Help me understand. What is the advantage to installing larger diamater wheels on a car other than looks/style? Is there an advantage? I can understand going to larger wheels to fit larger brakes, but other than that, cannot understand installing wheels larger than the car was designed for. To me most look very out of proportion.

tom...

 

lol very simple

larger wheel = bigger tire

bigger tire better handling, well in my case at least

 

I thought the smaller the tire sidewall the better the handling? If/when I get my C5, I'll probably be running the smallest possible wheel without looking stupid. Larger wheels just add on more weight, make your car accelerate slower, and makes everything think you're an idiot.

 

Good luck getting your C5. When will someone become a idiot, starting at 19"?

Paul G.

 

larger diameter wheels are mainly for looks.

larger width is to fit a wider tire obviously.

that being said, having a larger diameter wheel allows you to put on lower profile tires, while maintaining your stock ride height (granted you get a proportionate tire size to your match stock height; ie 275/40/18 stock to 275/30/19 modified). Lower profile tires have stiffer sidewalls which allow you to corner better.

Hope that makes sense.....

 

The larger diameter tire will give you a larger surface contact patch.
The larger diameter rims , if you will notice have smaller side walls i.e. smaller side walls result in less side to side movement, thus better handling.
Weight difference , well for the '01 Z06 Goodyear F1 made the tires 23lbs lighter than the Goodyears used on the coupes and 'verts. I can also assure you that the 16" rims / 50 series tire combo on my old '86 C4 were much heavier than my 18" 35 series FRC and 17" 40 series/"18" 35 series Z06 tire rim combo.
In most cases the lager diameter rim with smaller series tire wall offsets the small rim/ larger series wall tire combos in regards to overall height. So no loss in off the line performance as it affects gear ratios.
This is all generally speaking and only applies to a point. Most cars will benefit from going to a larger daimeter rim with a smaller side wall tire. Results are typical, but yours may vary.

 

I'm going to disagree in principle with most of what has been said here.

The fact is that the factors listed as reasons to "go large" can all be accomplished without a larger diameter wheel.

The contact patch improvement is far easier to get by changing the profile series of the tire. Widening the tire gives you more improvement in contact patch than making it taller. Changing the profile also gives you the sidewall size difference you are speaking of. I would caution that reducing the sidewall height of a tire isn't necessarily always better. If it were then you would see race tire with the sidewall no higher than the tread. There needs to be some flex in the sidewall to keep the tire from loosing grip ( I know its an extreme comparison but do you remember that is why radial tires were invented in the first place?). Weight is not a good reason for larger wheels. I believe when you do the comparison properly you will find that wheel for wheel and tire for tire, if you increase the size you will always increase the weight. The wheel material you add weighs more than the tire material you lose in all cases.

That all being said, if you want to change several of these items (sidewall, contact patch, tread width, overall diameter) all at the same time you will ahve no choice but to increase the wheel diameter. But, if you do, unless you also change to a different, and very expensive, wheel you will always lose the weight battle.

Of course, I could be wrong.

Larger diameter wheels are for looks only 99.998% of the time.

 

If and when I purchase larger wheels (18/19), it will be for looks only. All this talk of traction and contact patches seems like an excuse to me. You can get lower profile tires on smaller wheels too. I see a lot of guys auto-x with 17s all around. The only reason left to get low profile tires on large wheels is purely aesthetic.

Sure, larger tires will add weight and the larger diameter will rob a little performance...but its not like it will be "slow" afterwards. It's just an excuse to add more performance mods.

 

For me wider and sticker tires for traction on my FI setup

 

you clearly have no idea what you are talking about...at all.

I was going to rebute, but its not worth my time. Get informed.

 

Really? I guess I should go get some 20" dubs to hook with my power levels then.

TALLER wheels are bad for straigtline performance. Try getting a good tire for 19inch wheels in the back and running 10s or less in the 1/4mile.

The new c6 'vettes are fine with 19s in the back because they come with runflats, which are terrible for performance. 18 vs 19 really doesn't matter.

If you make any kind of power and you want to put it all to the ground for street racing or 1/4 racing at the track, 19 inch tall wheels and up will KILL your performance. No decent tires available. If you want to hook big power, you have to run 18s or 17s with Nittos, BFG DRs, or ET streets, in that order from worst to best traction.

As for cornering, any alleged increase in cornering ability in road racing applications will be erased by terrible straight line traction, unless you're making no more than stock power. And yes, most use 17 or 18" in road racing applications.

 

 

Some members including myself are interested in learning about C5/Z06 pros/cons of certain modifications as improvements...
Why can't you simply explain your vast knowledge w/o sarcasm and ridiculing the opinions of others?

 

Yes. I love the look of 19s or larger wheels, and being able to run them without hurting my performance would be a dream come true.

 

 

I did above...read the thread before being a big bad tough internet typer.

 

If someone can tell me how this is a 100% correct and accurate statement, I will stand corrected. Until then, I will stand by the fact that this is an ignorant statement. Any informed car enthusist would know this.

 

Low profile tires are about sidewall flex. The less flex, the better the handeling. BUT, on the street they offer a poor ride (generally) and make your wheels more prone to pothole calamities (like taking CHUNKS out of cast wheels).

 

Smaller wheels reduce weight and increase acceleration but limit brake options. In a drag race the smaller the wheel the better. Most Vette drag racers use a 16" rim as anything smaller wont clear the stock brakes. Road race guys need the bigger brakes so they need the bigger rims. Less sidewall flex due to a larger rim is good but not to the extreme. A 20" runflat wont flex for crap but wont get you around a track. You also have to consider the strength of the rim and how it will handle hard cornering. It's my understanding that most road race guys use a combo of 17s and 18s. Good enough to get you in and out of the corners and wont kill straight line acceleration.

 

IF you are interested in running runflat tires, putting 19 / 18 inch wheels allow you to run the C6 tires, an improvement.