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Hi Guys, sorry to bring up an old topic.... Been doing heaps of research in the past few days.. but I don't have straight answers..to the following

What's the best wheel/tyre size for the V coupe against common tyre sizes (which means best range of rubber at better prices.. )

Currently running FR 245/30 R20, 275/30 R20 ... want to go down to either 18/19s"... Love to keep the same 275 on the rears....

Edited by rs88
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https://www.sau.com.au/forums/topic/417393-best-tyrewheel-sizes-for-handling/
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Yeah I know.. that thread has more on 20"s...

However.. for example.. dropping to 18's and using a wheel calculator I have to change to 275/40-18 which would give me the following: d=26.66 w=4.33 +0.62%

Then the questions that I don't have answers are

1) 40 vs 30 for sidewall - is that enough? or still too little? Should I be looking at 45s?

2) Is this tyre size 275/40 18 common enough for both price and variety?

3) Or... I have to bite the bullet and go for less wide?

http://www.skylinesa...of-the-v-coupe/

Read this ???

18 would be best

lol - rs88 started that thread!

what are you trying to do with your car, rs88?

do you want to track it and cut down lap times or do you just want a nice street car that you can tip into a corner every now and then?

are looks more important to you than function?

and how much you're prepared to spend.

The answer to those 3 questions will hugely change the recommendation - there are so many variables beyond diameter - there is width, weight, tyre selection, and all those will be restricted by the final variable: the size of your bank account.

what are you trying to do with your car, rs88?

do you want to track it and cut down lap times or do you just want a nice street car that you can tip into a corner every now and then?

are looks more important to you than function?

and how much you're prepared to spend.

The answer to those 3 questions will hugely change the recommendation - there are so many variables beyond diameter - there is width, weight, tyre selection, and all those will be restricted by the final variable: the size of your bank account.

QFT.

OP - Do not pass go, do not collect $200 until you have answered this.

rofl! you guys r funny! thanks for the responses btw..

ok... after much **soul searching** .. its going to be a street car with occasional corners .. 30/70 between looks/handling ..

If I keep 20"s, upgrade Rears to good tyres - it will still be skittish on country roads, cheaper short term..

If I downgrade to 18"s.. I get access to better tyres ... $$$ on the short term..

Of course "how long is a piece of string" ... but I've trying to work out a budget .. thus this thread about best wheel size against common tyres for prices.. then I can start looking / comparing..

I would love Rays wheels.. but I think that would be out of my price range.. hard to get CFO approval on this!

just tell me how much you want to spend and we can help you.

I've bought and sold 20+ sets of rims in my time, from 17 inch starcorp chromies to $$$ lightweight racing wheels. I've been learnt and burnt enough times to be able to help.

I can tell that you don't want to keep the 20's, and spending money on upgrading the tyres now is just going to cost you more in the long run when you give up and want to replace them with a different wheel.

so lets get a ball park dollar figure and start talking options.

Edited by SMOKEYC34

Firstly I would like to say, there is no such thing as a "Best" tyre and wheel sizes for handling. As Smokey mentioned, there are too many variables for there to be a BEST combination. However, what you should be asking is, the most optimal tyre and wheel size to improve handling. I would say this is between a set of 18s and 19s. Tire sizes and prices vary slightly between 18s and 19s and more for 20s. I have found anything from a 225 to 245 for the fronts and 245 to 275 for the rears comfortably improve body roll compared to factory specs.

Next thing you got to figure out is do you have heavy 18s or lighweight 19s? Unsprung weight affects this as well. Then you will need to determine your suspension and ride height...stock or lowered?

If you are not after record breaking times around the track then I would suggest a decent brand tire + lightweight JDM rims + slightly lowered + sway bars. These mods alone will give you a pretty noticeable improvement over factory.

I reckon even the 18's aren't optimum for handling... Personally I would go down to 17's if I was going for aftermarket wheels (yes, you need decent offset to clear the brembo brakes)

I'm back on the stock 17s and they clear Brembos, by about a bee's dick.

But 17s look ways to small, and 18s still look borderline IMO. These cars have big arches to fill. 19s or bust I reckon.

Hmm.. ok.. Thanks. what about Sidewall.. what's a good compromise .. 35 on 19s? or 45 on 18s?

I will be looking for second hand rims at this stage... budget atm $1000 ( i know that's low .. ) .. too early in the year..

Sidewall is obviously dependent on width.

Use you std rolling diameter as a guide, but I've got 40 profiles on 19s, and am satisfied with the ride/handling balance.

18s 45 is good. You have to weigh up tyre options too, some niche sizes are very expensive, comapred to something a tiny bit different that will have a much larger range of options.

Thanks PN-Mad.. you hit the nail on the head! That's the reason for this thread.. to find out best combination of width/height/size vs common tyre sizes

I know about the rolling diameter/aspect ratio .. but what I don't have is experience.... I haven't played around with different size wheels and tyres to have a "feel" for what's good against theory .. and of course.. no knowledge of tyre prices.. unless I know what I'm looking for ...

With that in mind I can more or less know how to budget for a really good tyre and then start looking for rims in that size..

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