Upsizing Alloy Wheels, Pros & Cons?


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Plus-Sizing

yes they have to. bigger tire means lesser rotation comparitively.
Why not try the Plus-Sizing concept?

IMHO, this is the cleanest way to upsizing your tires without worrying about stressing the suspension components. Originally said to have been developed to counter the effects on the speedo readings caused by changing tire sizes, this method advocates a single upsize to get best results.

To clarify things further, here's an example

Say the company tire size is 155/70/R13 - wherein the Contact patch is 155mm, the Aspect Ratio is 70 and the rim size is 13". According to the Plus-Sizing concept, the ideal upsize would be a 165/65/R13. This would put the minimum stress on the key components while giving a wider contact point for the road.

Guru's please correct me if i'm wrong about this.

Cheers [thumbsup]
 
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To clarify things further, here's an example

Say the company tire size is 155/70/R13 - wherein the Contact patch is 155mm, the Aspect Ratio is 70 and the rim size is 13". According to the Plus-Sizing concept, the ideal upsize would be a 165/65/R13. This would put the minimum stress on the key components while giving a wider contact point for the road.

Guru's please correct me if i'm wrong about this.

Cheers [thumbsup]
Correct. Speedo calibration depends on the "Overall Diameter" which is proportional to how much the wheel rotates.

Example is 165/80 R14 to 185/70 R14 where the OD changes from 24.39" to 24.19"
 
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:help:Guys, I have a doubt. Since tyre upsize causes incorrect speedo readings, do manufacturers apply corrections across different variants of their cars?

Eg. Punto has 165/80 R14 for lower variants and 195/80 R15 for the top end. Will they have the same speedo readings at the same speed?
The top end OE size is 195/60 R14, which is almost same as lower variants of 165/80 R14.

Normally, the wheel sizes of any car will be same and no need for any corrections.
 
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I think a lot of you have got it wrong. The basic funda of upsizing is that the overall circumference of the tyre should remain the same (+/- 2%). You can easily check this using the tyre size calculator. If you are increasing the size of the rims, the tyre profile has to reduce.
Actually there is no extra stress on any components if the tyres are reasonably upsized. In fact most Indian cars are undertyred (downsized & poor quality tyres) to cut costs. The easiest way to check the ideal upsize is to look at the spec sheet of the European version of the same car.
 
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One query regarding alloys for my i10.

To save money n to save on warranty issues, I am seriously thinking of putting getz gls 13" rims, 4.5J so that I can plonk in 175/70 R13 tires on them.

Is it the right thing to do or should I go in for alloys of 13" 5.5J only?

Suggestions awaited as I plan to do this tomorrow.
 
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One query regarding alloys for my i10.

To save money n to save on warranty issues, I am seriously thinking of putting getz gls 13" rims, 4.5J so that I can plonk in 175/70 R13 tires on them.

Is it the right thing to do or should I go in for alloys of 13" 5.5J only?

Suggestions awaited as I plan to do this tomorrow.
Amiti,

You can fit 175/70 R13 in 4.5J rims. I'm using 175/70 R13 on 4.5J Hyundai OE alloys for the last 18k kms without any issues.

Your recommended choices

165/80 R13 83T 4.5J

175/70 R13 82T 5.0J

185/70 R14 88T 5.5J
Zinam, 165/80 R13 and 185/70 R14 will be too tall and will touch the inner sides of the wheel well.

For i10, the right upsizes are

in 13"

175/70 R13

in 14"

165/65 R14
175/60 R14
185/60 R14
 
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Thanks Zinam and Para.

I will stick to 13" only.

Para i10 rims are 4B. Hence I need to put alloys as I have no choice. For now I have decided to go for plati alloys 13" with 5J and put in stock tires for at least 7-8 months. Then I will upgrade to Michelin 175/70 R13.

By the way I tested with getz gls rims which are 5J. However they are bit heavy. Hence I think upgrading to 5J alloys will be wise.

Do comment.
 
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Thanks Zinam and Para.

I will stick to 13" only.

Para i10 rims are 4B. Hence I need to put alloys as I have no choice. For now I have decided to go for plati alloys 13" with 5J and put in stock tires for at least 7-8 months. Then I will upgrade to Michelin 175/70 R13.

By the way I tested with getz gls rims which are 5J. However they are bit heavy. Hence I think upgrading to 5J alloys will be wise.

Do comment.
I suggest the other way around. Get the Getz rims and Invest on good tyres. They're life savers.

I don't think the rim will be too heavy. In fact a friend of mine was running on 175/60 R14 with swift's rim which is 14"x5J. I never felt it too heavy.
 
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Point noted para. Decided to go with getz rims 4.5J and michelin 175/70 R13. Getz gls 5J rims felt bit heavy.

Thanks a ton!
 
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Larger tyres & rims surely look good. But i agree i got my swift's steering assembly changed worth 22k under warranty. Thankgod i kept my stock rims & tyres in the store room[clap]
The car's running on 205/55-15, ride is a lil bit rough, tyre noise is high on concrete, but wet & dry traction is brilliant.
 

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