9/10 mpg really?

[Yellow Horse]

Haha, I get 20-22 highway mpg with 4.10s
Drag racing... I see MAYBE 6mpg, and that's mostly on the return lane!

My 03 Cobra got 23 mpg at cruising speeds with 4.10's with 500 at the tire.

 

[sky1]

My stock 11 GT 500 with performance package gets around 16mpg in the city,and 19 -20 on the interstate.

 

[Bad500Chris]

My 03 Cobra got 23 mpg at cruising speeds with 4.10's with 500 at the tire.

Yeah, I usually don't drive much more than 65 on the highway... the car attracts enough attention as it is.
Revs a tad higher than 2k

 

[UnleashedBeast]

So, when I said I get two mph better at 80 mph than you, you think my gear ratio is wrong? :lol:

Retune your car, before you upload the tune, make sure axle ratio and rev per mile are accurate.

285/40/18 & 285/35/19 both are ~770 revs per mile.

What gears are in your car?

Do you use gas that is up to 10% ethanol?

 

[F8L SN8K]

KB 03 cobra with 3.55s, 60# injectors and ~600rwhp 22.6mpg with cruise control set at 75mph average from Indiana to Alabama and back. Now my driving habits in town are horrible for fuel economy.

Must be the Mobil 1 ;-)

 

[CPRsm]

Must be the Mobil 1 ;-)

Mines been sitting for a few months without oil. It's getting great mileage. Haven't spent a dime on gas in a while :dw:

 

[F8L SN8K]

^^
The 03 is my DD so it's out everyday/night but only back and forth to work(34 mile round trip). Lol just clicked 45k miles however my wife's 07 Ford 500(also ran with inferior Mobil 1) we drive all the time and it is approaching 77k and climbing quickly.

 

[Yellow Horse]

Retune your car, before you upload the tune, make sure axle ratio and rev per mile are accurate.

285/40/18 & 285/35/19 both are ~770 revs per mile.

What gears are in your car?

Do you use gas that is up to 10% ethanol?

Dude, I told you according to my GPS my odometer is exactly what the GPS showed. I run the stock 3.55 gear on stock tires/wheels. I will have Van verify it but according to my GPS it is correct. I don't have a calculator handy but if it were programmed for a 3.31 gear it should have been off at least 5-6 mph.

Not sure what the gas has to do with it unless ethanol increases mileage I htink is highly unlikely.

Same as oil. 5W is about as thin as it gets.

I run 93 octane.

I do not use cruise control on hilly roads. I lift before I crest a hill and I coast most of the downhill side. I rarely pull any boost and try to pull vacuum as much as I can when I drive.

 

[UnleashedBeast]

Not sure what the gas has to do with it unless ethanol increases mileage I htink is highly unlikely.

Ethanol decreases mileage. I was asking to see if the pumps where you buy 93 octane say "up to 10% ethanol content" on the pump. You could expect a 1-2 mpg decrease using ethanol blended fuel from 5-10%.

Same as oil. 5W is about as thin as it gets.

SAE grade numbers posted on the outside of oil bottles are very misleading. The "winter" weight as the first number is sometimes called being the most misleading.

Example:

Amsoil 20W-50 is LESS viscous at 32*F (0*C) than Motorcraft 5W-50.

Amsoil 10W-40 is MUCH LESS viscous at 32*F (0*C) than Amsoil 20W-50.

I do not use cruise control on hilly roads. I lift before I crest a hill and I coast most of the downhill side. I rarely pull any boost and try to pull vacuum as much as I can when I drive.

This is where you are gaining the mpg difference. I let cruise control do it's thing. My dad told me I shouldn't, but i still do. He always kept his foot consistent on the pedal and didn't increase throttle to stabilize speed on steeper up grades.