Today I bought 2 tires in this size, I have 205/50/r16s in the rear.

This is my girlfriend's car but if we're together, I'm driving which is all the time.

The reason I bought these is because of a Craigslist ad. This tire shop is fully stocked on used tires in this size with 70-90% tred, like a huge wall of them so they were $30 each installed and we also drove our last set down to slicks and needed tires for cheap. We got the freshest pair and they look brand new.

I spent about an hour and a half driving today after installation in various conditions of Houston and here is my analysis.

First I'll start with the biggest change: ground clearance. Houston is a territory of failing roads due to poor foundation. There are many potholes and construction sites and temporary road fixes like thick sheets of metal laid on the road. It also is prone to flooding so many driveways have steep banks and the Fit front bumper will rub on most of them even when cutting in at an angle.

So, the added height is beneficial in suppressing road abnormalities and may even provide a crucial amount of height that can prevent flood waters from entering the cab. This has happened once this year already. There isn't any rub in the wheel wells, but we have not loaded it down with full passengers and cargo yet.

Fuel efficiency and aerodynamics.
Now there is a slight rake from front to back since my rear tires are smaller so this does affect my efficiency. However, considering the added rolling resistance from going from slick tires to fully treaded tires, efficiency loss was hardly appearant.

I am a hypermiler driver. I can consistently drive my 1995 Chevy c1500 between 20-21mpgs when it has an EPA estimated 13mpg city/17mpg highway rating. The active MPG gauge on the Fit is what allowed me to carefully analyze the fuel efficiency as I always do when I drive.

In general, my goal is to be at 40mpg or higher as much as possible on the cluster. At 60mph, the car required just little more gas to maintain speed, but is most efficient when traveling between 65-78mph. I was able to maintain a 36.8 mpg average from both highway and urban driving while trying to be curteous and not too slow to other drivers. This is an identical average between 205/55/r16 and stock 205/50/r16 with only a subtle slight change in driving style at 60mph. This is most likely due to a slightly taller gear ratio from increased diameter.
This is considering the raised front end and stock height rear end.

Overall, changes from day to day driving habits and mood will have more impact on your fuel average between fill ups than these larger tires do.

In conclusion, if you are considering installing 205/55/r16 tires, consider my experiences with using the tire to decide if you would like to go ahead with it for whatever reason.

As to handling characteristics, I'm not financially motivated to test this, but understand that the center of gravity will be raised slightly and more likely to make the car roll a little more in the corners.

 

how accurate is your mpg calculation? u have bigger than oem tires which will negatively impact your odometer reading. use GPS to track your mileage.

 

Probably off by a margin no greater than 5%

Good point.

Edit: it's a -3.2% difference in revs/mile and +3.3% difference in diameter.

So instead of 36.8 mpg, I get 35.7 mpg.