Cool Rims, Bad MPG???

Jeff, running out of gas is unlikely to affect your fuel economy, but you will definitely take a hit from the larger rims, and a second hit from the new tires. Not much you can do about the rims, but putting some miles on the tires will eventually improve your fuel economy. You might want to check your tire pressure as well.

 

Sadly, in this case COOL COSTS!!! The extra weight of the new rims, etc all add up to ding the MPG. As far as the trim rings I chucked mine at about 750 miles, did not notice any mileage hit. Tough choice!

 

One more thing to consider: the diameter of your new wheels is probably bigger than the stock wheels, so while new tires (probably wider too) will cost you MPG, it might not be as much as it seems.

Your MPG displayed on the screen is derived from the amount of time the fuel injectors are open (for fuel measure) and the number of wheel revolutions (based on the stock wheel/tire with 855 revs per mile.)

Hunt around in the menus on the display and I think there's a recalibrate button for when you change your tires. That may help some.

 

.... as you've heard.. yes..

my question to you. what ratio are your wheels? my tire has a 45 ratio which puts it near stock size. a 50 ratio would give you an larger with stock radius while your speedometer will be off making your gas mileage read lower since it's having to move farther with each turn of the wheel.

while i see high 30's and low 40's... heavier rims and fatter tires will leave you in the 30's.

... long open road trips at 70mph+ with a car full of camping gear and two people... with two bikes on a rear hitch get you 29mpg...

a misfiring cylinder will get you 29mpg too...

 

I used to be a BMW guy and I loved my 19" stock sport rims on my 645. When I did a 180 and got my Prius, I was jumping for joy when I got a look at the price of tire replacements compared to what I was used to: $70 each instead of over $200!!!
Now I love my small wheels!

 

Yup, cool rims that are heavier than stock or raise your overall diamter from stock (tire choice is critical) will change your milage and usually for the worse unless you put a lot of thought and money into your choice.

I regularly drop about 4-6mpg or more from the stock combo to my 17" combo. I see less of a change vs my stock rims and aftermarket tires but it is a negative hit nonetheless.

It's the price you pay to be cool