jomcgui

About 22mpg mixed driving

vegas_

Does anyone know how one recalibrates the Speedo (and Odometer) to compensate for a tire size change?

If I lower my car with 20's, then the tires are smaller but wider than the stock tires.

The stock tires have to turn 720 times to cover one mile, but the 20's have to turn about 750 times to cover the same 1 mile.

Since the speedo and Odomoter count the number of revolutions of the wheels, not the actual miles driven, the speedo will show slightly more miles driven and the MPG will seem to be slightly higher.

So 29MPG is probably really only 28MPG, but The good news is you will get fewer tickets, becuase if you're speedo indicates 80MPH, then the car is actually going 77MPH. Unless you use a portable GPS to indicate speed, that should be correct regardless of tire size., but I'm not sure how accurate those are.

railerfan

I get 32 mpg on the highway on my 2013 convertible going 65 mph. Get somewhere around 20 driving in the city.

Nuke

We use the handheld tuner to recalibrate the speedometer for tire size changes, gears, etc. Just because you go to a 20" wheel (which I prefer not to due to the increase in rotational mass and reduction in sidewall = harsh ride) you may not need to adjust the speedo since your tire size choice can keep you as close as possible to the stock tire O.D.

joihan777

'12 V6 Premium Convertible.

35 mpg hwy top up @ 55 mph no wind.

31 mpg hwy top up @ 65 mph no wind.

23 mpg 1/2 city & 1/2 hwy.

Bone stock except for a cell phone mount built into Sync radio.

Murgatroy

2013 V6 base. Automatic. 17" Michelins. Base 2.73 geared rear.

I do a 65 mile commute, 50miles of it on the interstate.

I am holding a 25MPG average for the 1100 miles she has on her.

I cruise at 75MPH.

I will admit that she could (and has) get better mileage, but I have issues keeping my foot out of it.

I do like the fact that she cruises under 2k RPM. I don't like the fact it takes a full second to shift to third for an overtake.

I think a tuner will be the first modification she sees.

rt66er

2013 V6 Pony Package (18-inch wheels) Automatic, 2.73 gears, Bama tune. First full tank calculated 24.40 mpg. I would break that down as about 50% rural highway (60 mph) 30% interstate (75 mph) and 20% city. Of course, the car has less than 700 miles on it at this point; I expect mileage to improve a bit after it gets a few more miles on it.

2011V6Nicole

2011 manual
Most of my driving is city driving and short distances (my house to school 15 mins away). With a steeda CAI and the bama 93 race tune on it i've been averaging 15-16. Could be much better but I have problems keeping my foot out of it haha.

Nuke

Considering where you're driving, that your car just about hits operating temperature (maybe) by the time you get to your destination and your problems with your foot, I'd say 15-16 MPG is doing pretty good.

amyhughes

How accurate is the dash display? It tells me I'm getting about 22 with mostly short-distance suburban driving, so I'm driving it mostly cold. 2013 V6 Premium, Pony Package (18-inch wheels), Automatic. On a 1.5hr highway trip at 75mph it only got up to 24. 6200 miles on the odometer.

I'll calculate using gas purchases starting with the next fill-up.