Im buying 20's and it says I can choose between either 20x7 or 20x8.5. Personally I perfer a wider tire but I was wondering if these would fit on a cobalt and if they would work with stock brakes.

Any help appericated.

 

Will they fit with stock brakes... sure, but I strongly recommend you upgrade them if you are adding that much extra weight. Plus keeping your stock brakes will make the wheel/tire/brake area look STUPID.

The tough part will finding be tires that are about 25" tall and come in 20" sizes.
I didn't search too long but you might end up using 225/30/20s they are 25.5" in tall. However in this size most tire companies are recommending a 7.5"- 9" wide rim.

A 8.5" wheel is getting pretty wide in a cobalt IMO. I'm not sure if they will interfer with anything or not.

 

What not get 29"

 

I guess I could just get the 7" and get a 225/35/20 tire

How much would a new set of brakes go for?

29 inch rims?

 

On stock suspension... you may be able to pull it off... could always run a small spacer.

I'm running a 18x8 w/ a 245/40/18 tire. fronts rub when Im on unevenpavement turning. but thats due to them being slammed low.

 

dont worry about brakes, ur car stops on a dime with half the brake down, there isnt that much more weight, its like having a full car and trying to stop

same here, but im not lowered and they still rub a lil with shitty michigan roads

 

good to know, and big brake kits are expensive as **** so thats not going to happen

 

its called unsprung weight. If you did back to back testing 70-0 mph from 15s to 20s I would put money that the 20s add another 15 feet at least.

 

and if u had the car packed with 4 200lb people vs 1 200lb person, i bet it would add 15 feet

 

Your buying 20" wheels and tires......the tires along can cost between $600 and $1200.
you will have a 1/4 of the cars value into wheels and tires. And you going to say a upgrade brake system is too expensive?

Whats your point?????

True of False
A Cobalt in stock fom will stop slower than a cobalt with 20inch wheels, twelve 200lb people, that is pulling a trailer

 

i said 4 200lb people

 

The rims are 1250 and tires 550, not really half the value but I get your point.

 

But, what if you had 20" wheels AND you have 4 200lb people in your car? Your logic is flawed.

On a side note, 20" wheels and 4 200lb people... sounds like a drive-by shooting it about to go happen!

 

Jesus christ this thread is hilarious If you're going to buy 20's just make sure you get them as light as possible, some 20's can weigh just as much as a regular 17 if you don't go getting a fat ass plate rim. You can fit upto I believe 235/35-20's on the car but depending on a drop you might need a spacer like someone already said. 8.5's are not a good idea with the 20's man, sorry. Why not just buy some really nice 18's and throw some 245/40-18's on there, would be more of a contact patch, lighter unsprung, better handling, stopping (depending on the weight of the rim). I think 18's look awesome on the cobalt, just drop it a little to match it. Plus with the fatter sidewall your car might not ride like ****

 

hahahahahahaha!!!!!!

and for my own side note, how does 4 200lbs people effect the looks of stock brakes compared to big brakes thru the 20" wheels anyways?

and one more thing.......y the hell would you out 20's on a cobalt? its a freakin sports car. oh well to all his own. good luck

 

I run 18x8.5 inch look in my gallery theres some pics of them

 

When you are refering to acceleration or deceleration, you are really refering to the rotational inertia of the wheel. Sprung/unsprung weight and its ratio would apply to the action of the suspesnion movement.

For the 5% of the people who actually care about performance. There is a REASON why in most "time based" motorsport (which excludes drifting) and within the dictated rules, race cars will always use the smallest wheel that they can fit, the widest they can find and the lightest they can afford; and it all had to do with basic high school physics but I am not going to go into all that.

If people are interested, either they already knew about this or now is about time to start looking it up.

 

I wouldn't go any bigger than 19's. 20's make the car sit too high, even when lowered. They just look too big for a compact car.

 

^^Smart Guy^^ Thank the gods someone understands! Extra rotational mass will subtract from your acceleration and breaking, and the extra diameter will totally throw off your gearing especially if you're rockin' an LS or LT which come with smaller tire diameters to begin with, SS's you can get away with because they come with MUUUUCH larger diameter tires from the factory. My 17's even throw off my gearing.

 

idk 18's on a cobalt just look small to me.

and on tire sizing what does the first number mean 225/230/235 etc?

I always thought it was the tire width. when ordering tires online how do I know what width im getting.

sorry for the dumb questions

 

100% correct
circle forces ie torque comes to mind. physics noobs probably don't know what the acceleration due to gravity is.

 

That is the width in millimeters. The second # is the sidewall as a percentage of the width.

 

Not a dumb question.

Read eveything in this tech guide and prepare to be power leveled -> http://www.tirerack.com/tires/tiretech/tiretech.jsp

 

Raise dat bitch up and put some 24's on it..... WOOT WOOT