my friend is in the market for tires for his axis milano rims. i used a tire calculator and it calculated that mathematically the 275 35 19s are the ideal tire for 19 inch rims. his rear rims are 9.5 inches wide. however the shop that he ordered from said that the 35 series tires would be dangerous if mounted on those rims, and that he should stick with 30 series tires for the rears.

is this true? if it is, could someone please explain to my why it is? the 30 series tires would throw off his speedometer by about 3 mph at 60 mph.

maybe i am just a bit ignorant, but it doesnt make sense to me. would a 5% difference in sidewall height make that much a difference in safety?

thanks for any help.

Gary

 

i don't know, but that's what i have.

 

i think most people are running 275/35/19's out back. From what I've read on here the 275/30's are more of a "tuner" size.

Then again I went with 285/30's out back but just because they were around $60 cheaper each then the 275/35's. I have no idea why they were that much cheaper though.

 

What kind of shop told him this?!?!?!

The correct sizes would be
245-35-19 front'
&
275 or 285-35-19 rear.

 

thanks, that is what i thought. the shop is called rdm wheels. http://www.rdmwheels.com

that is what i told him to get. 245 35 19s and 275 35 19s. they are refusing to put on the 35's in the rear due to "liability" issues.

edit: well, i just spoke to my friend and he said that he already ordered it and it should already be on its way. oh, well. i tried.

thanks for the input everyone.

 

That statment by that guy confuses me. By going with 30 series your sidewall height drops .6". You would think he would want you to go with the 35 or the 30.

 

liability issues? wtf? so he wants you to put on the wrong size.. and refuses to install the correct 275/35s???? wtf?

 

my friend said that the guy at the shop insisted that they install 275 30 19s on all the z's. it is some sort of package deal apparently. 245 35 19 fronts and 275 30 19 rears. maybe that is why they were coming up with the bs about not being able to change the package? i dont know. sad to say, but my friend is too gullible when it comes to things like that.

believe it or not, this is going to be his 2nd set of rims and 3rd set of tires in 3 months. anyways, i scored a nearly brand new set of 245 40 18 and 275 40 18 nittos out of this. his stubborness is my gain. i would feel sorry for him if he didnt always go against what i recommended to him.

 

Howzit ragtopz, after researching tires for awhile, everyone seems to favor the 275/35's

I got them on now and seems to be not to big of a deal.

 

I think it's because the wheel shop mostlikely got some huge deal on the wholesale price on those 30 series tires, that is why they insisted promoting those 30 series tires like hell!! I've never seem any shop refuse to put the correct tire size on due to liability issue? That is bunch of BS!!!!

 

heh they wanna see liability? if he ever gets into an accident he could say the VDC came on improperly due to incorrect front to rear ratio of widths.

of course its probably not gonna cause an accident. but it will kick in when its not needed. he just made the ECU think the back wheels are spinning an inch or 2 for every revolution..

that tire shop has idiots working for it, and I would consider them bad business. liability issues... yeah, there are, like running shorter sidewalls so they can sell more rims when you bend one.

 

just an update on this situation. i made a mistake, my friend ordered the rims from spy engineering.

anyways, he called them last week because it had been a while since he had placed his order, and they still had not shipped it out. he asked them to change the rear tires to 35s and they finally agreed. my friend was a bit irritated that it wasnt shipped out yet, so they agreed to fedex them out.

so anyways, on wednesday he received his left rear and right front tire only. i told him jokingly that he should just mount those for now. he was not amused. don't know exactly what is going on with that company. hopefully, for the sake of my friend's sanity, the other two rims will arrive some day soon.

 

I dont think this is accurate. I have 245/35/19 fronts and 275/35/19 rears, and my rear tire is NOTICABLY taller than the front. I should have gone with the 30. Aspect ration is a ratio of height to width, do my definition, a 35 series tires are not all the same height....it is a function of the width. Please explain.

 

245/35/19 front and 275/35/19 is correct. The "Z" and "G" coupe have a designed in stagger. Give or take, the fronts are 25.7" in outer diameter and the rears are 26.7" in OD. This is exactly the same as the stock 18"s which are 225/45/18 front and 245/45/18 in back. Notice 45s on both ends and different cross sections front and rear?

And yes Mr. gq_model, your back tire is taller than the front, 1" taller, as explained above. This is as it should be. If this were not the case, VDC and the slip light would be coming on, and the handling would not be anywhere near as good as you are now enjoying. What DiscountTireDirect said is correct.

Lou

 

OK, this is starting to make some sense. However, why would you NOT what the front and back tires equal in diameter (aside from the VDC slip issue)? I assume that in stock trim, having the front lower than the back increases handling in some way? I just don't like how my car looks like a muscle car, with thick sidewalls in the back, and a noticablly taller tire. Just looks funny IMO.

 

Our cars were designed to handle by the engineers with a staggered setup. It's not that uncommon. The Vette is designed that way as is the new Ford super car. Most of Italian Exotics are designed this way also. I really can't explain why, maybe it's for that nose down look. Anyway, it seems to work. My "G" handles wonderfully with the 245/275 staggered setup. I wouldn't change a thing.

Lou

 

I just got the Axis Milanos and was also advised to do
275-35-19's in the rear and 245-30-19's in the front...
I've also seen them advertised the same way.
I didn't see a visual difference so I just went with it.


https://my350z.com/forum/attachment....&postid=714004

 

I still think it's a bit strange. If you look at most supercar tire setups, such as the Porsche, Lambo, Ferrari's, they have have a smaller aspect ratio in the rear. I would assume this is done to keep the overall diamter of the tire/wheel constant front and back. Do they know something the Nissan engineer's don't?

 

smaller ratio, but many of them are running tires like 245 in front and 335 or higher in back. even with the smaller ratio, its larger overall.

I THINK the reason is that the front do the turning, thus you want small sidewall and no give. a nice tight handling feel.

in the backs you want the sidewalls to give a little, gives you a little more notice before the backs break loose, and for launches, a sidewall absorbs surges in power rather than just spinning.

I beleive overall the clearance in the front is the same as the back, by that I mean the frame is level to the ground. the just sit the car a little lower on the suspension in the back to compensate for larger tires.

 

dwizzay, I hope you mad a mistake and meant 245/35/19s in front. 245/30s would definitely be too small.

Also, gq, if the added rubber bothers you, you could run 19s in front and 20s in back. 245/35/19 and 285/30/20. Just a thought, if it really bothers you. In other words do the stagger with the wheels rather than the sidewall rubber.

Lou