Great wheel and tire combo Andy! Looking forward to seeing this. :tup:
Z1 and Z2 are competition tires.
Federals run about 10mm wider for the sweet drift kids to stretch them for competition. 225 fits for a 9" wheel.usually thats an 8" wheel size
Someone correct me if I am wrong, but I guess the 265 should be faster than the 275 anyway because it is spreading out the contact patch more for that 9.5" rim
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I was told by another guy you want to have a slightly wider tire than wheel so the shoulder can come out past the wheel instead of the “stretch” where it’s pulled back from the rim. I guess the mechanics of it make sense.
Maybe if you plan on hitting curbs while driving or trying to park :lol: i would think that would make the sidewall a little loosey goosey
You want to run the correct tire section width to the correct rim width range as recommended by the tire manufacturer.
When running outside of his range there is poor contact patch, decreased cornering grip, and increased tire wear (both stretching and over sizing will have negative effects on how the normal load is transmitted through the sidewall and thus the shape of the footprint) . Typically the optimal rim width is at neither extreme of the given range.
For a 275/35R18 both Toyo and Dunlop give a rim range of 9-11", but I wouldn’t be surprised if the optimal rim width was the same as “Measuring Rim Width”.
The wheels I mentioned are 9.5’s. What do you do when some manufacturers “run” a little wider or narrower than what might normally be recommended for a wheel?
it shouldn’t be a problem for the wheel, as it will still be within the range for that wheel, but will become a problem as far as rubbing while turning, or if you’re really low and stuff like that.
the maximum wide tire i can run on my wheel that will fit without having rubbing issues is a 255 in the rear. if i were to buy that tire i would have problems if it ran big. usually they dont. most have a slight variation but not significant enough to usually matter.
you can compare the tires section width/tread width and various other specs. also be aware of the tread depth. the dunlop ZII are 9/32 new, the nittos are 6/32 new. so although the price may be lower, are you actually saving money?
Running 285 in the rear and 255 up front, no rubbing, so I think 275 would be a fair compromise. I could raise the coilovers a bit as well if needed.
Without doing a comparison test there is no definitive answer. Lower molded tread depth will usually wear better in harsh conditions. In this case we are also comparing different compounds.
I agree with a separate tire / wheel combo for these types of events. I plan on doing the same eventually, but I’m in no rush. I’ve already smoked you (1QIKZ) at the drag strip 
Are you still running into the john with your iphone, replaying the vid, and beating off? You wanna rematch my friend, you just let me know.
Have you considered running 17’s?
Not with the brake rotor upgrade. 18’s just make it. I also don’t want to start mixing up tire combinations, just in case.
Also found this stumbling around the net. Not sure if it’s helpful to anyone but at least it seems to be able to put all the magic numbers in some sort of visual format. Let me know if you think it was in any way helpful.
Another thing you might want to consider is some brake ducting, and not sure if 300Zs are prone to cooling issues? I know when I tracked my supra the brakes faded out completely when running at the Glen without ducting. If your just messing around at TMP with short sessions I wouldnt worry about that as much. If you have never been out to a track day I would get in a few events a TMP and see if you like it & see how your car reacts.
Yeah, I’m gonna have to run a couple events just to see what type of results I get. Z’s came with factory air deflectors mounted to the tension rods. Not sure how effective they actually are.
The stock air deflectors help a bunch, but most cars don’t have them anymore after years of ownership. Brake ducts are fairly easy to install too. I can’t remember if you still have fog lights or not?
I do, but I have considered deleting them more than once. Just need to wait for you to park for more than 5 minutes.
I’ve been REALLY impressed with the Z1 star spec in an autocross setting, very easy to drive. They wore terrifically well, they were on a 2000lb civic, but they were being abused by multiple drivers for most events. From the early reports I’ve been seeing the Z2 is just as good. I would also heavily consider the hankook rs3, they deal with big cars better than some of the other 140-200tw tires.
If you’re going to be autocrossing, keep the treadwear over 140 for the novice class. I’ve picked up that a very very mild stretch is faster in an autox setting with street tires, for example, a 195 on a 7.5" wheel is the current fast setup for civics in a specific class, even though they’re allowed a 225 on a 7.5. I wouldn’t worry about finding the widest tire you can, I bet that car will do great on a 245 or 255.
I’m not completely settled on rubber and will have to sit down and compare all the factors associated with each. As far as usage goes, I’d like to do as many SCCA events as I can and at least one to two tr ack days depending on my time availability.