Hi, This is my first post here. I have a G35c 5AT w/ 17 inch wheels the tires on their now are a 50 series tire. The stock 18 inch are on a 45 series tire. So how come everyone getting 19's with a 35 series tire? I really want 19's but would prefer something like 275/40/19 because chicago is full of potholes.

thanks

 

you are adding another inch of rim past the 18" size; and as such to keep the same outer rolling diameter; you must remove .5" from the sidewall(.5" radius; 1" diameter, to compensate for the extre inch of rim)

if you just get 19" rims and the same amount of sidewall as a 18" rim; your overall diameter is now just 1" larger; which is enough to affect your gearing; and not in a good way.

also you may ask; 17" gets a 235/50; 18" gets 245/45 so logically a 19" gets 245/40; and on those lines youd be correct; but a 275/40 is not the same as a 245/40; infact a 275/35 and a 245/40 is less than 2mm difference. series is a percentage; so as you go wider; you must take that into account.

if you need X amount of sidewall; you need to choose your rim size accordingly. thats the risks you take if you choose a larger rim.

 

if you stick with the same widths then going with a 40 series is probably since the overall diameter is still the same.

but typically when people upgrade wheels, they get wider widths as well, thus needed a wider tire. with a wider tire, you need less sidewall to keep the overall diamater within spec.

 

I just answered your question over at freshalloy. Take a look.

Sorry, Mike, but your answer is wrong. As you go wider withen a given aspect ratio, the sidewall gets bigger, so to maintain, the same sidewall height, you lower the aspect ratio.

Lou

 

exactly...its done to maintain stock, or as close to stock overall rolling diameter.

 

If you want to go 40 series, you will need to lower the car for the right look, but you can go with 245/40 front and 255/40 rear. I'm out of town, so can't post a pic, but if you go to www.g35frenzy.com and look at the 'Show us your G's' thread, you can see a pic of my black g35 with eibachs and the above tires. If you don't lower, it looks too tall with those tires. You can also see Chops car there, he has the 245/275 35 series combo with eibachs.

 

MAN I HATE THIS!

I don't want to lower, I have a lowered Accord but I think the G is the perfect height for my Area. You guys in nice climates are lucky I just really want 19's All I have are stock 17's and I know I am getting new rims and tires for summer time. Seems like the stock 18s are my best choice because of the 45 series tire and price. I really don't want to spend alot of money on forged rims to take a chicago beating. Whats the worst that would happen if I got something like 275/40/19? I can deal with the speedo being off but don't want to lose VDC or other major things

 

OK what about 245/40/19 and 255/40/19 ? Will that work?