slowly, max 2,000 rpm first couple of miles. And even beyond that, once driving around doing errands, etc, I rarely beat the snot out of it…and never for long stretches of driving

 

[Snorky]

I do it right along those lines: get in, start it up, wait a few seconds then head down my street slowly, max 2,000 rpm first couple of miles. And even beyond that, once driving around doing errands, etc, I rarely beat the snot out of it…and never for long stretches of driving

What gears are in the rear?

 

[Daryl]

What gears are in the rear?

3.55

 

[RAU03MACH]

the engine is stroked

 

[Daryl]

Yes. A 347

 

[Daryl]

Did you replace the fuel filter, Daryl?

Yes

 

[ttocs]

I thought it was, what kind of mileage are you expecting?

 

[Daryl]

With the cold weather your fuel mileage always drops. Maybe don't stress over it and see what happens in the summer.

A definite option but I want to do some more digging first.

 

[Daryl]

I thought it was, what kind of mileage are you expecting?

Not sure but I know I wasn’t expecting this low of a mpg

 

[porterhousestk]

Just some ideas: are your tires inflated well enough? no dragging brakes/parking brake?

 

[badass98svt]

Yes

It is flowing in the correct direction?

 

[RAU03MACH]

your fuel milage is crap due to stoking your engine

 

[Daryl]

Just some ideas: are your tires inflated well enough? no dragging brakes/parking brake?

All good there: 32psi x4; off the ground the fronts spin “a good turn” when I give them a (manual) spin around; and parking brake sets/releases perfectly.

PS- oh damn, your moniker has me wanting one medium rare!