[bmslutie]

I am wondering what is the tallest front tire size you guys have run on a stock ride height 350Z? I wonder because I have been running a 255/40/r18 on the front and on one side it sort of ate up my fender liner. I assumed this happened on track when the suspension was completely compressed and the wheel was turned a lot. It may also have happened at autoX.

It may have been that my fender liner was not properly postioned. I repositioned it now.

I want to run PS4S but they do not come in the 255/40r18 and 275/40r18 I have been running for years. Its the 275/40r18 I cannot get in the Michelin. So one option is running a 265/40r18 and 285/40r18 which will raise the entire car 0.3" but comes with the caveat of that tall front tire. I want to know if it will fit.

Why such high ratios? Chicago. Our roads are garbage and we have these giant speed humps on every side street that I can barely get over without scraping as it is. That extra 0.3" would be amazing as far as tooting around the city is concered.

For the track a 275/35r18 and 285/40r18 would be optimal but that would make it even harder to get around as that drops the front by 0.4"

Other options is to run a 255/40r18 front with either a 265/40r18 rear or 285/40r18 rear. The former I do not like due to pure aesthestics but the driving characteristics would probably be more nuetral. The latter would look better (some nice meat in the rear) but thats a serious stagger and may change the handling of the car and I will have to retune.

Any real world info on any of these setups will be a great help to me. Thanks all

 

[dkmura]

Welcome and what size tire you use on the front also affects the rear, as the wheel speed sensors will detect rotational speeds of each end. As a rule, the fronts can be slightly shorter (with 5% of overall diameter) or equal size, to prevent VDC from kicking in. As for the front fender liners, I've found that most sizes beyond a 245/40-18 will cause damage with track driving. My SCCA Z33 has raced in different classes and used everything from 285-30-18 to the 245s. The wheel liners get shredded over time, so that's why I recommend either 245-40-18 or 245-35-18s for street/track use.

 

[bmslutie]

Welcome and what size tire you use on the front also affects the rear, as the wheel speed sensors will detect rotational speeds of each end. As a rule, the fronts can be slightly shorter (with 5% of overall diameter) or equal size, to prevent VDC from kicking in. As for the front fender liners, I've found that most sizes beyond a 245/40-18 will cause damage with track driving. My SCCA Z33 has raced in different classes and used everything from 285-30-18 to the 245s. The wheel liners get shredded over time, so that's why I recommend either 245-40-18 or 245-35-18s for street/track use.

Thanks for the info. My car is a modified base model so I have no VDC. I did not want to deal with that which is why I purposely bought a base model and upgraded the diff to an OS Giken and slapped on the track brakes.

Maybe I will just deal with replacing fender liners as it goes. I really do not want to narrow the front contact patch.

Maybe I should just kill my PS4S dreams and go with something with a stiffer sidewall like the Yoko V601 or just say screw ride comfort and slap on some Goodyear Eagle SC3. I imagine the SC3 are incredible on the track and probably very annoying on rough roads.

 

[dkmura]

My preorder '03 track model runs 245-40-18 fronts with 275-40-18 BFGoodrich G-Force A/S tires. They clear the fender liners in front quite easily, but with some suspension changes handles near neutral. The fender liners are important to preserve, as they protect important brake and electrical lines.