Hunh? “Used to be?” What’s recommended now? Not sure what’s changed in the last 50-some years.

 

I posted it....8.5" you can Google images and it will show you stretched tire at those sizes, but it does depend on manufacturer I suppose.
For my 18x8 the 235 Contis do not look square while the Yokos or Michelins will.

 

So, I'm out of date I guess. The recommendation now is to run a 245/40-18 on an 8.5 instead of 9 or 9.5 (which is totally acceptable... even OE is 245/45-18 on 8.5)? OK, I get that.

Let me clarify my thoughts (right or wrong): When I worked for Datsun (40 years ago), we had a guy from Goodyear Racing come in and explain how to size a performance/racing tire and he was the first one to introduce me to the "1.2 Rule" (or 120% Rule if you prefer). And that for a racing tire (or performance application), one shouldn't go below 90% tread to wheel width NOR exceed 120%. This doesn't mean a tire smaller than 90% or larger than 120% of the wheel can't be fit to a given wheel size as a lot of passenger and truck tires go well beyond the 120% upper limit. But, performance starts to drop off above and below that due to any assortment of factors, mostly related to sidewall flex/rollover.

So, again, no one is wrong here. But I will go back to the availability issue. 18s seem to be going the way of the dinosaurs for some odd reason. Unless you go with something with a lower aspect ratio, e.g. 285/35-18. But then, the diameter goes all out of whack to stock diameter tires leading to some minor issues like speedo error. But also some semi-major issues like speed sensors going crazy and telling the ECM to "start that VDC thing right now"! Laff...

And just to show you I'm just splitting hairs here, note that I have both 255/40 and 285/40 alternates in my Z tire sizing spreadsheet. I tend to trust empirical data.

 

Damn newb, whippersnappers I swear. Back when I first bought my 350z in 2005, 245s on x9.5 was the standard "go-to" size recommended by nearly all vendors and members here for the 350z even though people were still stumbling through to figure out the best recipe with offsets. As you can see from the previous comments, 255 is now preferred over 245s.

 

Yeah, I guess I should've searched first.

Someone said I should have "pulled codes" to get the right size. What does that mean?

 

Listen to trav

 

Okie doke. I’ve only been here 8, 9 years.

Sooooooo…. What?

 

You got it right, after doing some research I saw that setup used a lot and the availability is a lot better. Thats also the main reason I went with the Firehawk, I was originally going for the Potenza sport (I am actually running Potenza S-04 and love them) but couldn't find them in stock for a few more months. Great reviews on the Firehawk specially for the price.

 

just going to throw this out there... i had the michelin ps3's on my c6z, and michelin ps4's on this vette.... i wouldnt put another tire on my car

my ats-v i had the continental extreme contact.... hated them. on my 350z, the last tires i put on there were the bfg sport comp2's and even though the same sizes as before (hankook v12) the bfg were noticably wider

 

Nice chart, not that it's wrong but IMO you should pick your tire sizes and then order wheels to fit. That's how I did it with my Z, I knew I wanted 275/305 and the manufacturer measured width for those is 9.5/11.
After that I figured out offsets, for a 245/275 I'd go 8.5/9.5 or 9/10, no need to pay for extra wheel or have extra weight without use.
I also agree with Trav on tires...and here are pics to explain why.



Notice how much wider the PS4S are to the DWS06 lol?

 

Mind you those are the same size tire and are meant for a 8.5 and my wheels are 8 wide.
Side note, it is crazy how much stuff has changed with wheel diameters. 17s and 18s were uncommon premium sizes not to long ago and now 18s are the bottom of the barrel, and 19/20 the premium options.

 

I only use the chart to figure out tire diameters for all my cars (but threw in the range of sizes once I got started and couldn't stop). Width is width (with variances between makes and models of course) and yes, measured widths vary quite a bit but as long as we're in the ballpark and it works, no mattuh.

I haven 't swapped out my wheels for over 2 years (when it used to be every two months). Lazy... gotta move the cars out of the garage now rather than just pulling in my Z. Two much automotive Tetris.

 

Asuka CF Hood USDM Nismo V1 side skirts USDM Front hood weather seal USDM 05 Front bumper Clear bumper reflector Z1 motorsport black powder coated engine undershroud (box) SPL front lower control arm bushing (small box)

 

So after putting the Z on the lift several times and having to drive on some DIY ramp extenders that I made years ago in order to get enough clearance for the lift arms thanks to my chargespeed bottomline side skirts, I got these...




First world problems, I know

 

^^^ That floor is STILL spotless!!!

 

I bought a pair of low "plastic" ramps for jack clearance at one point years ago. Horrible, they slid so badly on standard concrete floor that I couldn't even get the car on them so I returned 'em. Ordered a set of 4" Race Ramps. Haven't looked back. Jack slides right in and done!

 

The epoxy coating is good stuff. There are a few scratches and mars here and there, but for the most part, I'm pretty pleased with the durability! I've done about half a dozen oil changes, brake replacement, and some suspension and exhaust stuff. I bought a commercial mop and rolling bucket and try to clean up after doing things with some neutral pH cleaner. Very reminiscent of my days in high school cleaning up the kitchen after close.

Hey Mic! I'm a big fan of race ramps, but I couldn't find any two-piece detachable ramps that weren't obscenely long. I saw the 4" and 5" H Hook 8 degree ramps (34" and 48", respectively), but the incline portion did not detach allowing the lift arm to slide to the jack point. I saw the 2-piece multi-purpose combo ramps that detach, but those things are freaking 80" long!

I was thinking about getting the 11.9 degree 4" roll-up ramps or the 7.8 degree 3" Trak-Jax ramps, but they're not detachable and the lift arm might or might not clear the ramps to get into position.

Do you remember which model you have? I haven't tried the Cusco ramps yet, and I hope they don't slide all over the place with the anti-slip additive in the epoxy, but if so, I might pull the trigger on the Trak-Jax.

 

Don't recall model and there's two cars blocking the garage right now. Will look at them tomorrow. But from memory, they are 4" at the highest point, only about 36-48" long and have a wheel stop moulded in at the end but no trough (depression) at the top for long term storage.

EDIT: OK Daniel, decided to go move all the cars and such just for you! (And my I-need-to-know/OCD was bothering me. ) And I think its going to keep bothering me because I do not see these on the Race Ramps site! Near as I can tell, they are most similar to these but shorter.



I was wrong: Note the 12" rule on top. Full length is only 30". So I don't know what model they are. Don't think they're copies, I seem to recall buying them direct. But whatever, they do the job, almost as well as the homemade roll up stands my dad built from yesteryear.

 

Thanks Mic! Maybe you have a discontinued model, but they look very similar to the 3" Track-Jax Ramps with the stop.



Thanks for playing musical cars!

EDIT: Upon further inspection, I'm about 99% sure you have those with them being 30" in length. Race Ramps FTW!

 

Yup, that's gotta be them. And yes, they're only 3" tall.

No matter what they are, they work. No more bangin' the jack on the front bumper or on the x-member.