[AlanHo]

This article chronicles the results of trying 15, 16, 17, 18 and 19" wheels on a VW golf test bed.

It confirms the fact that bigger wheels come at the cost of worse economy and comfort

Effects of Upsized Wheels and Tires Tested - Tech Dept. - Car and Driver

[Dazzler]

That's interesting (thanks Alan) 

[The Gonz]

No secret. The fashion for larger rims and associated lower profile tyres has always been for more precise handling at the cost of economy and comfort.

[Dazzler]

I'm doing a good job then to pretty much match the official combined ADR fuel figures for my Calais with 19" wheels.

You can combat the fuel usage by using lightweight forged rims and sticking as close as possible to the original width, comfort will always be reduced somewhat unless you have the suspension re-tuned to your liking.

[xiziz]

Nice to have some numbers on this, good find! Shame they didn't use alloy 15" too, would have liked to seen the difference between them and 16". I was thinking of swapping my 16" for 15" when time comes to replace them, looks like about 2% fuel savings per inch less.

[Dazzler]

Nice to have some numbers on this, good find! Shame they didn't use alloy 15" too, would have liked to seen the difference between them and 16". I was thinking of swapping my 16" for 15" when time comes to replace them, looks like about 2% fuel savings per inch less.

Appearance has to come into it a bit though for most people. I'm one of the tightest people on the planet but wouldn't sacrifice the beautiful 19" wheels on my Calais for maybe $5 per week in fuel...

[xiziz]

Nice to have some numbers on this, good find! Shame they didn't use alloy 15" too, would have liked to seen the difference between them and 16". I was thinking of swapping my 16" for 15" when time comes to replace them, looks like about 2% fuel savings per inch less.

Appearance has to come into it a bit though for most people. I'm one of the tightest people on the planet but wouldn't sacrifice the beautiful 19" wheels on my Calais for maybe $5 per week in fuel...

There always has to be something your prepared to splurge on - otherwise there is no point in being "good with money"
 
I've never been a fan of big rims and skinny tires. I'm a sucker for practicality, and I'd love a set of five spooked easily cleaned rims. Also 195/65's are a lot cheaper(atleast here) than 225/40's, which is probably where the big saving will come in hand. And on our coarse roads the extra rubber is pretty comfortable.

Your Holden can pull off the 19" rims, I don't think the I30 can, I30 does looks good on 17".

On the final line I doubt I'll be prepared to spend the money on new rims when I got a perfectly fine set of 16" and 15" each before there thoroughly worn out.

[Doggie 1]

I'm one of the tightest people on the planet but wouldn't sacrifice the beautiful 19" wheels on my Calais for maybe $5 per week in fuel...

    

[Dazzler]

I agree xiziz 16" or 17" is plenty big enough for the i30. My tyres are going to probably be $1000+ when I replace them. Fortunately they are lasting really well. I look like getting 70K+ out of the original set! 

[neptune]

I'm a sucker for fat tyres and big rims.....comes from my youth , playing with muscle cars.........

[The Gonz]

My most ostentatious was Firestone white lettered 235/45 on 14/7 Globe Bathurst polished silver on black with 1" offset. That was impressive on a VH Commodore back in the mid-80s. The rubber was coming out flush with the guards.

Like this but in 5-stud and with smooth centre caps fitted.

[Dazzler]

[Doggie 1]

Same wheel as on my Hairy P.