I noticed that the rims that I was gonna buy was 18x7.0. Is it bad? Cuz most rims were 18x7.5. Which is better or it really doesn't matter?
what tire size should I get with 18x7.0? 225/40/18 just like 18x7.5?
I was thinking about getting Nitto NT555 or Toyos Proxes 4 or Yokohama Parada Spec-2, but what if the size is not available?
Please tell me if I need other size than 225/40/18 and what tires have that size (Nittos, Toyos, Yokohamas, etc)

Also, anyone knows where I can get these rims? or anybody has good hook ups?
Motegi FF7 Gunmetal 18" for good price and with tire package.

 

18x7 is fine. Go with 225/45/18 if you want to match stock diameter.

Just make sure the offset is +45 or higher (+42 will work but you gotta do more research)

 

I would definitley look for a wider rim, atleast 18x7.5. The wider the better IMO. As long as it doesn't rub ofcourse. 18x7.5 +45 or 18x8 +50

 

Thank you guys! I'm thinking about 18x7.0 with 225/40 or 45/18 tires. But why 18x7.5 rims are better than 18x7.0? looks better? comfort?

 

Looks better, wider stance, you can fit wider wheels, more traction etc.......

 

The same size tire on a wider rum will have a slightly wider footprint.

But it's such a minor difference I wouldn't worry about it unless you REALLY want 235/40/18 tires.

If the rims you love are 18x7 then that overrides any minor (probably negligible) improvement in handling.

 

It's for safety reason. Most tire manufacturers that I have checked recommend a minimum wheel width of 7" wide for their 225/45/18 tires and 7.5" for their 225/40/18 tires.

Wider tires need wider wheels, and lower profile tires also need wider wheels. When tires are mounted on wheels with insufficient width, the sidewalls are constantly at stress even at standstill. These tires will function ok when new. But given enough time, the sealing bead and inner belts will become fatigue due to the unnecessary stress, and may eventually break apart. Worst case scenario - tires coming off the wheels during a spirited high speed sweeping curve or during an emergency maneuver trying to avoid someone running traffic lights.

Always follow manufacturers' recommendations. Who would understand tires better than the manufacturers that design and build the tires themselves. A classic example is the "Ford Explorer - Firestone tires" case. Ford dis-regarded Firestone's minimum recommended inflation pressure, and deflated the Firestone tires to compensate for the SUV's high speed lane-change instability. Results : death and lengthy, costly lawsuits.

I hate whenever I heard people said they were using tires mounted on under-width wheels and they worked fine. Sure, the tires mounted fine and performed fine when new. But can never be so sure many months and many thousand miles down the road. That's why some responsible tire and wheel shops won't install tires on under-width wheels. These shops care for customer's safety, not their money.

It's ok for those who know the risks of using under-width wheels and are willing to compromise their (and their passengers') safety by continue to do so. What I afraid the most are those newbie's who are looking for advices, follow these ill-advices without realizing the potentially deadly risks involved.

 

Has Edward scared you enough yet? LOL.

I would only say this. Tire manufacturers are EXTRA CONSERVATIVE because they want to avoid lawsuits and liability. If you go out of spec, it's YOUR risk but I think that calling it deadly dangerous is grossly innacurate.

I have never heard or read of a story of any of the hypothetical "tires coming off" scenarios happening. Not one (and Ford Explorer nonsense doesn't count in my book).

235/45/17 on a 7 inch rim is only slightly out of spec and plenty of people have done it. There are performance tradeoffs but I don't believe there are safety ones.

If you trust manufacturers blindly then you would never use anything but Acura brake pads and rotors on your car. When I took my Type S to the dealer in the winter it was mounted on 16 inch TL wheels and the service lady told me that it was dangerous because those weren't designed for the type S. All I can say to that is ROFLMAO.

 

Hemants, one quick question. Why do "tire manufactcturers are EXTRA CONSERVATIVE because they want to avoid lawsuits and liability" ? Because they know there is a potential that the tires might fail when mounted on out-of-spec wheels, otherwise why do they ever need to worry about lawsuits and liability ? When they have to think about lawsuits and liability, it obvious that there is something they know but we the consumers don't.

I repeat again. I know plenty of people have mounted tires on under-width wheels. These tires will not all fail at once. But with age, there is a possibility that some of them might failed under more stressful situations. Just like our stupid tranny. Some failed but most don't. It's ok for those who know the risks and are willing to compromise their safety. But please don't tell everyone that there is no safety tradeoff by mounting tires on under-width wheels.

I don't quite understand your logic on Acura brake pads and rotors. But what I understand is that if, say Rotora recommends using rotor X and pad Y on an TL-S, you won't go and install them on a NSX. Aftermarket parts manufacturers almost always build parts that exceed the OEM specs, otherwise who would go and buy them.

 

"I know plenty of people have mounted tires on under-width wheels. These tires will not all fail at once. But with age, there is a possibility that some of them might failed under more stressful situations"

Has this happened to even one of these "plenty of people"?

"I don't quite understand your logic on Acura brake pads and rotors."

Simple. An Acura service tech might say "don't use anything but genuine Acura parts in your car". Would you take that at face value?

The best analogy is Comptech headers. If Acura could have safely produced more HP out of the Type S engine, wouldn't they have done so? Maybe Comptech headers are going to make your engine overheat and blow up?

Yes, it is your risk because you are taking matters into your own hands. But it is not blind risk, it is calculated risk and IMO very reasonable.

Long before the tire comes flying off you will see uneven wear or signs of heat buildup on the shoulders which have to flex a bit more to allow the sidewall to meet the rim. ie. the expected result would be loss of tire life not danger. But most Z rated tires are more than equipped to handle this as they are designed to dissipate heat effectively.

 

Why do manufacturers have safety recalls even when there is no reported problems or injuries ? Because they detected the affected parts had a potential to fail, and luckily none had failed yet. I sincerely hoped that nothing will ever happen to those "plenty of people", but it doen't mean none of these stress-out tires will not fail given enough time down the road.

When an Acura service tech say "don't use anything but genuine Acura parts in your car". He is partly correct, because cheap belts will break, cheap gasket will leak, cheap oil filter will clog. It's a jungle out there. Who knows what the corner store garage will use just to squeeze some profits out of you. I once overheard a service guy told this to a customer. "The aftermarket brake pads you installed were too hard for the stock OEM rotors, and had cut deep grooves making the rotors completely useless." The customer would be ok if he installed both aftermarket pads and rotors. Acura doesn't warranty aftermarket parts because it has no control over their specs and quality.

Same with the tire issues. The only thing that tire manufacturers have control is to recommend the wheel width range on which their tires can SAFELY be mounted and tested ok.

For the Comptech header example. Honda/Acura is a big coporation listed on the stock market. It has many vehicle lines and has long-term marketing strategies such as with model features and model horsepowers, etc. One cannot just say let's give the TL-S 30 more horsepowers without completely screwing up the carefully laid out business plan, even though Honda can tune 30 more hp with ease. Adding another 30 more hp may involve adding strengthening supports to the chassis, larger clutch packs for the tranny, larger brakes, wider wheels and tires, revised suspension, RWD conversion, etc., again for SAFETY reasons. All these SAFETY improvements together with the 30 more hp will eventually bump up the price of the car. Not the mention that this new TL-S will step into the new RL's territory (300 hp) and screw up the new RL vehicle line.

If Comptech builds its headers for the TL-S and offers full limited warranty for its TL-S headers, this product is unlikely to fail. However, whether the additional hp will hurry the weak tranny to its demise is not Comptech's concern. It's Acura's concern because Acura is to pocket all the tranny replacement cost.

Back to the tire discussion. When tires are mounted on under-sized wheels, the tires' sidewalls are under great stress. The two tire faces are being forced together by the much narrower wheels. Under this condition, the tire's sidewalls are trying to spring out, whereas the wheels are holding the tire bead to stay put. This tension is unnecesary if given wheels of recommended width.

So the tire bead is under stress, the inner belts on the sidewalls are under stress. Heat is not a problem here, its stress. Given time, rubber will age and metal will fatigue. When metal become fatigue, it just break without warning. If these tires don't come off the wheels, they will sure blow out and fail.

 

All your speculation my friend. I guess we'll have to agree to disagree. Here's where we disagree in particular:

"The only thing that tire manufacturers have control is to recommend the wheel width range on which their tires can SAFELY be mounted and tested"

Recommended wheel width range is the range in which you be able to get optimal performance from the tire. Outside this range something is compromised but that compromise is not necessarily safety.

You talk about sidewall stress, I'll tell you what gives a side wall stress...being a sidewall and getting bashed around on roads!!!

Tires are made of rubber and they are designed to flex.

Let's examine what Acura put stock on the TL Type S. A tire with a section width of 215mm. That is about 8.5 inches. The wheel width is 6.5 inches. The sidewall is ALREADY FLEXING in order to be mounted on the wheel. If you put on a 235mm section width tire, it has to flex an extra 10mm or 0.39 inches on each sidewall. So you think that magically this sidewall which is getting bashed over every bump and perfectly safe is all of a sudden going to come flying off because of this extra flex?

The proof is in the pudding I suppose. Whether in person or on the entire internet, I have never heard of such a thing happening. Could it happen? Of course. But you characterize it as though it is likely to happen which i categorically disagree with because it defies logic. Before you saw sidewalls come flying off the wheel you would probably see an increase in bubbles. Have you even observed this? I haven't.

Recommended range is where the tire will perform optimally. You interpret it as where it will operate safely. To me that is not the same thing.

 

ok I have a question then. I have an 03 TL-s which has a 215/50-17 stock tire. Im going to upgrade the rim to 18x7.5 with a 45 offset the 225/40-18 are only 1.5% off in size. but if you compare it to the tl-p tire size of 205/60-16 it is 2.3% off. which is over the 2% deviation guideline. does Acura recalibrate the type-s for the new wheel size? or should I be basing these calculations on the tl-p stock rolling diameter?

 

The speedo cannot be recalibrated to compensate for the different rolling diameter of your new setup. You should also compare rolling diamter to the stock tl-s wheels and not the tl-p setup. 225/40-18 should be just fine.