Advantage/Disadvantage of Plus Zero

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What are the advantage and disadvantage of plus zero tire ?

The OEM size is 205/55-16 the plus zero size is 215/55-16. Aside from 1.7% larger diameter will cause the speedometer reading error of about 1 MPH at speed of 65 MPH.

I think the recommended is do not excess 5% when do the plus zero sizing.
 
The advantage would be better handling with slightly less ride quality. Also another reason one would make a change to a tire size that is nearly the same would be related to tire availability and pricing.
 
Originally Posted By: beast3300
The advantage would be better handling with slightly less ride quality. Also another reason one would make a change to a tire size that is nearly the same would be related to tire availability and pricing.


This. Our Fit has a nearly impossible to find 185/55-16 size as OEM. +0 sizing to a 205/50-16 offers many more choices.
 
Disadvantage is that the wider cross section may cause more rolling resistance. Your speedometer and odometer may be off, causing issues. But the 215/55-16 to me is a pretty optimum size for most vehicles, and is fairly common.
 
Originally Posted By: HTSS_TR
What are the advantage and disadvantage of plus zero tire ?

The OEM size is 205/55-16 the plus zero size is 215/55-16. Aside from 1.7% larger diameter will cause the speedometer reading error of about 1 MPH at speed of 65 MPH.

I think the recommended is do not excess 5% when do the plus zero sizing.


First I think a "Plus-Zero" means you go wider by one increment, and down in aspect ratio by one increment. So a 205/55R16 is Plus-Zero sized to 215/50R16. When I do the math, that comes closer than the suggested sizing (1.66% smaller vs 1.74% larger)

Given that definition, the advantage would be putting more rubber on the road - better dry traction, better wet grip, better handling. The disadvantage would be higher rolling resistance, worse hydroplaning resistance, worse snow traction. worse ride.

- BUT -

There are larger differences between tires (meaning make and model) than there are between the same tire in a different size. So I think careful selection is way more important - particularly in a popular size - which a 205/55R16 is.

And I have heard that no more than 3% rolling diameter difference is what you want. I have heard that some folks have had issues when they went outside that range.
 
Also different tires put substantially wider or narrower contact patches on the road even if they are labeled the same size.
Most snow tires have a narrower contact patch even if they are same size.
I did a minus zero on the focus for snows and didn't regret it at all, 195/60R15 to 185/65R15, which give a fraction more ground clearance, a slight gearing reduction, and a narrower contact patch. I might do the same when it comes time to replace the 3 season tires and go for a low rolling resistance tire to increase mileage.
 
Originally Posted By: bourne
Try 225/50R16 as well .


Exactly!
The 225-50-16(22.85") is the closest diameter match for the 205-55-16(22.87") if they'll fit in the wheel well with out hitting the shocks/struts.

I have found some 205-55-16 that are really super sized in terms of width compared to some other 205's. The Pirelli P7's. Man do they look good!
 
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I replaced the 205/55R16s on my old Sunfire GT with 225/50R16s, and it made a pretty marked difference. They just barely fit on the 6" wide rims. The rolling diameter was almost identical, so no speedometer or odometer issues.
 
I think 225/50-16 needs 7" wheel width to have decent performance/handling, 6" wheel is just to narrow for it.

The tire is for 2006 Volvo V70, what I was looking for is slightly softer ride because it is my daughter's car and she drives very conservative. I think increasing the aspect ratio by 5% (205/60-16) the sidewall increases by 0.4" and the rolling diameter increases 3.2%, which is too much.

Keeping the same aspect ratio of 55% but increase the width by 10 mm will increase the sidewall by 0.2" and the rolling diameter increases 1.7% which is small enough.

Another option is 195/60-16, 10 mm narrower but sidewall increase by 0.15" and the rolling diameter increases 1.3% which is less than 215/55-16.

I used the wrong term, from 205/55-16 to 215/55-16 is not plus zero, it's more like 1 size larger.
 
Thanks CapriRacer,

Your inputs are always appreciated, by me and many others on the board.

I agree that the biggest benefits in term of performance/handling, ride and noise, tread life ... are huge between brands/models.

As I posted above, the tire I'm looking to replace this Fall is for 2006 Volvo V70 station wagon, it's driven mostly by my daughter and she is very conservative driver, she drives like a great grandma. When we drove home from San Diego where we bought the car, the traffic flowed at around 70-80 MPH and I drove slow at 64-66 MPH on right lane for her to follow, she barely kept up with me. When she changed direction, either turn right or left, she slowed down to around 10-15 MPH.

The way she drives it doesn't make sense to buy high performance tire, I'm looking for softer ride and quiet tire for her. I think by going up 1 size from 205 to 215 it may give the car a better/softer ride.
 
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I think increasing the aspect ratio, 55 to 60, the height of the sidewall, will have more impact on the "softer ride" than a wider tread, 205 to 215.
Wider tread will offer more grip as explained by CapriRacer...

As for the effect increased overall tire size has on speedometer reading (and odometer too)....the difference MAY be beneficial.
When I did so on the Camry (205/65/15 to 215/55/17), the speedo became MORE ACCURATE by 1mph, from being off by +3 to being closer to +2mph at any speed.
...BUT the odometer is now off by -2.5%, i.e. 100 miles on the odometer is really 102-103....not the worst impact.

As CapriRacer stressed, selecting a DIFFERENT tire, brand and model, will have greater impact on the parameters you're interested in pursuing.

You say you don't need "high performance" tires...WRONG. EVERYone needs the best tires for the worst conditions on which they will roll....for me in Florida it's wet road/thunderboomer conditions, i.e.a wet traction tire capable of high degree of water dispersion/high resistance to hydroplaning.

The OEM-spec tire originally on the car would slip off stops in the rain, a common occurrence where water floats on oil drops collected at lights/stop signs, and on freezing rain conditions (okay NOT a common occurrence in Florida, but experienced last fall in Chicago area)...

The new tread, Hankook Ventus V4 ES tires are like glue in the rain under all condition and stresses...I feel amazingly safe on these tires. They are noisier, caused by that grip to the shell-imbedded road surfaces here in Florida, but it's a small price to pay for safety.

Finally, keep in mind the specifications required by Volvo...you really SHOULD keep to the MINIMUM speed and load bearing ratings....many tire dealers will not even mount tires that fall below those ratings...

So as CapriRacer suggested, do your research, HTSS_TR, for a brand/model tire and not just changing tire size.
 
How many years of driving experience does your daughter have?
Could her driving style change when she gets more familiar with car or has more experience?

Krzys
 
I increased the aspect ratio of my P5 tires recently from 195/50/16 to 195/55/16. The increase was over 3%

Given the built in bias of the speedometer to read higher actually improved the accuracy of the speedo.

Let's face it, at 60 MPH, a 3.x percent is around 2 MPH. It's really not a issue.

On the other hand, I'm not so sure there is that much difference in the ride either. I chose the tire because 195/50/16 is a rare size, making what few choices I had, more costly. Going to the 195/55/16 size provided more choices and more pricing options.

The P5 specifies V rated tires, so I couldn't just look for a value priced H rated tire without expecting a fight.

I ended up with the Pirelli Cinturato P7 from Sam's club. With the $70 off a set of four, it was under $600 for the set installed, including about 8% sales tax and state fees.

Pirelli CINTURATO P7 195/55R16 87V 4 $133.32
Premium Tire Install Package 4 $15.00
Sales Tax: $41.86
Product Fees: $10.00
Instant Savings Applied: $70.00
Grand Total: $575.14


These will probably last until I retire the car as I now have 160K miles on her.
 
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