I picked up some 18x8 rims and am going to attempt to put on some tires I have. The tires are 255/35R18 and 275/35R18. I know the 255s will fit but will he 275s? And if they fit, how dangerous is it to drive with them on? Thanks in advance.

 

putting a fatter tire on a wheel is not dangerous. your wheels are 8", 255mm= 10.03" and 275mm = 10.82.
youll be fine in regards to safetey, im not sure about fitment/clearance.

 

if anything the fatter tire is better / safer.

im not sure if the 275s will fit the rear if you are lowered

 

+1 for fatter = better. a fatter tire will give you a larger contact patch with the ground. a larger contact patch will improve braking distances/times and it will also translate into more power to the ground.

 

I read that if the tire is too big for the rim it will leak air and might come off while driving. I also read that it will make the sidewall "squishier" and this will decrease my handling around corners. Is this true?

 

the first part of the question could be true. sounds like it is but i have no data to reference and im not sure what the 'magical' number of mm is too much before leakage occurs.

as for too much sidewall translates into decreased handling in curves, this is 100% true. you will get more/faster feedback from a tire/wheel combo that is closer to itself in regards to width. that is one of the few benefits to people who 'stretch' their tires (in regards to the track, not the dudes who do it for looks)

for everyday driving, you dont have to worry about the decreased handling/response because you arent trying to shave seconds off your lap time at the track. in my opinion a larger contact patch is more important for everyday driving. plus, the larger tires will provide more comfort.

the only negative to a fatter tire could be decreased fuel mileage, because it takes more energy to spin those beefier (fatter) tires. more energy = more gas spent. i feel like the decrease will be negligible, though.

 

I'm running 235/35/19 on the front with a 19x8.5 wheel and 265/30/19 on the rear with a 19x9.5 wheel, and it's a somewhat beefy setup. I think those tires might bulge too much especially on the rear, the most dangerous thing could be the tire constantly rubbing and the tire getting "cut" by the fenders (I know this by experience).

When I first bought my current rims they came off a family members mustang and had 245/35/19 on the front and 275/35/19 tires on the rear (brand new Eagle F1's) and I had to change them after a month because the tire kept rubbing on my rear fender and the fender was actually cutting into the tire to the point where the steel braids were showing.

To prevent this I went with the size tires I have now and a little more camber to avoid cutting the tires. I would monitor the tires weekly on the rear and listen for rubbing just in case the same happens to you.

 

u will be okay as long as tires fit. but i think 275 is way too big for 18x8

 

don't mean to thread jack but since we're on the topic i've been meaning to ask a related question, i recently went from 225 to 245 40 on a 18x8 and noticed that the inside of the tire wears out quicker than when i was running 225, was wondering if this may have some correlation to running too wide of a tire since i noticed the tire has more of a "lip" and edge contact due to being wider and having more of a square shape.. just wondering if anyone can shed some light on this...

 

225= 8.85
245= 9.64
i wrote that down more for myself but anyways...
i think the reason youre experiencing wear on your tires is because as you turn your front wheels, they naturally develop negatiave camber. the 225mm tires were more this shape / \ (although exaggerated) while, like you stated, the 245s are more of a "square" so they have more to lose.

 

I think you answered your own question, kowala.

I agree with others who have said that a 275 is probably a bit too wide for an 8" wheel. Us Miata guys have found that the one of the fastest tire setups is a 225 on a 9" wide wheel. The mild stretch plays a role in how the tires perform. Some guys run 275 Hoosiers on the 9" wide wheels, and that's a very beefy setup. I can't imagine what it would be like on an 8" wide wheel.

As far as "Dangerous" is concerned - if it's not rubbing anything it won't be dangerous at all. It will just look funny and probably not drive very well.

 

makes sense, thanks for the quick reply!

 

long as the tire doesnt fold over lol