SocalC5Z

I’ve been running a square tire and wheel setup on my C5Z for a few years and now that my last set of Nitto 555RII are done, I need to get new tires. I’ve been running 285/35-18’s on factory 10.5 X18” square and looking at the Nitto website, discovered that the appropriate options for the NT01 are either 305/35-18 or 315/30-18

I did some research here but it seems guys are using both sizes. My car is stock ride height with a track alignment and T1 bars. I do not want any rubbing on the fenders. Anyone have any feedback on the NT01 square on a C5

Dan H.

Search my profile (threads I started), I actually ordered both tire sizes after realizing people had issues with the 305/35's fitting. Are people using them yes, do some have to raise the ride height to be able to use them, yes. Realizing this after my order, I picked up a set of 315/30's and went with those instead. I had no issues putting on the 315/30's other than DRM brake duct rubbing which will happen with any tire.

Miguel S

Did the same based off of Dan's advice. I have steering rack limiters to avoid chewing up the brake ducts and I'm lowered about an inch in the front and 1/2" rake between the jacking pads.

Quickshift_C5

These are the same tires I'm looking at as well with a square setup. I'd like to avoid tearing up the ducts. Can anyone expand on the steering rack limiters or provide a link to what exactly was done?

Why do the 315s fit better than the 305s? I assume the 305s were slightly taller due to the profile?

Soloontario

Definitely use the 315s. They are sig shorter which really helps.

SocalC5Z

This is great info...thank you Dan H and everyone else. With the 285's my DRM front brake ducts are already rubbing, so I'm used to not using full lock. My big concern was fender rubbing which some folks don't seem concerned about but is unacceptable to me.

As for steering locks, on my last race car I used two piece machinists clamps which are designed to clamp bar stock. Worked fine clamped to the steering rack to provide steering stops.

STANG KILLA SS

thats a great idea. i may do that.

im also running 315/30/18s. havent tracked them yet though. still preping.

Dan H.

https://www.corvetteforum.com/forums...t-tire-c5.html

Pics are in here 305/35 vs 315/30

Quickshift_C5

I agree, great discussion and good points.

I was considering using split lock collar, and adding thin rubber bushings on the side it will hit. Has anyone done this?

Does anyone have a photo of the stops they've installed?

Miguel S

[QUOTE=Quickshift_C5;1594103017]These are the same tires I'm looking at as well with a square setup. I'd like to avoid tearing up the ducts. Can anyone expand on the steering rack limiters or provide a link to what exactly was done?

I bought rack limiters for a 79-04 mustang. It was a 6 pack for about 20 bucks. They are plastic and clip on the rack under the boot.

I also put gorilla tape on the duct where the tire would hit and replace that as it wears as opposed to the plastic duct.

Quickshift_C5

Just looked at the Mustang rack limiters, not a bad idea! Simple and effective.


So, another question. For those of you that say you were rubbing the edge of the fender with the tires, I assume that's only under compression on big bumps are hard turns at the track. When sitting at rest, do you know the measurement of how much gap there was from the tire to the fender? In other words, how low did you have the car?

crimlwC6

I've raced on NT01's both 275 and 315 x 17 sq set ups for a few years. Excellent tire that was about 1 to 1.5 seconds slower than Hohos on tracks with fastest times 1:00 min to 1:08 min. I usually started at 28 psi and lowered hot pressures through out the day to 33 to 35 psi. Extremely predictable tire that takes tons of abuse. 315s wear longer and run faster than 275s (big surprise!

Quickshift_C5

Slower than which Tire? Did you mean the Toyos? Because, in every single thread I've seen and researched on the topic, virtually ever....that has not been the case.

Miguel S

I believe he meant Hoosiers, but I don't know if they were R6/7 or A6/7. In other threads, brkntrxn has posted time difference between NT01, Hoosier R, and Hoosier A.

stevensa

I would look into the Maxxis RC1 in 275/35/18. They run identical lap times to NT01 but wear wayyyyyy slower in my experience. I used to run a lot of NT01 as practice tires and liked them a lot, but there is no doubt that the Maxxis is better (based on my personal experience).

aaronc7

Where do you get them from?

Quickshift_C5

I saw a video recently saying that the popular 18x10.5 using 315 tires ruins steering feel and it's harder to tell what the car is doing. First I've heard of this. Is there any truth to it?




I would much rather drive to the track on an NT01 than the RC1. It's quite literally a slick with 2 grooves.

stevensa

True when new, but keep in mind that the NT01 go down to 2 grooves as well after half of the tread depth is worn off.


I bought them direct from Maxxis as that was the only source back in Jan 15. I stock piled a bunch from their contingency program though and honestly haven't shopped around since then.

crimlwC6

Correct. Just finished a race on new 315s on 17x11 rims. I'll be getting more. The guy in front of me is on the same tire. Track was wet and oil was all over turn going onto the straight. I didn't adjust the pressures after running in the rain so they got a bit wild halfway into the race. You can over drive them, lock them up and they don't care.

Quickshift_C5

Getting ready to pull the trigger on ordering this setup. Ordering wheels and 315 wide NT01's.

Is there any reason I "shouldn't" do this? Any negatives beyond rubbing?

Any comments about the poor steering feel and feedback I mentioned above?