Installing Aftermarket Wheels on the c

Following up from my previous 2 threads on wheels...

http://priuschat.com/forums/prius-c-main-forum/105235-prius-c-steel-wheel-specs.html

http://priuschat.com/forums/prius-c-accessories-modifications/105927-test-fit-wheels-prius-c-5.html

First off, the main driving force to change out the wheels was for aesthetics... the wife hated the stock wheels and it's her car. So, armed with the okay to upgrade, I went and searched for suitable wheels for the c. My main considerations were reasonable price, light weight and of course a wheel that appealed to both my wife and I. I settled on some 6.5x15 40ET Konig Helium rims. I have used this rim on other cars and have been impressed with their quality, light weight and reasonable cost. That they are a direct knockoff of a Volk CE28 isn't necessary a bad thing, either.

In preparation of the wheels after ordering, I had the stock tires dismounted from the steel wheels. My plan was to use the TPMS from the steel wheels in the new alloys. Here are some photos on how to remove the sensor from the steel wheel.



















The rims arrived and of course only one of the boxes of two shows up. Never mind... I quickly unpack the rims and have them taken to the shop to have the stock 175/65-15 tires mounted. I had some doubts if these would even mount on the rims without problems due to the new wheel's added 1.5" width, so I wanted to know right away if there were going to be any problems as soon as possible.



Some hubcentric rings to mate the rims to the Prius c centerbore.These are needed to center the wheel on the mounting surface to eliminate any dynamic vibrations due to the rim being off center.









I needed to check to see if the TPMS sensors were going to work with the new rims, so I do a quick test fit and find... that they will not work with the new rims.

stock rim and how the sensor should lay in the rim...



and how the sensor sits when mounted in the alloys...



I decide not to mount the sensors in the wheels as they stick up too high above the surface that the tire bead sits on and have heard how sensors have been broken when tires are mounted. With these sticking up this high, it's just and invitation for a broken sensor.

pic of the width difference between the 5" stock rim and 6.5" rims.



again, weight of the stock 5x15 steel rim...



and weight of the 6.5x15 rim being installed...





Finally take the rims off to have the tires installed and this is the combined weight of the rim and tire...



Some pics of a 175/65-15 tire mounted on a 6.5x15 ET 40 rim...









While not ideal, I feel the tire will work fine with the rim. I'll run it and if there are problems down the line, will purchase some 185/50-15 tires for the added tread width.

 

Got the second set of wheels in and had the tires mounted.



Installed the hubcentric rings into the rims...





and mounted the rims/tires to the car. see how the hubcentric ring fits perfectly over the stock toyota brake hub bore?



Mounted the rims and torqued the lugs to 90ft/lbs.



One added note for those looking for rims, make sure the centercaps allow for protrusions as the front axle sticks out past the rim as shown in the picture above. There have been others that are having problems with flat type centercaps.



and some shots of the completed job...







Based on the test fit earlier, the wheels have the same offset and width of the test fit wheels. The tires are skinnier than the 190/60 tires that were on the white wheels, so based on that I expect no interference problems with this wheel and tire combo. Also, the wheel tire combo weighs 28 lbs some 5lbs less than the stock steel wheel and tire I weighed earlier.

Seeing that I'm using the same stock tire, but a wider, lighter rim, I want to see 1) how much difference does a lighter rim make in terms of mpg, 2) how does only increasing the rim width affect handling... the stock wheels and tire combo was not very reassuring and was easily overdriven during a canyon run, and 3) how does a 175 tire do on a 6.5" rim.

Hope this step by step DIY helps the members here. If you have any questions, post them up... happy to help, if I can. Also, if you would like to see more pics of the journey of my c, they can be seen in my album, here...

https://picasaweb.google.com/kkim993/PriusC

I'll be sure to take some better pics once the rain stops.

Aloha,
Kelly
:nerd:

 

not what I wanted to hear, but will stay with the 175 until a problem surfaces.

Your car looks good with your rim choice. What do they weigh?

 

the low pressure light will be "on" on your dash.

 

1- My guess is that it doesn't look like it. notice how flat the centercap is, which is exactly like how the centercaps on the white wheels used for test fitting were.

2- that's a great question to ask Tire Rack. They are very knowledgeable and their expertise should be used before you purchase any wheel from them.

 

It's only been a few days, so I can't accurately comment on all your questions. The car now feels nimble and light like it was with the stock steel wheels and the 175 tires. When I had switched the car to the test fit white wheels, there was a lot more grip in turns and the car felt very stable, compared to stock, however MPG w/ the white wheels took a hit of about 10%, depending on where the car was driven.

After installing the new wheels with the 175 tires, it steers like it did with the stock setup and while it is not as stable feeling as the white wheel setup, it is more stable than the stock steel wheels. The extra width seems to have helped in that respect.

My wife just drove the car to work this morning, which we have been using as our "test" to see how the changes that are made are affecting the car. She is by no means a car enthusiast and her feedback is very important and unbiased due to her not really understanding what should be expected with each change. Her commute this morning was 68 MPG to work, which is a few MPG higher than she ever was able to get with the stock setup. With the white wheels, she was unable to hit 60MPG and more likely returned in the mid 50s.

The real test will be her commute back home. With the stock wheels, she was getting about 55mpg. With the white wheels, she saw trips as low as 49, but more so around the low 50s.

Her feedback with the new wheels and 175 tires is that the car is not as stable as the white wheels 195 setup, but it drives better than the stock setup. I've lowered the front tire pressure from 40 psi to 36 in hopes to get the ride a bit more comfortable. At 40f/36r psi, the new wheel/tire setup was considerably rougher riding than either of the previous 2 setups. She likes the ride now at 36f/35r psi. We'll see what type of MPG figures we can get with those pressures.

I've setup the trip B meter to record everything after the new wheels were installed. I also recorded trip A settings which were entirely on the white wheels. I should have better/clearer picture of what's going on after more miles are recorded.