What is the point of bigger rims?

[Jarp]

As the title suggests was wondering what advantages/disadvantages larger rims have? As far as I can tell it would seem you can get a little more rubber on the road and less side wall flex with larger rims and then lower profile tyres but on the other hand you add more mass to get rolling and increased cost of tyres (not to mention the rims) and potentialy reduce ride comfort on rough roads. Opinions?

PS The way it looks is not part of this question as asthetic appeal is in the eye of the beholder not because Giavani thinks it's "sic mate".

 

[nathanVY]

Nothing but disadvantages really, lower profile, less traction, reduce ride quality, more expensive tyres, etc, etc.

Stockies are always a good option, I'm thinking of changing mine to stockies actually getting sick of feeling every bump.

 

[wraith]

What's the point of any modification to a car?

 

[SV666]

To what was said above I would also include extra weight to the vehicle as well, not by much but it would be more than what you started with. At this point in time I am deciding on whether if I should go to 20" rims just purely because that the stock 18's seem too small on the car (maybe its just me). Also debating whether I should just just lower it as is but I am yet to see a sv6 lowered with the standard wheels. Looking at pedders, either sports ryders or ssl's.

 

[RiCeY]

Nothing but disadvantages really, lower profile, less traction, reduce ride quality, more expensive tyres, etc, etc.

Stockies are always a good option, I'm thinking of changing mine to stockies actually getting sick of feeling every bump.

LOL

Advantages:

Improved handling presuming you retain the same rolling diameter. The reduced sidewall size gives a much stiffer tyre that improves cornering greatly.
More rubber on the road as they are generally wider so more traction.
Looks a lot better!

Disadvantages:

Harsher ride
More expensive tyres
Heavier, though the effect is debatable as Ive been down the 1/4 mile on both 19s and 17s and didnt notice any difference.

 

[TinSnips]

From what I understand, as far as grip is concerned, a 40 profile tyre is ideal for the commodore, ie. 19inch wheel. You won't have any dramas with a 45 or a 35 profile tyre (18 or 20 inch wheel respectively) but beyond that either way and you start messing with the handling (too much lateral flex or not enough) - and that is without going into legalities. As for the weight argument, it depends on what the wheel is made from and how it is constructed.

If you're purely talking about larger diameter wheels then it's basically cosmetic, but you can also go wider or have a greater offset which will impact on handling.

 

[nathanVY]

Definitely looks better, no doubt. As far as the wideness goes that's true but I find it just ends up spinning most of the time anyways lol. You will probably get better fuel economy on stockies, less friction.

 

[RiCeY]

Definitely looks better, no doubt. As far as the wideness goes that's true but I find it just ends up spinning most of the time anyways lol. You will probably get better fuel economy on stockies, less friction.

Tyre size isnt the only factor in traction, cheapo tyres will always give crap traction even if they are fat. The compound is also important.

As for increased friction with wider tyres it would be so minimal as to be barely noticeable if at all.

 

[nathanVY]

Tyre size isnt the only factor in traction, cheapo tyres will always give crap traction even if they are fat. The compound is also important.

As for increased friction with wider tyres it would be so minimal as to be barely noticeable if at all.

Very true, I have experienced this first hand. Steering will seem slightly heavier with the wider rims/tyres.

 

[VYMAD]

I don't see the point in these huge rims with jack-all rubber between them and the road.
My stepson hit a pot hole with these 20" rims or there-abouts, smashed two rims and sent him into the ditch. Rougher ride as well, with these bloody things. Nope I'll stick to my 225/50/16's.