OMG My Gas Mileage!!! General Question Need Everyones Help

[kpaske]

Right, what VehiGAZ said - and most importantly, understand what iamjacksadrenalgland mentioned about having larger than stock tires - even if you are doing perfect calculations, your data is inaccurate because larger tires throw off your speedo/odo, so it may appear that you are getting much worse mileage than you actually are.

I've got 33" tires on 16" wheels, and I estimate that my speedo/odo are off by about 10%. Adjusting for that difference, I probably get 12-15 MPG on average.

[nfpgasmask]

I just ordered Tone's scan guage. I have never used a scan guage before so now I am wondering if it will give me accurate MPG calculations....we shall see. I'm really bad at math so I could use the help....

All I know is that when I get on the open road and drive for 2 hours at 85-95 MPH my VX CHUGS gas.

Bart

[Tone]

You'll need to use something like the miata garage tire calculator if you have changed tire size to see what percentage your speedo is off and then you can set the ScanGauge to take that percentage into it's calculations. I use MPH display of the SG on the dash of the '55 since I've gone to a taller tire. Keep the air pressure at max in the tires and drive conservatively but it is what it is and if you need MPG, this the WRONG vehicle.

BTW, stock tires are almost identical height/diameter on the 16" and 18". Come on guys, don't post INCORRECT information, it just confuses the newbies. Now the 18" rims could be heavier but I would not expect more than a few pounds - anybody have those specs? And if so, that would be more of an onroad handling issue when pushed.

1999 245/70/16 Diameter 29.5", 6.8" sidewall height (comfortable)
2000/01 245/60/18 Dia. 29.6", 5.8" sidewall height (less flex)

And yes, the wheels are interchangeable between ALL years.

[JHarris1385]

Hey Lizard, did you ever get your gas mileage back up?

I am sufferin too. I get max avg 14mpg.
Im about to make a post about it though cuase of me CEL code.