[Edju]

jsten,
The new wheels look very nice. And I don't think you can go wrong with the set-up you've described. ELR uses 245/40R-20 size. This page doesn't show the details of wheel offset:
http://media.gm.com/media/us/en/gm/.../Jan/13naias/elr/0115_elr_specifications.html

I'm surprised the ELR wheels are not forged wheels as Volt wheels are. I've been very happy with ELR's range so far - I've had it for 3 weeks and ~1,500 miles on the odometer, and I'm already seeing 52 ~ 53 miles per charge (driver only, no A/C use).

 

[Mister Dave]

I like it.

 

[Bavarian13]

Looks outstanding.

Keen to hear about the relative comfort (and range, of course).

 

[cmr]

very nice!

 

[rubley]

Looks nice!

 

[CaptiainSlow]

My question is why? Why 20" wheels and Conti tires? Conti tires don't do anything great but don't do anything horribly. Why 20" vs 19 or 18?

Not a criticism in the least just wondering about the the underlying facts influencing your decisions.

 

[Nuclearboy]

Agree with others. This looks good.

 

[Steverino]

I would never do it, but they do look very nice.

 

[Jim in Tucson]

Looks good. Please report back after 1,000 miles or so and give us a review on the tire/wheel combo.

 

[rdunniii]

I used 235 35 20 tires because they have a close circumference to the stock tires. With the 245s your speedo is going to be off by 8-10% (when your speedo says 65 you'll be doing 70+). But the car will stick to the road sooooo much better than the stock tires, as good as the ELR in my opinion.

 

[ampera_jed]

But the car will stick to the road sooooo much better than the stock tires, as good as the ELR in my opinion.

Will it? Why?

 

[jsten]

Thanks for all of the feedback. The first question that I've heard is "why do it". Customizing cars is 100% personal preference. I'm a 90's car customizer gone green. The wider stance with a lower amount flexible rubber also helps improve handling, especially when cornering.

When choosing wheels, the typical standard max wheel upsize is called a Plus 3. That means you would purchase a wheel that is 3 inches larger in diameter than the original factory size, as a typical max. Usually going higher than that will result in a tire size that is extremely thin because the primary objective is to ensure that the overall diameter of the new configuration is the same as the factory configuration.

Regarding the speedometer accuracy. This is purely a matter of circumference. The percentage difference in the circumference directly reflects the percentage difference in speedo accuracy. The circumference of the factory configuration measures 2099.5 mm while the configuration that I have chosen measures 2134.7 mm. This results in a 1.7% increase compared to factory specs. Therefore, my car will travel 1.7% faster than factory specs. When my speedo reads 60 MPH, I will actually be traveling 61 MPH. I can live with that. For speedo accuracy, an almost perfect configuration is 235/35-20 and the most accurate tire for the Volt running on 20s is 225/35-20. However, I wanted a little more width and a little more rubber around my wheels.

Thanks for all of the feedback.

 

[DAFTEK]

Thanks for all of the feedback. The first question that I've heard is "why do it". Customizing cars is 100% personal preference. I'm a 90's car customizer gone green. The wider stance with a lower amount flexible rubber also helps improve handling, especially when cornering.

When choosing wheels, the typical standard max wheel upsize is called a Plus 3. That means you would purchase a wheel that is 3 inches larger in diameter than the original factory size, as a typical max. Usually going higher than that will result in a tire size that is extremely thin because the primary objective is to ensure that the overall diameter of the new configuration is the same as the factory configuration.

Regarding the speedometer accuracy. This is purely a matter of circumference. The percentage difference in the circumference directly reflects the percentage difference in speedo accuracy. The circumference of the factory configuration measures 2099.5 mm while the configuration that I have chosen measures 2134.7 mm. This results in a 1.7% increase compared to factory specs. Therefore, my car will travel 1.7% faster than factory specs. When my speedo reads 60 MPH, I will actually be traveling 61 MPH. I can live with that. For speedo accuracy, an almost perfect configuration is 235/35-20 and the most accurate tire for the Volt running on 20s is 225/35-20. However, I wanted a little more width and a little more rubber around my wheels.

Thanks for all of the feedback.

I'm also a 70'80'90'20' mod guy gone green myself. Welcome to the club brother... Your understanding the physics of tire dimensions/weight/mpg/handling is key on and I couldn't have said it better myself. Looks good btw, i really like it...