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Sacrificing Sidewall Flex For Grip?

White GTS-T
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White GTS-T Mentor

White GTS-T

Posted
Posted

Firstly, i know this is in the wrong section but i need an answer by tomorrow and there was only one person reading the suspension, breaking and tyres thread.

I'm buying new tyres tomorrow and i want to know if fitting a 225/50/R16 tyre on stock 6" wide R32 GTS-T wheels is overkill?

Will i get more grip or just more sidewall flex as apposed to a 205/55/R16 tyre which are fitted at the moment?

Should i just stick with the 205's?

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https://www.sau.com.au/forums/topic/178383-sacrificing-sidewall-flex-for-grip/
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mad082 Grand Master

mad082

Posted
Posted

is it going to be for track drag use? if yes then go the 225's. is street/track then go 205's or 215's. i ran 225's on my stock 33 wheels and didn't really notice a difference. they gripped a bit better and didn't really notice any sidewall flex when cornering, but that was only street use.

700HP-GTR33 Mentor

700HP-GTR33

Posted
Posted
Firstly, i know this is in the wrong section but i need an answer by tomorrow and there was only one person reading the suspension, breaking and tyres thread.

I'm buying new tyres tomorrow and i want to know if fitting a 225/50/R16 tyre on stock 6" wide R32 GTS-T wheels is overkill?

Will i get more grip or just more sidewall flex as apposed to a 205/55/R16 tyre which are fitted at the moment?

Should i just stick with the 205's?

225 tyres will be to large for any type of track work....unless it is for drag.

205/45/16 are the way to go on 6 Inch rims for your car.....remember wider is not always better.

EDITED..Sorry..I meant 205/55/16..Cheers

--------------------------------------------------

Your side walls will hold in corners with this size.

Also if you forget to pump up your tyres and run lower pressure for a while with the 225's your side wall corner tread

will wear quickly and you will have to run...high pressures after to try and even them out.

Don't forget also...some tyre manufacturers under state the widths..so also depends on the make.

Thunderbolt Rising Star

Thunderbolt

Posted
Posted (edited)

I've had some weird and wacky combinations in the past on my car. For a long time I was running 215/60/15 on the stock SR rims (5.5"). The tyres looked very bulgy, but did quite a few mountain drives / skid pan sessions and never had a big problem with flex plus the grip was amazing.

I am now running 225/50/16 on R32 rims on the arse end, and it does not look nearly as bulgy as the above combination was. I am going to give it a go at the track next weekend as two of my semi-slicks have had it and the other two tyres that I have aren't nearly grippy enough.

ps. If you go to this site: http://www.1010tires.com/TireSizeCalculator.asp and type in the two tyres sizes you are comparing, you will see that the 225/50/16 combination is recommended for rims that are 6-8.5" wide.

Edited by Thunderbolt
mad082 Grand Master

mad082

Posted
Posted

you could always try and get yourself a set of 300zx rims. they are about a 7.5" rim, so you could run 225/50/16s and not worry about flex.

205/45/16 are the way to go on 6 Inch rims for your car.....remember wider is not always better.

you would also have to take into account what the track is like. if it is rough the smaller sidewall of these tyres is going to make it rougher, and it will alter your gearing slightly, since the stock size has a higher profile, at 55.

at the end of the day tyre compund is going to have the biggest affect on grip. if you get a set of hard tyres they won't grip as well as a set of sticky tyres. a set of 195 semi slicks will out perform crappy, hard 245's.

foznice Veteran

foznice

Posted
Posted

I'm running 225's all round at the moment, and prior to that, was running 205's all round.

The launching traction was noticeable but the sidewall flex pissed me off when in the twisties. I'm going to run 205's on the front and 225's on the rear next time.

260DET Experienced

260DET

Posted
Posted

For circuit work you need to know the actual tread width of the tyre, not the numbers, in order to make an informed choice. Rim width should equal or be up to 30mm wider than the tread width.

White GTS-T Mentor

White GTS-T

Posted
  • Author
Posted

Hey guys, thanks for the replies.

I should have specified that the tyres were for the rear only. I had previously ran 205's on the front and 225's on the rear but decided this time to go with 205's all round.

I ended up buying Continental Tyres. Has anyone else used these before? I was a bit sceptical as i haden't heard alot about them but they are of excellent quality and cars such as BMW and Mercedes come with them fitted from factory. They're very big in europe.

They were $285 a tyre, marked down to $185 each on special and i got a deal so i got them for $175 each or $350 for both.

I mentioned sidewall flex in terms of drifting. I'm hoping to enter in a Winton practice day the one after the kamakazi battle. I have a set of old 205's and a set of old 225's so i will be able to find out first hand the amonut of sidewall flex i do get if any.

Cheers.

Habler Rising Star

Habler

Posted
Posted

Those Continentals looked perfect fit in 205's.... I dont think there was any real issue when you were running 225's on the rear for the street but when you go to winton i would just be using the 205's.

From my personel experince stretching the tyre just a bit (235 on a 9" rim) made a noticable difference from my street 255's. It felt much nicer overall. I would like to test a 225 on my 9" but the 235's are so easy and cheap to get my hands on.

Also different tyre brands vary so much - 235 bridgestone is more stretched than say a 235 nankang etc. for example

Might be worth trying a 195, 205 and a 225 before the track day to see what feels right?

Or buying some wider rims :(

Thunderbolt Rising Star

Thunderbolt

Posted
Posted

Well I thought I would give some feedback after running 225/50/16 on the rear of the car on the track today. I didn't notice any flex at all, however the tyres didn't grip as nicely as I would have liked. It was probably made more noticeable because I was running semi-slicks at the front.

Sticky Collaborator

Sticky

Posted
Posted

depends on brand....

some brand will have a stiff enough sidewall that it wont matter, whereas some are really soft and allow the tyre to move more.

but its better to have a correct sized tyre. so 205 is a better fit.

  • 1 month later...
Birth Experienced

Birth

Posted
Posted

This may seem silly. What is the difference in profile between 50 / 55 / etc? Does a bigger number mean that the verticle height of the tyre is higher? Does a smaller number mean that the overall diameter of the tyre is smaller?

Duncan Grand Master

Duncan

Posted
Posted

yeah 55 is higher than 50 for the same width, but the even sillier thing is its not 5mm or 5cm or anything like that. It is the height of the sidewall as a % of width.

so a 265/35/18 is about the same height overall as 235/45/17. there are calculators around to calculate equivalent sizes

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